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Investigation on wear properties of super alloys using thermal barrier coating method
Abstract
In the present study super alloys (Alloy 316, Inconel 600 and Titanium-6Al-4 V) are coated with AlCrN and AlTiN of thickness 3 µm and 6 µm using the Physical Vapour Deposition method and its microstructure, wear properties has been characterized. It has been observed that wear resistance property and wear rate of Inconel 600 was lower that the stainless steel 316 and Titanium 6Al 4 V in uncoated condition. It is noted that the optimum condition for minimal wear rate of Inconel material was found when it is coated with Alcona combination with 6 µm layer thickness, load 1 N, speed 250 rpm. On the other hand minimal wear rate of stainless steel 316 was found when it is coated with Alcona combination with 6 µm layer thickness, load 1 N, speed 250 rpm. It is found that after coating the mechanical property (wear resistance) of stainless steel 316 is increased by 15%.
... Additionally, wear-resistant coatings are frequently utilised in internal combustion engines in addition to gas turbines. In addition, thermal barrier coatings, more commonly referred to as TBC, are routinely utilised in these machines [48][49][50]. As a result of the high temperatures at which these parts and components operate, TBCs are utilised in order to extend the amount of time during which they can be utilised. ...
Microwave energy will soon be used in material manufacturing. Microwaves may generate a lot of heat. Through many interactions, microwaves convey electromagnetic energy straight to the material’s molecules. Direct molecular interaction transfers electromagnetic energy to materials. Microwaves are increasingly used to process materials because to their time and energy economy, shorter process cycle times, enhanced mechanical characteristics, and reduced environmental dangers. Microwave processing transfers linearly equal electric and magnetic energy between molecules. Microwaves can process several materials. Metal matrix composites, fibre reinforced polymers (FRP), alloys, ceramics, metals, pulverised metallurgy, metal coatings, and metal cladding are examples. This article lists basic microwave properties and briefly discusses the mechanisms that regulate microwave-material interactions. The essay also discusses the systems that control interactions. Microwave heating basics have been covered here. Cladding, coating, and glazing are the main uses of microwave energy in surface engineering.
The advancement in the alloys led the development of High Entropy Alloys (HEA) that possess improved performance and characteristics. In the current study, AlCoCrFeNi HEA powder was synthesised using gas atomisation and coated onto SS316L stainless steel substrate using the atmospheric plasma spraying process. The microstructural characterisation of the synthesised HEA powder exhibited spherical morphology with a mean particle size of 20 µm. The crystal structure is observed to be BCC phase. The coated samples displayed uniform coating with homogenous distribution of HEA over the coating thickness of 150 µm. The microhardness of the coated samples had an increment of 2.46 times against the uncoated samples due to the excellent bonding and fine dispersion of HEA. The subsequent wear test performed by varying the process parameters revealed improved wear resistance on the coated samples than the uncoated samples. The lower range of load, sliding velocity and sliding distance of coated samples offered 83.92 %, 76.56 % and 74.59 % increments in wear resistance respectively and the characterisation of the worn surface revealed the mechanism to be plastic delamination and adhesive wear. The corrosion test conducted in 3.5 wt% NaCl electrolytic solution also exhibited better corrosion resistance for the coated samples due to the formation of an oxide layer along the coating acting as a protective layer for the enhanced resistance to corrosion.
The present study investigates aluminium alloy powder (Al7075) of mesh size 60 μm and the reinforcement SiC of varying its weight percentage (2 wt%, 4 wt%, 6 wt%) and keeping constant Al2O3 (2 wt%) of particle size <50 nm has been used to synthesis aluminium alloy hybrid nanocomposites. The compaction pressure (350 MPa) and the sintering temperature (750 °C) are used to develop such hybrid composites. The microstructure and mechanical behaviour of progressed composites have been characterized as per ASTM standards. The aluminium alloy hybrid composites sintered effectively and the strengthening particles are consistently disseminated in the matrix alloy without indication of the cluster along with the fine grains of intra dendrite grain boundaries that are precipitated throughout grains of an aluminum matrix. In comparison with base alloy, the hardness (14%) and compressive strength (24%) of synthesized composites have been increased invariably. ASTM B117 salt spray experiment has been performed to study the corrosion properties of incorporated composites. It has been inferred that corrosion-resistant is improved due to the presence of interface AlC2, Al2SiC between the intermixtures. This act as a barrier for disruption and it minimizes the effect of oxidation of developed aluminium hybrid composites.
In this work, aluminium metal matrix composite reinforced with hard silicon nitride (Si3N4) particles have been performed experimentally. Squeeze casting technique was adopted to synthesis the novel AMMC for different weight fractions of Si3N4 (3, 6 and 9%). The AMMC is characterized for their tensile strength, micro-Vickers, density and porosity, compressive strength, impact, corrosion and wear resistance, as per ASTM standards. Observation shows that, with the inclusion of Si3N4 particle, the mechanical behaviour, corrosion and wear-resistant of synthesized composites was considerably improved. Scanning Electron microscope micrograph of worn surfaces displays the presence of grooves parallel to the sliding direction and some plastic deformations. The inclusion of Si3N4 shows deep grooving, that is associated with abrasive wear.
In the present investigation, mechanical, corrosion and fatigue characterization is performed on the fabricated aluminium metal matrix composite (AMMC), by reinforcing nickel (Ni) and copper (Cu) coated 4% carbon fibre (CF) in aluminium alloy (AA6026) matrix. With a view of enhancing the strength of the aluminium alloy, an optimal percentage (4 wt%) of CFs is reinforced; as CFs cannot be directly reinforced in the aluminium matrix due to poor wettability, CFs are coated with Ni and Cu using electroless plating technique for better wettability and bonding between reinforcement and matrix. Properties of the cast alloy and coated CF reinforced composite are compared and the composite with better properties is identified as 4% Cu coated CFs reinforced AMMC. When compared with as-cast alloy and Ni coated CF reinforced composite, the tensile strength of Cu coated CFs composite was higher by 15.36% and 2.55%. Similarly, micro-Vickers hardness was improved by 7.61% and 3.09%, impact strength by 19.61% and 3.39%, flexural strength by 87.50% and 15.38%. The corrosion rate (mils/year) was reduced with incorporation of 4% Cu coated CFs in AA6026 by 59.72% and 23.23% as compared with as-cast and Ni coated CF reinforced composition.
For a varsity of application, materials are demanded with high damping that can lower fundamental natural frequencