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Titanium Carbide: Synthesis, Properties and Applications
Abstract
Composite materials are known in various forms. The two distinctive constituents of these composite materials are the matrix material and the reinforcement material. A variety of materials are used as reinforcing material in composites titanium carbide (TiC). TiC acquired considerable attention because of its unique properties, which make it very attractive for advanced applications. The current review summarizes various synthesis techniques to produce TiC nanocomposite and highlights the major industrial applications of TiC. It was found that for certain techniques, the TiC powder has been synthesized directly, with different shapes and sizes, within a relatively very short time by eliminating a number of intermediate processes. However, this review deals with the detailed literature survey carried out on the preparation of titanium carbide powder, and also covers analyzes the results from the experiments conducted on the preparation of powder by the works of several researchers. Therefore, in-depth conclusions have been done on the research processes that are being carried out on improving the properties of TiC reinforced composites.
... It is a refractory Group IV interstitial carbide characterized by a cubic closed-packed structure with an FCC symmetry [3]. Its structure provides exceptional properties: very high melting temperature (T m = 3067 • C [3]), fair thermal conductivity [3][4][5], which provides good thermal shock resistance, low density with respect to other carbides, and excellent mechanical properties [4,6], like a very high hardness (28)(29)(30)(31)(32)(33)(34)(35)6]), huge elastic modulus (410-510 GPa [4,6]) and fair fracture toughness (3.3 ± 0.1 MPa • m 0.5 [6]). ...
... It is a refractory Group IV interstitial carbide characterized by a cubic closed-packed structure with an FCC symmetry [3]. Its structure provides exceptional properties: very high melting temperature (T m = 3067 • C [3]), fair thermal conductivity [3][4][5], which provides good thermal shock resistance, low density with respect to other carbides, and excellent mechanical properties [4,6], like a very high hardness (28)(29)(30)(31)(32)(33)(34)(35)6]), huge elastic modulus (410-510 GPa [4,6]) and fair fracture toughness (3.3 ± 0.1 MPa • m 0.5 [6]). ...
... It is a refractory Group IV interstitial carbide characterized by a cubic closed-packed structure with an FCC symmetry [3]. Its structure provides exceptional properties: very high melting temperature (T m = 3067 • C [3]), fair thermal conductivity [3][4][5], which provides good thermal shock resistance, low density with respect to other carbides, and excellent mechanical properties [4,6], like a very high hardness (28)(29)(30)(31)(32)(33)(34)(35)6]), huge elastic modulus (410-510 GPa [4,6]) and fair fracture toughness (3.3 ± 0.1 MPa • m 0.5 [6]). ...
... Hydrogen gas produced of (n, p) reaction [33] will be as high as (n, p) cross-section reaction in nuclides. It is similar to the α-particle that can produce helium gas bubbles [34]. ...
... Tis code was performed in a three-dimensional geometry with a unique and complex design. Using ENDF/B-VII.1 [33] is built up the continuous energy nuclear and atomic data libraries available in regimes 10 −11 MeV to 20 MeV. Te calculation aims to measure neutronic performance and radiation damage, such as tritium breeding, energy multiplication factor, gas production, and displacement per atom for FW materials of the HCLL blanket module. ...
... (n, c) reaction cross section as an absorption reaction in nuclides using ENDF/B-VII.1[33]. (a) (n, p) reaction cross-section and (b) (n, α) reaction cross-section as absorption reaction in nuclides by using ENDF/B-VII.1[33]. ...
Neutronic analysis in the HCLL blanket module has been established, and the calculation was performed by the ITER team, including the first wall (FW). In this study, seven materials have been investigated for FW material by considering characteristics such as high neutron fluence capability, low degradation, under irradiation, and high compatibility for blanket material. A three-dimensional configuration simulated in MCNP5 program codes was performed to investigate the neutronic performance and radiation damage effect. Employing seven candidates are vanadium carbide (VC), titanium carbide (TiC), vanadium alloy (V-5Cr-5Ti), graphite (C), tungsten alloy (W-CuCrZr), ceramic alloy (SiC), and HT-9 to study optimization of FW materials configurated in the HCLL blanket module. This novelty study concludes that vanadium alloy (V-5Cr-5Ti) is becoming a promising material candidate. This alloy has the highest number of neutronic performing for 1.27 TBR and 1.26 in multiplication energy factor in all investigations. Meanwhile, the amount of atomic displacement, hydrogen, and helium production are around 22.31 appm, 765.55 appm, and 281.57 appm, respectively. Even though vanadium alloy has a reasonably high radiation damage effect, it is still tolerable compared to several thresholds of DPA. So, it is considered excellent material for FW. Nevertheless, this alloy can replace after 13.45 years for radiation damage.
... Additionally, distinct reflections corresponding to non-stoichiometric TiC x carbide are observed exclusively in the diffractogram of the carbon-containing alloy. The lattice parameter of this carbide determined with XRD is 0.4310 nm (Table 2), which is close to the value of the lattice parameter of stoichiometric TiC carbide, which is 0.4327 nm [30]. ...
... Additionally, distinct reflections corresponding to non-stoichiometric TiCx carbide are observed exclusively in the diffractogram of the carbon-containing alloy. The lattice parameter of this carbide determined with XRD is 0.4310 nm (Table 2), which is close to the value of the lattice parameter of stoichiometric TiC carbide, which is 0.4327 nm [30]. The presence of carbon, known as an α-phase stabilizer, also increases the final temperature of the α → β phase transformation. ...
This study investigates the characteristics of the Ti-5Al-2.5Sn-0.2C alloy, an alpha titanium alloy containing approximately 0.2 wt% carbon—a concentration significantly exceeding the standard allowable limit of 0.08 wt%. The Ti-5Al-2.5Sn-0.2C alloy was melted in a vacuum induction furnace with a cold copper crucible, processed into bar form through hot rolling, and subsequently annealed under standard conditions. The microstructure and mechanical properties of the Ti-5Al-2.5Sn-0.2C alloy were systematically compared with those of the Ti-5Al-2.5Sn alloy (Grade 6), which possesses a similar chemical composition. The results revealed that the addition of 0.2 wt% carbon significantly influences the alloy’s solidification process, phase transformation temperatures, phase composition, and phase lattice parameters. Moreover, the carbon addition enhances key mechanical properties, including tensile strength, yield strength, hardness, and wear resistance, as well as creep and oxidation resistance. While a slight reduction in plasticity and increase in impact energy were observed, the alloy remained within the permissible range defined by existing standards.
... [28,29], as reported in the literature. Also, as indicated in Table 1, the calculated lattice parameter of Vanadium carbide is 4.18 Å compared to the experimental value of4.16 Å [30,31], and the calculated lattice parameter of Titanium carbide is 4.36 Å compared to its experimental value of 4.32 Å [32][33][34]. Finally, the calculated lattice parameter of Manganese sulfide is 5.07 Å compared to its experimental value of 5.60 Å [35]. The good agreement between the theoretical and experimental values and, also, the small deviation between the experimental and theoretical values show that our approximation to model these structures is reliable. ...
... In the same trend, Lin et al. [37] stated that Vanadium carbide has good metal properties, which is in good agreement with our energy band gap calculation (E g ) of 0.007 eV. Also, Mohsen et al. [32] predicted similar characteristics for Titanium carbide with a zero-band gap energy compared to our computed value of 0.09 eV. This contrasts with Manganese sulfide (MnS), where the experimental value of the energy band gap is 3 eV [35,38] compared with our calculated value of 3.2 eV. ...
This study uses plane wave density functional theory (DFT) to investigate the effect of certain metal carbides (Niobium carbide, Vanadium carbide, Titanium carbide, and Manganese sulfide) on hydrogen embrittlement in pipeline steels. Our results predict that the interaction of hydrogen molecules with these metal carbides occurs in the long range with binding energy varying in the energy window [0.043 eV to 0.70 eV].In addition, our study shows the desorption of H2 molecules from these metal carbides in the chemisorptions. Since atomic state hydrogen interacts with NbC, VC, TiC, and MnS to cause embrittlement, we classified the strength of the hydrogen trapping as TiC + H > VC + H > NbC + H> MnS + H. In addition, our study reveals that the carbon site is a more favorable hydrogen-trapping site than the metal one.
... [20,21] as reported in the literature. Also, as indicated in Table 1, the calculated lattice parameter of vanadium carbide is 4.180 Å compared the experimental value of 4.16Å [22,23], and the calculated lattice parameter of titanium carbide is 4.36Å compared to its experimental value of 4.32 Å [24][25][26]. Finally, the calculated lattice parameter and manganese sulfide is 5.07 Å compared to its experimental value of 5.60 Å [27]. The good agreement between the theoretical and experimental value, and also, the small deviation between the experimental and theoretical values showed that our approximation to model these structures is reliable. ...
... In the same trend, Lin et al. [29] stated that the vanadium carbide has good metal properties, which is in good agreement with our energy band gap calculation ( ) of 0.007eV. Also, Mohsen et.al [24] predicted similar characteristic for titanium carbide for a zero band gap energy compared to our computed value of 0.09eV. In contrast with manganese sulfide (MnS) where the experimental value the energy band gap is 3 eV [27,30] compared to our calculated value of 3.2 eV. ...
The study reports the effect of some metal carbides (niobium carbide, vanadium carbide, titanium carbide, and manganese sulfide) on hydrogen embrittlement in the pipeline industry using plane wave’s density functional theory (DFT). Our results predicted that the interaction of hydrogen molecules with these metals carbide occurs in the long range with binding energy varying in the energy window [0.70eV to 0.043eV]. Also, our study shows the desorption of H2 molecules from these metal carbides in the chemisorptions. Since, hydrogen embrittlement, occurs in the atomic state of hydrogen, therefore our finding in the atomic interaction of hydrogen with NbC, VC, TiC, and MnS showed that the strength of the trapping of the hydrogen atom could be classified as: TiC+H>VC+H>NbC+H> MnS+H. In addition, our study reveals that the carbon site is the most favorable hydrogen trapping site than the metal one. Furthermore, our results demonstrate that increasing the layer can also be an efficient way to enhance the trapping capacity.
... [5] Titanium carbide (TiC) is a ceramic particle with remarkable mechanical properties, including a high hardness of 28-35 GPa, a high tensile strength of 258 MPa, and a high Young's modulus of 410-510 GPa, making it an excellent reinforcement material in AMCs. [6] Al/ TiC AMCs exhibited a specific strength of 0.1186 GPa, which is significantly higher than unreinforced Al alloys. [6,7] Such advantageous properties make TiC-reinforced AMCs suitable for use in various engineering applications, including aerospace, automotive, and biomedical industries. ...
... [6] Al/ TiC AMCs exhibited a specific strength of 0.1186 GPa, which is significantly higher than unreinforced Al alloys. [6,7] Such advantageous properties make TiC-reinforced AMCs suitable for use in various engineering applications, including aerospace, automotive, and biomedical industries. The reinforcement with TiC particles shows its tensile strength and hardness more than that of a standard Al matrix. ...
This study presents an experimental investigation on Al matrix composites (AMCs) reinforced titanium carbide (TiC) nano-particles produced by five accumulative roll bonding cycles and three cryorolling (CR) cycles. The microstructures and mechanical properties of composites were studied. The results exhibited consequentially improved mechanical properties for processed Al/TiC AMCs as the number of rolling cycles increased. The presence of TiC in Al matrix showed the combination of elastic modulus, hardness, yield, and ultimate tensile stress of 84 ± 2GPa, 86 ± 3HV, 240 ± 12MPa, and 308 ± 15MPa, respectively. The dispersion of TiC particles was improved with increasing in the number of rolling cycles, resulting in a decrease in porosity between the matrix and reinforcement. This phenomenon was attributed to the breakup of particle clusters and their subsequent uniform dispersion within the Al matrix under CR. The composite microstructure shows uniform TiC particle distribution and grain refinement in the Al matrix, which all contribute to the enhanced mechanical properties.
... In all samples, the intensity of the [200] plane was determined to be the highest. PANI and NTiC sharp peaks have been notified in all NPTiC nanocomposites because of the strength created through dispersion and particle size mechanisms [49]. PANI crystallinity alterations in all nanocomposites were verified by XRD analysis. ...
... When C atoms have created more vacancy, the defected surface becomes more stable. For that reason, work of interfacial adhesion and separation happens in the NTiC crystal structure [49,53]. Therefore, PANI peaks in the nanocomposites became weakened with the introduction of NTiC. ...
... Titanium carbide (TiC) is one of the most interesting materials studied by scientists and technologists due to the combination of desirable properties, such as high hardness, high melting temperature, and chemical and thermal stability [1][2][3]. In most cases, TiC is used as a coating for materials, with these coatings being characterized by high hardness, wear resistance, and thermal conductivity, which make them suitable for a number of industrial applications [4][5][6]. ...
This work presents results on nanosecond laser ablation of a titanium (Ti) plate immersed in a liquid medium using the fundamental wavelength (1064 nm) of a nanosecond Nd:YAG laser system. The laser radiation was focused on the target surface as scanning was accomplished by an XY translation stage. The laser processing of the Ti targets took place in two organic liquids—liquid paraffin and diesel oil. The morphology of the structured surfaces and the structure and phase composition of the samples were studied; their dependences on the processing parameters are discussed. With both liquid media used, crack formation on the surface of the laser-treated Ti target was observed. Formation of a titanium carbide (TiC) phase was found whose properties could be tuned by varying the laser irradiation parameters. Raman measurements were utilized to analyze the carbon structure formed in the resulting coatings. The results of surface electron microscopy reveal that the thickness of the resulting coatings reached 20 µm. Some of the obtained coatings demonstrated about three times higher hardness compared to the native Ti sample. The technique proposed can be used in surface modification of materials in view of improving their mechanical properties.
... TiC, as a typical transition metal carbide, has attracted considerable attention due to its high melting point, high hardness, relatively low density, excellent chemical stability, and good electrical conductivity. It has been widely applied in many fields, such as cutting tools, aviation, high-temperature heat exchangers and microelectronics [1][2][3][4][5]. Generally, TiC can be used as the reinforcement of metal matrix composites to significantly improve the mechanical properties [6][7][8][9][10][11]. ...
The molten-salt electrolytic method was employed to recycle spent SCR catalyst to prepare TiC compound. A systematic investigation has been carried out through thermodynamic calculation and experimental analysis. The effects of graphite content, cell voltage, electrolyzing temperature, and electrolyzing time on electrolytic products were explored. The results show that a suitable amount of graphite content, high cell voltage, and a high electrolyzing temperature are beneficial to promote the formation of TiC compounds. It has also been found that the electroreduction of spent SCR catalyst/graphite can completely transform it into TiC compound in a relatively short time. The final electrolytic product is confirmed to be a solid solution of (Ti, W, Si, V)C. Meanwhile, the electrolytic process and reaction mechanism were investigated through the analysis of intermediates and the thermodynamic calculation. The electrolytic product has a potential application as reinforcement in metal matrix, which is a high additional-value utilization for spent SCR catalysts.
... Showing specifications of TiC[48]. ...
In the current study, an aluminum alloy A356-based hybrid metal matrix composite with red mud and titanium carbide reinforcements is fabricated using a liquid processing route namely the stir casting method. The machining characteristics along with the suitable electrode material during the electric discharge machining of the fabricated composite are determined. The authors are interested in studying the effects of various electric discharge machining (EDM) input parameters like peak current, the voltage on time, and gap voltage affecting the material removal rate (MRR) and tool wear rate (TWR) at the time of machining. Levels of input parameters to conduct the experiments are considered from the literature review, machine capacity, and pilot experiments. To predict the suitable electrode material for the newly fabricated heterogeneous composite material, different electrode materials namely brass, copper, graphite, and stainless steel are used to perform the experiments. Further, the surface roughness of the machined surface is measured and compared for different electrode materials used in the present work. From the results, it has been observed that copper electrode followed by stainless steel electrode show the least tool wear rate (TWR), while brass exhibited the highest TWR. Stainless steel electrode has shown a 90.73% reduction in TWR when compared with brass which has shown the largest TWR. But the Graphite electrode had shown a 57.19% improvement in MRR when compared with stainless steel which had produced a lower value of MRR.
... [ [50][51][52][53] Titanium carbide (TiC) Density (4.91 g/cm 3 ), electrical resistivity (68 µΩ· cm), Young's modulus (410-510 GPa), flexural strength (24-390 MPa), melting temperature (3067 °C), boiling temperature (4820 °C), and thermal conductivity (21 W/mK). [54] Silicon dioxide or silica (SiO2) Density ( [ [66][67][68] ...
This review article provided a thorough examination of porous ceramic materials, concentrating on production, characteristics, and the involvement of pore-forming agents. The primary objective of this research was to evaluate the effects of various ceramic materials and pore-forming agents on the structure, porosity, and mechanical characteristics of porous ceramics. The study's scope included a thorough investigation of key sources of literature, such as academic publications, review articles, and industry reports, to provide a comprehensive understanding of porous ceramic technology. According to the literature review, the selection of ceramic material and pore-forming agents has a significant influence on the pore size distribution, porosity, and mechanical strength of porous ceramics. Various manufacturing methods, including foaming, sintering, and sol-gel procedures, were explored in terms of their influence on porous ceramic microstructure and characteristics. Furthermore, the study emphasized the need to optimize processing settings and select pore-forming agents to obtain the necessary qualities in porous ceramic materials. Overall, this review is useful for researchers, engineers, and practitioners who desire to learn more about porous ceramic manufacturing, characteristics, and applications.
... В основу модели положены физико-химические свойства всех интерпретированных фазовых составляющих, к которым можно отнести температуры кипения, конденсации и кристаллизации [22; 23], а также функциональные зависимости ΔG(t) в условиях равновесного состояния [24]. Дополнительно были привлечены сведения о смачиваемости тугоплавких соединений [22] расплавом металлического никеля для обоснования металлической оболочки на периферии нанокристаллических тугоплавких частиц. ...
In this paper, we studied the formation of ultrafine and nanocrystalline core–shell structures based on refractory compounds of titanium with nickel during plasma-chemical synthesis of a mechanical mixture of TiC and TiNi in a low-temperature nitrogen plasma. Cooling took place in an intensely swirling nitrogen flow in a quenching chamber. The derived products were separated in a vortex-type cyclone and a bag-type fabric filter. After processing, the products were subjected to encapsulation aimed at reducing the pyrophoricity for long-term storage of the resulting finely dispersed powders under normal conditions. X -ray diffraction and high-resolution transmission electron microscopy were used to study the resulting powder products of plasma-chemical synthesis, and density measurements were conducted. Additionally, to define the average particle size more accurately, the specific surface was measured using the BET method. The instrumental research revealed the presence of ultra- and nanodispersed particles with a core–shell structure in the powder products. These particles included titanium carbide-nitride compounds as a refractory core and metallic nickel as a metallic shell. In addition, the presence of complex titanium-nickel nitride Ti 0.7 Ni 0.3 N was recorded. According to direct measurements, the average particle size of the nanocrystalline fraction is 18.9 ± 0.2 nm. The obtained research results enabled us to develop a chemical model of crystallization of TiC x N y –Ni core–shell structures, which is implemented in a hardening chamber at a crystallization rate of 10 ⁵ °С/s. To fabricate the model, we used the reference data on the boiling and crystallization temperatures of the elements and compounds being a part of highly dispersed compositions and recorded by X -ray diffraction, as well as the Δ G ( t ) dependences for TiC and TiN.
... The powder material used is a Titanium Matrix Composite made from alpha-beta titanium alloy (Ti6Al4V) and titanium carbide (TiC) nanoparticles, produced in a High Energy Ball Milling process. This alloy provides high-quality properties: strength to weight ratio, corrosion resistance, biocompatibility, and low thermal expansion [30], and the TiC ceramic particles apport functionalities as its high melting point, elastic modulus, high hardness, low density, high flexure strength, good thermal conductivity, high resistance to corrosion and oxidation, and high thermal shock resistance [31]. A complete LCA study of the production route for this powder has been studied by Santiago-Herrera et al. [32]. ...
As new technologies emerge is necessary to assess if they can actually contribute to sustainable improvement of industrial processes. Life Cycle Assessment (LCA) is a valuable tool to determine environmental impacts and compare systems. However, this comparison raises challenges when they have different maturity. This paper performs ex-ante LCA of an additive manufacturing (AM) technology, based on a step-wise approach built with parametrized modelling, allowing fair comparison with its conventional counterpart, for the study case of a gearbox component. Results show that AM technology generates higher impacts than conventional manufacturing (CM) casting process, using baseline values. These impacts can be reduced by 94% with best operating performances from literature, with emissions from 4520 to 264 kg CO2 eq./kg piece, and non-significant difference with CM (demonstrated by Monte Carlo sampling). A 58% weight reduction is necessary for the AM process to improves its environmental sustainability. This research provides eco-design recommendations supporting decision making for further development of new technology.
... TiC is an extremely hard ceramic (Mohs hardness scale 9.0-9.5) and has a very high melting point (3260 °C) [24]. However, concerning the processing of Al2O3, TiC CMCs are challenging as they require techniques such as spark plasma sintering (SPS) or hot pressing (HP), which are difficult to implement. ...
Ceramic matrix composites are widely studied in the ballistic sector due to their high hardness, fracture toughness, and improved ballistic performance in multilayer shielding systems. However, the presence of dopants in ceramics can pose challenges during processing and potentially compromise the final properties of the sintered material. This study focused on the ceramic processing of Al2O3-based ceramic matrix composites by adding 4 wt.% Nb2O5 (niobium oxide), 0.5 wt.% LiF (lithium fluoride), and 38.5 wt.% TiC (titanium carbide). The composites were produced using cold uniaxial pressing and conventional sintering at 1400 °C for 3 h. The composites were characterized using Archimedes’ principle and scanning electron microscopy (SEM). The results revealed that the samples to which TiC was added exhibited low initial densities, indicating that the applied pressure of 50 MPa during cold pressing was insufficient to adequately densify the green bodies. Moreover, the presence of TiC led to a significant reduction in densification, making it challenging to apply a conductive coating for SEM analysis. Adjustments to the intensity of the electron beam were necessary to conduct the analysis successfully. Conversely, the samples to which TiC was not added exhibited high density values in the green state and yielded consistent results after sintering in line with previous research, indicating a satisfactory degree of sintering in the absence of TiC. These findings highlight the importance of carefully considering the addition of TiC in ceramic matrix composites during processing, which can have a significant impact on densification and subsequent material properties. The results contribute to the understanding of processing parameters with regard to the production of ceramic composites with desirable characteristics for ballistic applications.
... Due to its exceptional properties, including high hardness, high chemical stability, high melting point, strong resistance to abrasion, etc., titanium carbide (TiC) is a promising material that is frequently used for cutting tools [1]. In addition, TiC is employed in optics, electronics, and other fields. ...
Dense nanostructured carbides existing in ternary system Ti-Cr-C were elaborated thanks to a two-steps method. In the first step, nanostructured Ti0.9Cr0.1C carbides were prepared by high-energy planetary ball milling under various times (5, 10, and 20 h), starting from an elemental powder mixture of titanium, chromium, and graphite. In the second step, these nanostructured powders were used to produce densified carbides thanks to the spark plasma sintering (SPS) process under a pressure of 80 MPa. The temperature was fixed at 1800 °C and the holding time was fixed at 5 min. Microstructural characteristics of the samples were investigated using X-ray diffraction (XRD). Scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectroscopy (EDX) was used to investigate the morphology and elemental composition of the samples obtained using SPS. The novelty of this work is to understand the effect of SPS on the microstructural and electrochemical properties of the nanostructured Ti0.9Cr0.1C carbides. The XRD results showed that, during sintering process, the (Ti,Cr)C carbide was decomposed into TiC, Cr7C3, and Cr3C2 phases. An amount of iron was detected as contamination during milling, especially in the case of a sample obtained from 20 h milled carbide. The bulk obtained from the milled powders for 5 and 20 h present similar relative densities of 98.43 and 98.51%, respectively. However, the 5 h milled sample shows slightly higher hardness (93.3 HRA compared to 91.5 HRA) because of the more homogeneous distribution of the (Ti,Cr)C phases and the low iron amount. According to the 0.0011 mm/year corrosion rate and 371.68 kΩ.cm2 charge transfer resistance obtained from the potentiodynamic polarization and EIS tests, the 20 h carbide was the specimen with the highest corrosion resistance.
... V), the focus of this study and which is the most widely used titanium alloy [44], has good characteristics such as a high strength to weight ratio, corrosion resistance, biocompatibility, and low thermal expansion [45]. Additionally, the use of TiC ceramic particles as a reinforcement phase is interesting due to their high melting point, elastic modulus, high hardness, low density, high flexure strength, good thermal conductivity, high resistance to corrosion and oxidation, and high thermal shock resistance [46]. These improved characteristics have been recently demonstrated by several different works, where the combination with ceramic particles increases the wear resistance, corrosion, and strength of the fabricated part [47][48][49][50]. ...
Environmental awareness and the necessary reduction in costs in industrial processes has facilitated the development of novel techniques such as Additive Manufacturing, decreasing the amount of raw materials and energy needed. The longing for improved materials with different and enhanced properties has resulted in research efforts in the Metal Matrix Composites field. These two novelties combined minimise environmental impacts and costs without compromising technical properties. Two technologies can feed Additive Manufacturing techniques with metallic powder: Gas Atomization and High Energy Ball Milling. This study provides a comparative Life Cycle Assessment of these technologies to produce one kilogram of metallic powder for the Directed Energy Deposition technique: a Ti6Al4V alloy, and a Ti6Al4V-TiC Metal–Matrix Composite, respectively. The LCA methodology is according to ISO 14040:2006, and large amounts of information on the use of raw materials, energy consumption, and environmental impacts is provided. Different impact categories following the Environmental Footprint methodology were analysed, showing a big difference between both technologies, with an 87.8% reduction of kg CO2 eq. emitted by High Energy Ball Milling in comparison with Gas Atomization. In addition, an economic analysis was performed, addressing the viability perspective and decision making and showing a 17.2% cost reduction in the conventional process.
... The layered structure of crystals is the important feature of titanium carbide, with a NaCl-type structure [1]. Densely packed metal and carbon atoms are interlaced in planes parallel to the (111) plane. ...
... List of some mechanical properties of the MAX phase materials and TiC[33,72]. ...
... It is from the transition metal series having a rock-salt crystal structure that has drawn in extensive considerations as a material for extreme environments due to its very high melting temperature, high hardness, and good thermal and electrical conductivities (Huber et al. 2003;Tjong and Ma 2011). This material is also widely used for the production of cutting tools, heat-resistant hard alloys, and abrasive and anti-wear materials Hedaiatmofidi et al. 2014;Mhadhbi 2020). TiC has high mechanical resistance, minimal fission products, and small neutron capture cross sections (Rasaki et al. 2018) and is therefore considered to be a promising candidate for reactor material (IAEA 2010) as well as first wall material for thermonuclear reactors and for components in nuclear technology (Wirth et al. 2011). ...
In recent years, the demand for plastic and polymeric materials has been increasing, and it is an inevitable fact that it is an important sector to be considered in terms of sustainability. Both the producer and the consumer consider plastic and polymeric composites as clean and environmentally friendly engineered materials. In the last two decades, scientists have revealed that there has been an increasing interest in using environmentally friendly natural resources to develop polymer materials with synthetic substitute material properties and optimum performance, with the growing concern of the negative environmental effects of artificial materials. Bio-based materials are an indispensable reality for a future sustainable society. The fact that there are about three trillion trees on earth is the fact that wood is one of the most abundant renewable/sustainable materials. Living trees are a biological material with a longer service life by storing carbon dioxide using solar energy, as it is of biodegradable origin. For this reason, it is considered as an important building material for sustainable development. Nanotechnology is a new field that finds its place in almost every industry. Wood nanotechnology is a sector that can both use abundant resources in nature and allow the production of cutting-edge materials with improved mechanical performance. The modification of wood with nanotechnology is based on the principles of green chemistry and on the use of bio-based polymers and nanoparticle technology as well, which leads to a reduction in the overall environmental impact. In addition, it is an inevitable fact that successful wood nanotechnology depends on nanoscience to improve its processing and structural properties. This chapter tries to review potential application of nanomaterials in wood-plastic composites and to introduce their useful aspects in terms of the improved properties.KeywordsGreen materialsLignocellulosic materialsNanomaterialsSustainabilityWood plastic composite (WPC)
... TiC ceramic particles are frequently used as a reinforcement elements in Al-based MMCs due to their superior properties such as high elastic modulus, high hardness and good wettability [107]. The basic physical properties of TiC are listed in Table 4 [108]. Studies show that TiC particles are mostly nanosized, because the refined reinforcing particles effectively improve the mechanical properties of the composite [109,110]. ...
Laser powder bed fusion (LPBF) is one of the most widely used additive manufacturing methods for fabricating metal components. It is possible to produce multi-material structures and functionally graded materials with LPBF. The usability of powder mixtures provides a great potential for the production of metal matrix composites (MMCs) with advanced mechanical properties. Among the wide variety of MMCs, aluminum matrix composites are highly potential candidates for aerospace, automotive and biomedical applications due to their outstanding properties including high wear resistance, better chemical inertness and excellent mechanical properties at elevated temperature. Therefore, in this study, ceramic particle-reinforced Al-based MMCs produced by LPBF method are reviewed for the recent developments. Feedstock preparation methods for MMCs are emphasized. The effects of reinforcement particle properties and LPBF process parameters on the microstructure, densification behavior, hardness and tensile properties are discussed comprehensively. The strengthening mechanisms that occur with the addition of ceramic reinforcement are examined. Summary of the findings from this review and trends for future research in the development of Al-based MMCs by LPBF are addressed in the final section.
... Keywords: oxycarbide, charcoal, titanium dioxide, arc discharge, биомасса Тугоплавкие керамические материалы на основе соединений переходных металлов (нитриды, бориды, карбиды), чьи температуры плавления превышают 2200°C, могут быть применимы в аэрокосмической отрасли, в технологиях металлургической отрасли и в термоядерной энергетике [1][2][3]. Таким материалом является карбид титана (TiC), он имеет структуру типа NaCl (кубическую гранецентрированную). Карбид титана известен благодаря своим свойствам, таким как высокая температура плавления, относительно низкая плотность, высокая твердость, хорошая износостойкость [4]. Обычно для синтеза карбида титана исполь-зуется технически чистый титан или оксид титана, а также углерод различного происхождения. ...
... TiC nanoparticles are very stable and successfully utilized as a reinforcement agent into composites due to their unique mechanical properties, and high temperature stability [28]. It has been reported that TiC can increase the yield strength of the composite materials via dispersion and grain size mechanisms and also can increase toughness by hampering the crack propagation [29]. Further, it is reported that HAp has poor compressive strength and a low degradation rate as compared to the natural bone and teeth, hence its applications for bone replacement are limited [30]. ...
Pure hydroxyapatite (HAp) was synthesized successfully via a wet chemical precipitation method. To study the influence of TiC (weight % of 5, 10, 15) substitution on the mechanical behavior of pure HAp, its composites with TiC were synthesized using a solid-state reaction method. Herein, detailed investigations of pure HAp and its composites using X-ray powder diffraction (XRD), FTIR spectroscopy, Raman spectroscopy, UV-VIS spectroscopy, SEM followed by EDAX and particle size analysis were carried out. XRD study reveals the phase stability of the prepared HAp and composite samples. However, FTIR and Raman spectroscopic studies revealed the bond formation among the various constituents. Mechanical behavior of HAp, and its composites with TiC were studied using numerous parameters like density, Young's modulus, fracture toughness, and load absorption capability. Based on these studies, it was revealed that the addition of 5 wt % substitution of TiC sintered at 1200 °C significantly enhanced the mechanical properties of pure HAp. Hence, 5 wt % of TiC composite 95HAp-5TiC showed the best mechanical characteristics such as density (2.3060 g/cm³), Young's modulus (14.53 MPa), fracture toughness (19.82 MPa m1/2), maximum compressive strength (186 MPa) respectively. Cytotoxicity and osteogenic activities of the synthesized pure HAp and its composite, 95HAp-5TiC were performed using osteoblast cells (mouse calvarial) at different concentrations of the samples (0.01 μg, - 100 μg). From the above studies, the cell viability and ALP activities of the composite, 95HAp-5TiC found to be excellent than that of pure HAp. Hence, this composite sample may be utilized for bone implant applications.
Efforts to quantify iron ion concentrations across fields such as environmental, chemical, health, and food sciences have intensified over the past decade, which drives advancements in analytical methods, particularly electrochemical sensors known for their simplicity, portability, and reliability. The development of electrochemical methods using non-mercury electrodes is increasing as alternatives to environmentally unsafe mercury-based electrodes. However, detecting iron species such as Fe(II) and Fe(III) remains challenging due to their distinct chemical properties, continuous oxidation-state interconversion, presence of interfering species, and complex behavior in diverse environments and matrixes. Selective trace detection demands careful optimization of electrochemical methods, including proper electrode materials selection, electrode surface modifications, operating conditions, and sample pretreatments. This review critically evaluates advancements over the past decade in mercury-free electrode materials and surface modification strategies for iron detection. Strategies include incorporating a variety of nanomaterials, composites, conducting polymers, membranes, and iron-selective ligands to improve sensitivity, selectivity, and performance. Despite advancements, achieving ultra-low detection limits in real-world samples with minimal interference remains challenging and emphasizes the need for enhanced sample pretreatment. This review identifies challenges, knowledge gaps, and future directions and paves the way for advanced iron electrochemical sensors for environmental monitoring, health diagnostics, and analytical precision.
Obtaining electrical power from solar energy through photovoltaic (PV) cell is an excellent alternative to harvesting energy from fossil fuels. However, efficiency is one of the main concerns as the Shockley–Queisser limit puts an upper bound to the efficiency of PV cell. Solar Thermophotovoltaic (STPV) systems are a viable solution to overcome this limit, but they require efficient and meticulous designs of broadband solar absorber and spectrally selective emitter. These designs require high-temperature tolerance, polarization angle and incidence angle insensitivity, and oxidation resistance to endure high-temperature and harsh environmental conditions. This work presents a Titanium carbide-based ultra-broadband absorber and Platinum-based thermal emitter, both of which are reasonable candidates for STPV applications owing to their high melting points. The proposed absorber has a pyramid design as a top nanostructure layer, while the emitter has gratings on its top. The emitter is optimized for lead sulfide (PbS)-based colloidal quantum dot (CQD) PV cell, having a bandgap energy of 0.41 eV, which is an emerging PV cell technology. The proposed absorber exhibits high efficiency of 96%, while the selective emitter achieves PV cell efficiency of 35.2% for PbS based CQD PV cell at the temperature of 1,350 K.
The water gas shift (WGS) reaction is critical for ensuring the purity of hydrogen in industrial hydrogen production. Due to thermodynamic limitations at high temperatures, achieving complete CO conversion at...
We review topological approaches to the analysis of crystal structures of intermetallic compounds and to searching for structural relations between them as the relations between their underlying atomic nets. We introduce the concept of skeletal net to find the simplest system of interatomic contacts in intermetallic compounds, which supports the three-periodic crystal architecture. Using the observed approaches, we have revealed topological relations between crystal structures of binary MeX compounds (Me = Re, Ti or Rh; X = B, C, N, or Si) and found a key role of the body-centered cubic net in their topological hierarchy. We have explored the configuration space of the corresponding crystalline systems by generating all possible ‘subnet-supernet’ topological transformations, optimized the resulting topological motifs with DFT methods and found a new phase of RhB to be stable above 22 GPa. We discuss the role of topological representations in the prediction of new crystalline chemical substances.
We review topological approaches to the analysis of crystal structures of intermetallic compounds and to searching for structural relations between them as the relations between their underlying atomic nets. We introduce the concept of skeletal net to find the simplest system of interatomic contacts in intermetallic compounds, which supports the three-periodic crystal architecture. Using the observed approaches we have revealed topological relations between crystal structures of binary MeX compounds ( Me = Re, Ti or Rh; X = B, C, N or Si) and found a key role of the body-centered cubic net in their topological hierarchy. We have explored the configuration space of the corresponding crystalline systems by generating all possible ‘subnet-supernet’ topological transformations, optimized the resulting topological motifs with DFT methods and found a new phase of RhB to be stable above 22 GPa. We discuss the role of topological representations in the prediction of new crystalline chemical substances.
Wearable technology has emerged as a robust pathway to achieve smart functionalities in healthcare, sports, fitness, and beyond. This study investigates the mechanical and electromechanical properties of silicone rubber (SR) composites. The SR was reinforced with titanium carbide (TiC) and modified with varying (room-temperature vulcanized) RTV-thinner (silicone oil) concentrations. RTV-SR was utilized, which cures at room temperature to form a flexible, durable, and moldable rubber widely used for sealing, bonding, and making molds. The addition of TiC enhanced tensile strength from 0.5 MPa (control) to 0.59 MPa (5 phr of TiC), and tensile modulus from 0.41 MPa to 0.51 MPa. However, the thinner inclusion reduced tensile properties. For instance, the T10 sample (10 phr thinner) showed a tensile strength of 0.51 MPa and a tensile modulus of 0.29 MPa making the composites soft. Thinner addition also increased ductility, with fracture strains rising from 151% (control) to 217% (T10). Compressive strength followed a similar trend, with the control and 5 phr TiC samples exhibiting compressive strengths of 0.18 MPa and 0.17 MPa, respectively, which decreased to 0.12 MPa for the T20 sample. Under cyclic loading, TiC-filled samples showed consistent load patterns, while thinner addition resulted in increased energy dissipation and reduced stiffness. Electromechanical analysis revealed that TiC 5 phr samples exhibited stable piezoelectric responses, with voltage outputs increasing from ±0.1 mV at 15% strain to ±1.0 mV at 40% strain. The T5 samples demonstrated significant voltage improvements, generating ±2.5 mV at 15% strain and ±5 mV at 40% strain. Long-term cyclic tests confirmed the stability of T5 samples, maintaining voltage outputs of -1.5 mV to 1.5 mV over 50 minutes. Response time analysis indicated faster response times for TiC 5 phr samples, decreasing from 145 ms at 15% strain to 102 ms at 40% strain, while thinner addition led to longer response times. Real-time electromechanical tests under mechanical study showed that T5 samples achieved optimal performance with voltage peaks up to ±2.4 mV under thumb pressing. These findings highlight the trade-off between mechanical strength and flexibility, suggesting that an optimal balance of TiC and thinner enhances the properties of silicone rubber composites for applications in wearable technology and sensors.
The Ti-6Al-7 Nb alloy and its carbide possess a wide range of engineering applications, therefore, it is utmost required to fabricate high-quality carburized layers on the alloy surface. In this study, the carburization of Ti-6Al-7 Nb alloy was conducted using molten salts (including Carbon Nano Tubes, LiCl, KCl, and KF) in a planetary ball mill, followed by placement in an alumina tube furnace under a nitrogen atmosphere at 1050 °C for various durations. Several characterization techniques were employed to analyze the results, including X-ray diffraction (XRD), field emission electron microscopy (FE-SEM), X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM). The XRD results reveal that as the carburization duration increased, the alloy achieved complete carburization, forming a 120 µm thick layer of TiC0.3N0.7. After 24 h of carburization, the crystallite size of TiC0.3N0.7 increased, and the micro-strain decreased, indicating improved structural quality. The morphology of the carburized layer at shorter durations exhibits micro-cracks and defects due to incomplete carburization, where carbon (C) and nitrogen (N) could not effectively occupy in the grain boundaries of alloy. After 24 h, an agglomerated, cauliflower-like layer of TiC0.3N0.7 formed, enhancing the alloy's engineering properties. XPS confirmed the presence of carbon and nitrogen in the carburized sample, which contributed to the formation of the TiC0.3N0.7 layer on the alloy surface. AFM analysis supported the SEM findings, revealing broad islands with microgrooves on the carburized layer. These features indicate a thick and well-formed carburized layer, confirming the successful carburization of Ti-6Al-7 Nb. Overall, the study demonstrates that a 24-h carburization process at 1050 °C in molten salts under a nitrogen atmosphere effectively produces a high-quality, thick, and adherent TiC0.3N0.7 layer on Ti-6Al-7 Nb alloy, significantly enhancing its engineering properties.
Hybrid nanofluids (HNFs) have potentials applications in automotive industry, heating and cooling systems, biomedical and other fields due to their ability to introduce higher thermal conductivity than standard nanofluids. The purpose of this study is to investigate and compare the thermal transport performance (in the presence of buoyancy force) of two sets of HNFs. The hybrid nanoparticles which is the combination of titanium carbide and aluminium oxide, and the combination of titanium carbide‐copper oxide are taken into account. Both types of hybrid nanoparticles are dispersed in as a subjective fluid over a vertical nonlinear stretching sheet embedded in a porous medium. This will be the first study on the MXene base material , making it possible for MXene‐based materials to enter the fluid dynamics field. Further, MXene material as heat transporting material is studied less and much more is needed for explore its various aspect. The specific combination of , and is considered because of their promising thermophysical and thermal transport properties. Moreover, considered combination of nanoparticles and the base fluid form a mixture which has thermal relaxation characteristics due to which its deviates from classical Fourier law of heat conduction. Therefore, instead of conventional Fourier's law of heat conduction, the non‐Fourier law of heat conduction is used to formulate the energy equation. It is first time that fhe finite element of method (FEM) is used for such a coupled and nonlinear complex problems of computational fluid dynamics (CFD). The numerical and graphical impacts of magnetic fields, Grashof number, permeable parameter, and thermal relaxation time parameter on velocity, and heat transport are investigated by applying FEM on formulated boundary value problems. In each studied system, increasing the Hartmann number causes an increase the skin friction coefficient and a decrease in the Nusselt number. Moreover, by increasing the thermal relaxation parameter, the temperature of the fluid decreases significantly. The velocity of the modified nanofluids is directly proportional to the Grashof number. The thermal boundary layer thickness (TBLT) and momentum boundary layer thickness (MBLT) of Carreau‐Yasuda (CY)‐HNF (Set II) is greater than CY hybrid nanofluid (CY‐HNF) (Set I) and CY‐Nanofluid (NF), respectively. We believe that the current research work provides new insights to improve the heat transport of nanofluid using appropriate combination of hybrid nanoparticles for practical application.
In this work, titanium carbide nano powders were irradiated at normal conditions of 293.15 K and 1 atm with fluencies of 4.0 × 1012 n/cm2, 8.0 × 1012 n/cm2, 1.3 × 1013 n/cm2, 4.0 × 1014 n/cm2, and 1015 n/cm2 (neutron energy 1 MeV). The microstructure of the titanium carbide nano powders after irradiation was examined using X-ray diffraction, Raman spectroscopy, and FTIR spectroscopic analysis methods. The X-ray diffraction analysis revealed that no significant phase transition or amorphization occurred in the TiC nano powders exposed to fast neutrons. More sensitive results obtained from the FTIR analysis showed that the water molecules absorbed on the material surface were disintegrated under the influence of fast neutrons. Exceptional structural stability to neutron irradiation of titanium carbide without amorphization was also observed by morphological analysis via transmission electron microscopy (TEM) and selected area electron diffraction (SEAD).
This study aims to synthesize TiC + TiB2 reinforced epoxy/glass fiber composites to enhance mechanical properties and resistance to wear and erosion. For this purpose, TiC + TiB2 particles were added to the epoxy matrix in contents of 0, 2.5, 5, 12.5, and 20 wt.%, and the composites were then created through the hand-layout technique. The mechanical, wear, and erosion properties were eventually analyzed. The wear mechanisms of samples were evaluated by scanning electron microscope (SEM) images. The findings indicated that adding 2.5 wt. % of particles maximized the modulus, increasing the tensile and flexural modulus rates by 26 and 17%, respectively. The hardness also improved when TiC + TiB2 particles were added. In fact, it reached the maximum level (58%) once 12.5 wt.% of particles were added. The wear resistance of the composites increased with the TiC + TiB2 content where adding 20 wt.% of the particles enhanced the abrasion resistance by 86% while lowering the friction coefficient. The erosion resistance was analyzed with a rotating device in an abrasive slurry under different variables such as rotation speed, impact angle, and sand rate. The maximum erosion resistance was observed in a composite sample containing 12.5 wt.% of TiC + TiB2 particles.
Green materials can be described as materials developed to minimize human beings’ harmful effects on nature and eliminate many negative situations such as waste and pollution. Green materials have numerous application areas due to their features such as being sustainable, environmentally friendly, low toxicity, lightweight, and low cost. Today, nuclear technology serves society usefully in many fields such as space technology, power generation, medicine, and the food industry. However, effective radiation shielding materials are needed to protect against the harmful effects of radiation. Conventional radiation armor materials used today consist of heavy, inflexible, and toxic materials. It is essential to replace these undesirable properties with environmentally friendly, light, flexible, and non-toxic materials. In this context, one of the usages of green materials is radiation shielding applications. This chapter aims to present an evaluation of studies under different radiation types for radiation shielding applications of green materials. It focuses on recent studies of lead-free and environmentally friendly X-ray, gamma-ray, and neutron shielding materials due to their suitability for use as effective radiation shielding candidates. Additionally, it reviews the use of green materials in electromagnetic interference (EMI) shielding applications.KeywordsElectromagnetic interference (EMI) shieldingEpoxy-based materialsGreen materialsNanocelluloseRadiation shieldingX- and Gamma-raysSustainability
Transition metal-based carbo-nitride solid solution phases have wide application in electrical, electronic, automotive, and refractory industries due to the excellent combination of metallic and ceramic properties. Mainly, carbo-nitride phases were synthesized by high-temperature solid-state diffusion, carbothermal reduction-nitridation, HIP, SHS, pressureless sintering at high temperature, etc. All the methods required considerable investment and production costs, limiting their application in the larger area of research. To overcome all the problems related to the synthesis, one simple, cost-effective, energy-efficient, and environmentally friendly method is required where synthesis will be carried out at a lower temperature with a shorter soaking time. Molten salt-assisted synthesis method fulfils these requirements by accelerating the diffusion rate for phase formation through a chemically inert liquid medium. In this manuscript, carbo-nitride TiC0.5N0.5 and MAX phases Ti2AlC0.5N0.5 and Ti3AlCN have been synthesized using this method with a different atmosphere (Ar, N2, and Air) at a relatively lower temperature with a shorter period of time and characterized by XRD, SEM, particle size analyzer, and HRTEM. The relative density was measured by Archimedes’ principle in case of all the samples and electrical conductivity of the respective samples was determined by the four-probe method.
The radical increase in daily use of metal matrix composites with ceramic reinforcements tangibly increases scrap, which contains valuable ceramic materials. As hard ceramic materials are cost-intensive, there is a significant necessity for their recovery and recycling at all times. This work attempts to recover valuable titanium carbide particles from a scrap of in-situ synthesized AA7075-TiC composites for reuse as reinforcements. The TiC particles were recovered by the corrosive chemical extraction method and analyzed for morphologies, such as shape, phase, and size using scanning electron microscopy, x-ray diffraction, and dynamic light scattering techniques. Further, Al-Mg-Cu-Zn powder was blended with various percentages of the recovered TiC particles to investigate the characteristics of the blends. The compressibility behavior of various blends is correlated with linear and non-linear models, which identified that the Kawakita and modified Cooper-Eaton models showed better fitness in the experimental results, which also explained the mechanisms of compressibility behavior. The extent of the effective percentage addition of recovered TiC as reinforcement in the Al-Mg-Cu-Zn alloy was identified based on the green strength obtained using the diametrical compression test. The best suitable sintering temperature was also determined using thermogravimetric analysis or differential scanning calorimetry and the estimated sinterability index.
Al-based metal matrix composites reinforced with different volume fraction of TiC particles as reinforcement was synthesized by the hot consolidation process. The titanium carbide used in this study was synthesized directly from the titanium ore (ilmenite, FeTiO3) by carbothermic reduction process through thermal plasma technique. The field emission scanning electron micrographs (FESEM) reveals the homogeneous distribution of TiC particles in the Al-matrix. Enhanced Young's modulus and mechanical properties with appreciable ductility were observed in the composite samples. The significant increases in the mechanical properties of the composites demonstrate the effectiveness of the low-density TiC reinforcement.
The paper develops scientific and technological bases for fabrication of titanium carbide which is a nanocomponent of composite materials. The authors determine optimum technology specifications and the main titanium carbide properties: fineness of titaniferous raw materials, carbide-forming agent quantity, set temperature of plasma flow, tempering temperature, titanium carbide yield, productivity, specific surface, size and shape of particles. The paper includes equations to describe how the major specifications of the fabrication technique influence the content of titanium carbide and free carbon in the end product.
A TiC powder is synthesized from a micron-sized mesoporous metatitanic acid-sucrose precursor (precursor M) by a carbothermal reduction process. Control specimens are also prepared using a nanosized TiO
2
-sucrose precursor (precursor T) with a higher cost. When synthesized at 1500°C for 2 h in flowing Ar, the characteristics of the synthesized TiC from precursor M are similar to those of the counterpart from precursor T in terms of the crystal size (58.5 versus 57.4 nm), oxygen content (0.22 wt% versus 0.25 wt%), and representative sizes of mesopores: approximately 2.5 and 19.7–25.0 nm in both specimens. The most salient differences of the two specimens are found in the TiC from precursor M demonstrating (i) a higher crystallinity based on the distinctive doublet peaks in the high-two-theta XRD regime and (ii) a lower specific surface area (79.4 versus 94.8 m
2
/g) with a smaller specific pore volume (0.1 versus 0.2 cm
3
/g) than the counterpart from precursor T.
Investigations have been made on obtaining of nanosized powders of titanium carbide (TiC) by carbothermal reduction of a precursor prepared by sol-gel process. Two methods of precursor gels fabrication of TiC were used: Ti (IV) chloride, ethyleneglycol and citric acid (series A) and Ti (IV) n-propoxide, saccharose and acetic acid (series B). The resulting xerogels are calcined under flowing argon at different temperatures ranging from 800 °C to 1400 °C with holding time from 0.5 h to 10 h. TiC nanopowders were obtained with the specific surface area of 30 m 2 /g – 200 m 2 /g and the size of TiC crystallites of 40 nm – 45 nm. Only the TiC phase has been found by the XRD analysis, but the presence of also some oxygen and free carbon depending on synthesis conditions has been found by chemical analysis. For compacting investigations with spark plasma sintering (SPS) method (1800 °C, heating rate of 100 °C /min and dwelling time of 5 min.) TiC nanopowder (SSA of 88 m 2 /g, containing 72.7 wt. % Ti, 6.6 wt. % O, 20.5 wt. % C total and 7.2 wt. % C free) was used. The sintering begins at 1150 °C, but change of density ends at 1650 °C. The density at this temperature reaches only 89 % of the theoretical and does not rise until 1800 °C. This is probably due to the presence of free carbon in investigated sample, retarding sintering. A significant decrease of admixtures has been observed in ceramic material during sintering.
The preparation of fine TiC powders by carbothermal reduction of TiO2 in vacuum was investigated by XRD, SEM, XRF and laser particle sizer. Thermodynamic analysis indicates that it is easy to prepare TiC in vacuum and the formation sequence of products are Ti4O7 (Magneli phase), Ti3O5, Ti2O3, TiCxO1-x and TiC with the increase of reaction temperature. Experimental results demonstrate that TiC powders with single phase are obtained with molar ratio of TiO2 to C ranging from 1:3.2 to 1:6 at 1 550 °C for 4 h when the system pressure is 50 Pa, and TiC1.0 is gained when the molar ratio of TiO2 to C is 1:4 and 1:5. In addition, fine TiC1.0 powders (D50 equals 3.04 μm) with single phase and low impurities are obtained when the molar ratio of TiO2 to C is 1:4. SEM observation shows that uniform shape, low agglomeration, and loose structure are observed on the surface of block product.
Abstract Conference “Nanotechnology and nanomaterials” (Nano-2013) BUKOVEL, Ukraine, - Lviv, Eurosvit, p.192.
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In the past few years there has been rapid growth in the activities involving particulate materials because of recognized advantages in manufacturing. This growth is attributed to several factors; i) an increased concern over energy utilization, ii) a desire to better control microstructure in engineermg materials, iii) the need for 1mproved material economy, iv) societal and economic pressures for higher productivity and quality, v) requirements for unique property combinations for high performance applica tions, and vi) a desire for net shape forming. Accordingly, liquid phase sintering has received increased attention as part of the growth in particulate materials processing. As a consequence, the commercial applications for liquid phase sintering are expanding rapidly. This active and expanding interest is not well served by available texts. For this reason I felt it was appropriate to write this book on liquid phase sintering. The technology of liquid phase sintering IS quite old and has been in use in the ceramics industry for many centuries. However, the general perception among materials and manufacturing engineers is that liquid phase sintering is still a novel technique. I believe the diverse technological appli cations outlined in this book will dispel I such impressions. Liquid phase. sintering has great value in fabricating several unique materials to near net shapes and will continue to expand in applications as the fundamental attrib utes are better appreciated. I am personally involved with several uses for liquid phase sintering.
This paper reports the preparation of fine titanium carbide (TiC) powder by using titania rich slag as a cheap raw material. The mixture of titania rich slag and activated charcoal was reacted in a thermal plasma reactor for 30. min under argon flowing atmosphere. The reaction product, a fused mass of Fe-TiC composite, was milled to fine powder at ambient atmosphere for 10. h then chemically leached for the removal of iron and other minor impurities. The obtained TiC powder after leaching was characterized by X-ray diffraction (XRD), Raman spectroscopy, electron probe micro analysis (EPMA), field emission scanning electron microscopy (FESEM) and particle size analysis (PSA). XRD, Raman spectroscopy results confirmed the formation of TiC. EPMA, EDS results indicated the synthesized product obtained after leaching to be free from iron and other minor impurities. Particle size analysis result revealed the average particle size of TiC powder to be 2.54. μm.
The fabrication of nanocrystalline TiC by a high-energy ball milling at room temperature was studied. The results show that TiC powder is fabricated within short time. The formation mechanism is self-propagating reactive synthesis induced by mechanical alloying. The particle size of TiC is 5.64 μm, and crystalline grain of TiC is 10 nm. The process of nanocrystalline TiC fabricated is occurred at room temperature.
The TiC powders were synthesized by carbothermal reduction of TiO2 in vacuum using the titania and carbon black as raw materials. The molar ratio of C to TiO2 was 3:1. The crystalline phase, microstructure and morphology of the obtained samples were investigated by XRD and SEM. The results show that single-phase and well-crystallized TiC powders were obtained at 1300°C for 1h when the system pressure was 20 Pa. The particle morphologies are composed of fine grains about 200 nm.
Transition metal carbide precursors have been made in the past by the reaction of alkoxides with polymeric materials to form gels and resins. A new route to transition metal carbide precursors has been developed using alkoxides polymerized with dicarboxylic acids. (Dicarboxylic acid precursors have the advantage of precipitating as powders that can be removed from solvents by filtration and that are not very air sensitive.) Precursors were pyrolyzed under inert or reducing conditions to form metal carbides.
The choice of ligand(s) determined the carbon content after pyrolysis. Unsaturated ligands tended to increase carbon content. Materials from oils to fine powders were produced by varying the stereochemistry of the ligands. The morphology of the pyrolyzed product mimicked that of the precipitated powder. Pyrolysis was typically carried out under Ar/H2 at 1200–1600°C. X-ray diffraction (XRD) was used to follow the incorporation of carbon into the lattice.
The synthesis and characterization of several polymeric titanates and their conversion to carbon deficient TiC is described. The physical properties of one of these titanates allows it to be drawn into fibers and applied to substrates as thin films. Pyrolysis of these fibers and films to carbon deficient TiC is described.
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@inproceedings{OPL:8184387,author = {Ting,S-J. and Chu,C-J. and Limatta,E. and Mackenzie,J. D. and Getman,T. and Hawthorne,M. F.},title = {The Formation of thin Films and Fibers of TiC from a Polymeric Titanate Precursor},booktitle = {Symposium A – Better Ceramics Through Chemistry IV},series = {MRS Proceedings},volume = {180},year = {1990},doi = {10.1557/PROC-180-457},URL = {http://journals.cambridge.org/article_S1946427400559697},}
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The Formation of thin Films and Fibers of TiC from a Polymeric Titanate Precursor
S-J. Ting,C-J. Chu,E. Limatta,J. D. Mackenzie,T. Getman and M. F. Hawthorne (1990).
MRS Proceedings , Volume 180 , 1990, 457
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The Formation of thin Films and Fibers of TiC from a Polymeric Titanate Precursor
S-J. Ting,
C-J. Chu,
E. Limatta,
J. D. Mackenzie,
T. Getman
and M. F. Hawthorne 1990
MRS Proceedings,
,Volume180,
1990,
457
http://journals.cambridge.org/abstract_S1946427400559697
S-J. Ting,
C-J. Chu,
E. Limatta,
J. D. Mackenzie,
T. Getman
and M. F. Hawthorne
(1990).
The Formation of thin Films and Fibers of TiC from a Polymeric Titanate Precursor.
MRS Proceedings,
180,
457
doi:10.1557/PROC-180-457.
0Comments
TiC–ZrC composites were consolidated from TiC and ZrC powders by spark plasma sintering (SPS) at 1500–2200 °C. For sintering temperatures above 1800 °C, the sintered bodies with TiC compositions of 60–90 mol% were densified to relative densities above 95%. For sintering temperatures below 1900 °C, the sintered bodies were composed of Ti- and Zr-rich solid solutions, (Ti, Zr)C; at high temperatures above 2000 °C, they formed a single-phase (Ti, Zr)C. Above 2000 °C, the single-phase (Ti, Zr)C had a uniform morphology. The single-phase (Ti, Zr)C and the composites of Ti- and Zr-rich (Ti, Zr)C for TiC compositions greater than 80 mol% exhibited values of Vickers hardness above 26 GPa.
Titanium carbide (TiC) nanopowders were successfully synthesized by in-situ reduction and carbonization using a precursor comprising elemental titanium, carbon, and cobalt The samples prepared at different conditions were characterized by X-ray diffraction and transmission electron microscopy techniques. The thermolysis process of the precursor was investigated by themogravimetric analysis and differential thermal analysis. The experimental results show that the samples have average sizes ranging within 30-40 nm. In addition, the experimental temperature is 100-900 degrees C lower and the reaction time is 2-90 h shorter than those used in the conventional carbothermal reduction method.
This paper provides an overview of Spark Plasma Sintering (SPS), which is an advanced technology for high-speed sintering of powder materials by applying mechanical pressure to the powder compact and heating it using a pulsed direct current. Some examples of the successful application of the SPS technology in producing materials with high strength characteristics are shown. By optimizing the SPS regimes, the hardness of pure WC ceramics H v ¼ 30C31 GPa (20% higher than that of conventional materials), hardness of pure Al 2 O 3 ceramics H v ¼ 23.5 GPa (50% higher than that of conventional materials) and limit strength of the heavy alloy W–Ni–Fe σ T ¼ 2500 MPa (2 times higher than that of conventional materials) are achievable.
Nano-sized ceramic particle reinforced aluminum matrix composites fabricated using conventional stir casting technique usually present poor distribution of nanoparticles within the matrix and high porosity. In this study, nano-Al2O3/2024 composites were prepared by solid–liquid mixed casting combined with ultrasonic treatment. The obtained composite exhibited fine grain microstructure, reasonable Al2O3 nanoparticles distribution in the matrix, and low porosity. Solid–liquid mixed casting technique was effective in inhibiting the agglomeration of nanoparticles in the matrix. The application of ultrasonic vibration on the composite melt during the solidification not only refined the grain microstructure of the matrix, but also improved the distribution of nano-sized reinforcement. Compared with the matrix, the ultimate tensile strength and yield strength of 1 wt.% nano-Al2O3/2024 composite were enhanced by 37% and 81%, respectively. The better tensile properties were attributed to the uniform distribution of reinforcement and grain refinement of aluminum matrix.
This paper deals with the mechanism and kinetics of titanium carbide formation from titanium dioxide and carbon black. Titanium carbide is one of the key basic materials in modern cutting tools. The influences of titanium dioxide modification and grain size and manufacturing method of the carbon black were investigated by X-ray, thermal, non-metal analyses, but also by scanning electron microscopy and adsorption methods. It was found, that the reduction process proceeds via lower titanium oxides (Magneli phases, various Ti3O5- modifications, Ti2O3) until cubic titanium carboxide is formed. The lattice parameter of formed titanium carboxide is in the range of 0.4295 nm and 0.307 nm. The use of anatase has no accelarating effect on the reaction kinetics, while the grain size of the investigated rutile grades appears to play a role only at higher temperatures. The investigated carbon black grades give no clear picture of the influence of their particle size and the degree of graphitization on the reaction kinetics.
Hydrolysis of the Ti(O-n-Bu)4/furfuryl alcohol mixture resulted in the formation of a polymeric solid. Pyrolysis of the polymer at 1150-degrees-C under argon yielded metallic, gray TiC. When the pyrolysis was carried out in an atmosphere of anhydrous ammonia, pure TiN containing less than 0.8 wt % carbon was obtained at 1000-degrees-C. The structure and pyrolysis chemistry of the precursor were studied by Fourier transform infrared spectroscopy (FT-IR), thermal gravimetric analysis (TGA), gas chromatography (GC), elemental analyses, and X-ray diffraction (XRD).
Field-assisted sintering technology/Spark plasma sintering is a low voltage, direct current (DC) pulsed current activated, pressure-assisted sintering, and synthesis technique, which has been widely applied for materials processing in the recent years. After a description of its working principles and historical background, mechanical, thermal, electrical effects in FAST/SPS are presented along with the role of atmosphere. A selection of successful materials development including refractory materials, nanocrystalline functional ceramics, graded, and non-equilibrium materials is then discussed. Finally, technological aspects (advanced tool concepts, temperature measurement, finite element simulations) are covered.
A new method to synthesize titanium carbide (TiC) from polysiloxanes and titanium (Ti) by employing an in situ reaction is presented. The factors, such as, the annealing temperature and Ti particle size, were found to play a significant effect on the phase composition, structure, thermal behavior, and textural morphology of as-prepared TiC. Moreover, the relative intensity ratio (RIR) method was applied to evaluate the phase purity of TiC. Results demonstrated that the phase purity of the TiC prepared at 1400 °C for 2 h under the argon atmosphere is approximately up to 100 %, confirming the feasibility of the presented new method.
The reaction mechanism of rf reactive sputtering has been investigated by mass spectrometry in an rf diode sputtering system. The sputtering was carried out in the atmosphere of argon-nitrogen, argon-oxygen, and argon-methane mixtures, using a spherical titanium cathode as the target to avoid the edge effect of the planer one. The current of ion species impinging on the substrate was observed as a function of the concentration of the reactive gas. The experimental results show that the reaction process predominantly on the substrate surface rather than both on the target and in the discharge space.
Al 6063 SiCp metal matrix composite (MMC) was drilled by EDM to assess the machinability and obtain an optimal setting of process parameters. The effect of pulse-on (Ton), pulse-off (Toff), pulse current (Ip), gap control setting and flushing pressure on EDM of cast Al 6063-SiCp MMC was investigated. The machining conditions were identified for machining performance of the EDM process with respect to material removal rate (MRR) and tool wear rate (TWR) by pilot experimentation using one-factor-at-a-time approach. Taguchi's technique was further applied to obtain an optimal setting of the EDM process parameters. The experimental results and subsequent analysis revealed that all the selected process parameters were significant. MRR increases with increasing Ip and Ton up to an optimal point and then drops. The effect of Ip is predominant on MRR as compared to other parameters.
The influence of sintering temperature, holding time and pressure condition on densification and mechanical properties of bulk titanium carbide (TiC) fabricated by SPS sintering has been systematically investigated. Experimental data demonstrated that relative density and Vickers hardness (HV) increase with sintering temperature and holding time, but fracture toughness (KIC) was not significantly influenced by sintering parameters. The HV and relative density of samples consolidated by SPS technique at 1600 °C for 5 min under 50 MPa pressure (applied entire sintering cycle) reached 30.31 ± 2.23 GPa and 99.90%, respectively. HV values of ∼24–30 GPa and KIC of ∼3.7–5 MPa m1/2 were obtained in all bulk samples with relative densities of 95.61–99.90% when fabricated under various conditions presented above, without abnormal grain growth. More pronounced effects of pressure condition on grain growth (promoted by grain-boundary diffusion) than on densification were observed. The relationship of fracture toughness and fracture mode is also discussed.
The Bureau of Mines investigated a procedure to produce fine-sized titanium nitride, carbide, and carbonitride powders. These powders, because of their high hardness and abrasion resistance, can be substituted for tungsten carbide in some cutting tool applications. Titanium nitride and carbide powders can be cemented together with nickel. The investigated approach produces titanium nitride by reducing titanium tetrachloride with magnesium or sodium vapor in a nitrogen atmosphere at temperatures between 750 and 1,050°C (1,382 and 1,922°F). Titanium carbide and titanium carbonitride can be formed by adding methane to the nitrogen atmosphere. Titanium tetrachloride reduction efficiencies as high as 98% are achieved. X-ray diffraction analyses showed that the powders contain no major impurities. Because the reactions occur in the gas phase, powders finer than 1 μm are produced.
The TiC and TiB2 powders were successfully synthesized by ball milling the Ti50C50 and Ti33B67 elemental powders, respectively. During ball milling the Ti50C50 powder, a solid solution of C in Ti, Ti(C), was first formed, followed by TiC. After milling for 80 h, the powder was composed of TiC with grain size of 6 nm and a small amount of Ti(C) which was finally completely transformed to TiC after heat treatment. During ball milling the Ti33B67 powder, a solid solution of B in Ti, Ti(B), was first formed followed by the formation of an amorphous structure which transformed into a hexagonal phase of TiB2 with grain size of about 10 nm.
TiC terraces were prepared in situ through self-propagating high-temperature synthesis (SHS) reaction with 10 wt.% FeTiC elemental powder mixtures. The formation and growth mechanism of TiC during the SHS process were explored. The results of combustion wave quenching experiment showed that the formation mechanism of TiC could be ascribed to the dissolution of C into FeTi melt and the precipitation of TiC from the saturated melt. The X-ray diffraction, field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) analyses revealed that TiC terraces grew through the layer-by-layer mechanism along [100] direction, while thin TiC monolayer was formed by two-dimension (2D) nucleation growth mode.
The reduction of TiO2 by graphite or metallic titanium was monitored in an oven for X-rays with a graphite resistance under continuous vacuum. We demonstrate that this brought into play the formation of various oxides, oxycarbides and titanium carbides likely to be formed between 293 and 2300 K, in accordance with a reaction mechanism which we found to take place over four stages. We determined the crystalline characteristics at high temperature for all observed solid phases as well as their composition: TiO2−x, TinO2n−1 with 9≥n≥4,Ti2O3, TiO, Ti2O, TiC1−xOx, TiC. Particular importance is attached to the study of thermal expansion of Magnéli phases which we identified at high temperatures as well as to that of the titanium sesquioxide phase.
Thermal fatigue testing was performed on eight coated or clad materials which have potential application as limiters in pulsed tokamak fusion devices. They are (1) chemically vapor-deposited coatings of TiC, TiB2 and boron on graphite, (2) plasma-sprayed TiB2 on copper, (3) a chemical conversion coating of VB2 on vanadium-clad copper, (4) titanium-clad copper and (5) vanadium-clad copper. Testing consisted of up to 1000 cycles of electron beam heating for 1.5 s at beam power densities of 1 and 2 kW cm−2. Three materials, chemically vapor-deposited TiC and TiB2 on graphite, and plasma-sprayed TiB2 on copper, survived the 1000 cycle 2 kW cm−2 test with slight but acceptable damage. The most notable test failure was VB2 on vanadium-clad copper which deformed severely by a thermal ratcheting mechanism and displayed subsurface melting.
The ultrafine titanium carbonitride particles (TiC0.7N0.3) below 100 nm in mean size were successfully synthesized by Mg-thermal reduction process. The nanostructured sub-stoichimetric titanium carbide (TiC0.7) particles were produced by the magnesium reduction at 1163 K of gaseous TiCl4 + xC(2)Cl(4) and the vacuum heat treatments were performed for five hours to remove residual magnesium and magnesium chloride mixed with TiC0.7. And final TiC0.7N0.3 phase was obtained by nitrification under normal nitrogen gas at 1373 K for 2 h. The high quality of crystal form of TiC0.7N0.3 with the purity above 99.5% and the level near 0.1 mass% oxygen, were produced. We discovered in particular that the temperature lower than 1123 K in vacuum treatment helped to produce the finer and uniform TiCN particles.
Polymeric precursors to a wide range of non-oxide ceramics have been synthesized by reacting metal alkoxides with a range of polyhydric and monohydric alcohols (transesterification). The choice of alcohols controls the form of the polymer and the stoichiometry of the coke produced by charring the polymer in an inert atmosphere. The metal oxide and carbon in the cokes are shown to be very intimately mixed, so that subsequent carbothermal reduction proceeds at reduced temperatures, leading to products of high purity and fine particle size. By incorporating more than one metal in the precursor it is possible to produce ceramic alloys at significantly lower temperatures than conventional means allow.
The mechanical alloying process has been employed successfully for preparing nanocrystalline titanium carbide (TiC) alloy powders. This process was performed in a high-energy ball mill under an argon atmosphere at room temperature. The mechanically reacted powders have been characterized as a function of the milling time by means of X-ray diffraction, scanning electron microscopy and transmission electron microscopy. A single phase of NaCl-type Ti44C56 alloy powders is formed after very short milling time (20 ks). The end product of the milled powders are uniform in size (less than 0.5 μ in diameter) and homogeneous in shape (almost spherical). Moreover, the fabricated Ti44C56 alloy powders have extremely fine cell-like structure, being of about of 3 nm. The presence of free Ti and/or C (reactant materials) in the end product could not be detected. These results demonstrate that the mechanical alloying process can provide a powerful tool for the fabrication of TiC alloy powders at room temperature.
The influence of technological parameters is followed during the carbothermal synthesis of titanium carbide from the dioxide. The carbon grain size, the homogeneity of the carbon/oxide mixtures and the ventilation of the powders' beds are the most important conditions for a rapid reaction. The oxide grain size, the mixing method and the compactness of the mixture has no influence, or very little. These results are explained by the carburizing mechanism where the Boudouard's reaction: C+CO2→2CO plays a central role. This reaction is more rapid when fine carbon is used and when the carbon monoxide is eliminated as soon as formed. These conditions are those required for a complete synthesis of the carbide by: TiO2+3C→TiC+2CO for mixtures having the stoichiometric composition.
X-ray diffraction (XRD) and transmission electron microscopy (TEM) have been used to investigate the fine-scale microstructure of TiN and TiC obtained by chemical vapour deposition (CVD) and a range of proprietary TiN coatings obtained by physical vapour deposition (PVD) (all 2–5 μm thick) deposited on steels by various commercial processes. The major objective has been to examine the variation between, and variability within, apparently similar coatings. TEM involved both plan-view and edge-on specimens. While selected-area diffraction patterns in the transmission electron microscope reflect local variability and some degree of randomness in coating texture, integration over a larger specimen volume by XRD reveals 220∼ and 111∼ preferential orientations in the CVD and PVD samples respectively. XRD further showed that the coatings are sometimes non-stoichiometric while, for some samples, X-ray mapping indicated trans-interfacial diffusion between titanium from the coatings and chromium from the substrate during coating deposition. TEM revealed considerable point-to-point variability in grain structure and grain size within a given sample and from sample to sample with a high degree of in-grain defect (dislocation line and loop) contrast. The results are presented and discussed in terms of the microstructural influence over the subsurface deformation response controlling hardness, friction and wear.
The paper presents a novel process for synthesis of nano-size titanium carbide by reaction between titanium bearing precursor gel and nano carbon particles derived from soot at different temperatures in the range of 1300–1580 °C for 2 h under argon cover. The HRTEM studies of TiC powder synthesized by heating at 1580 °C show the presence of cube shaped particles (~60–140 nm) and hollow rods (diameter~30–185 nm). The average particle size of crystallites, calculated by Scherer equation is observed to be ~35 nm while the surface area–density measurements indicate it to be ~113 nm. The surface area decreases with increase in reaction temperature.
Ultrafine titanium carbide particles were synthesized by liquid-magnesium reduction of vaporized TiCl4+CCl4 solution. Fine TiC particles were produced by the reaction of released Ti and C atoms, and after reduction process vacuum was used to remove the residual phases of MgCl2 and excess Mg. Fixed and free carbon were measured in products synthesized with various parameters as well as stoichiometry and microstructure.
Nanocrystalline TiC is produced by mechanical milling the stoichiometric mixture of α-Ti and graphite powders at room temperature under argon atmosphere within 35min of milling through a self-propagating combustion reaction. Microstructure characterization of the unmilled and ball-milled samples was done by both X-ray diffraction and electron microscopy. It reveals the fact that initially graphite layers were oriented along 〈002〉 and in the course of milling, thin graphite layers were distributed evenly among the grain boundaries of α-Ti particles. Both α-Ti and TiC lattices contain stacking faults of different kinds. The grain size distribution obtained from the Rietveld's method and electron microscopy studies ensure that nanocrystalline TiC particles with almost uniform size (∼13nm) can be prepared by mechanical alloying technique. The result obtained from X-ray analysis corroborates well with the microstructure characterization of nanocrystalline TiC by electron microscopy.
Nanosized titanium carbide particles were synthesized by the reaction of liquid magnesium and vaporized TiCl4+CxCl4 (x=1, 2) solution. Fine titanium carbide particles with about 50nm were successfully produced by combining of Ti and C atoms released by chloride reduction of magnesium, and vacuum was then used to remove the residual phases of MgCl2 and excess Mg. With respect to the reaction kinetic, the activation energy for the reactions of TiCl4+C2Cl4 and Mg was found to 69kJmol−1, which was about half value against the use of TiCl4+CCl4, and such higher reactivity of the former contributed to increase the stoichiometry until the level of TiC0.96 and decrease the free carbon content below 0.3wt.%.
The objective of this paper is to determine the optimal setting of the process parameters on the electro-discharge machining (EDM) machine while machining carbon–carbon composites. The parameters considered are pulse current, gap voltage and pulse-on-time; whereas the responses are electrode wear rate (EWR) and material removal rate (MRR). The optimal setting of the parameters are determined through experiments planned, conducted and analysed using the Taguchi method. It is found that the electrode wear rate reduces substantially, within the region of experimentation, if the parameters are set at their lowest values, while the parameters set at their highest values increase the MRR drastically.
Metal matrix composites (MMCs) have been increasedly used in the industries because of their improved properties over those of non-reinforced alloys. High hardness silicon carbide (SiC) particles are commonly used to reinforce the aluminum alloys, but the full application of such MMCs is however cost sensitive because of the high machining cost. This study investigates the machinability of cast and powder-formed aluminum alloys reinforced with SiC particles. Models for tool wear are validated, while the effect of tool materials, particle distribution, and sub-surface damage are studied and compared.Roughing with uncoated tungsten carbide inserts then finishing with polycrystalline diamond tools is the most economical route to machine SiC reinforced MMCs. The cast MMC exhibits higher machinability than that of the powder-formed MMC mainly because of the favourable shape and distribution of the particles, but weakly because of the fabricating processes. Regardless of the cutting tool materials used for machining, cracked SiC particles and debonded matrix-reinforcement interface were found underneath a machined surface. Such machine-induced defects could be a concern when using the MMCs in a critical application.
Preparation of fine TiC powders by carbothermal reduction of titania/charcoal at vacuum condition was investigated by XRD, SEM, element analysis instrument and Laser Particle Sizer. Experimental results indicate that the formation sequence of products should be Magneli phase (Ti4O7), Ti3O5, Ti2O3, TiCxO1−x and TiC with increasing reaction temperature. The crystal grain grows up and agglomerates gradually in the initial reaction process. Then it diminishes with the liberation of much gas CO. At last, it grows up slightly with the formation of plentiful TiC at higher temperature. Fine TiC powders (D50, 2.05μm) with low impurities were obtained at 1450°C for 8h when the system pressure was about 1–60Pa.
Carbides of Ti have been synthesized directly from industrial ferrotitanium (Fe–Ti) for the first time through high energy mechanical milling and heat treatment. Powders of Fe–Ti mixed with graphite were milled in a planetary ball mill for varying durations between 10 and 40h. The milled mixtures were subsequently heat treated at 1000°C for 15min. The as-milled and heat treated powders were characterized by using SEM-EDX and XRD techniques. With SEM images agglomeration of the particles was noticed with prolonged milling. Formation of carbides of Ti was detected by XRD even in as-milled powders at the early stage of milling. The crystallite size of the carbides gradually decreased with progress in milling. It was demonstrated that nanostructured TiC could be successfully synthesized under suitable processing conditions using industrial grade Fe–Ti as a readily available and cheap raw material.
In this paper, the formation of nanocrystalline TiC from titanium powders and different carbon resources by mechanical alloying (MA) has been investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The experimental results show that nanocrystalline TiC can be synthesized from Ti powders and different carbon resources (activated carbon, carbon fibres or carbon nanotubes) by MA at room temperature. Titanium and different carbon resources have a significant effect on the Ti–C reaction and the formation of TiC during MA. Moreover, the formation of nanocrystalline TiC is governed by a gradual diffusion reaction mechanism during MA, regardless of different carbon resources.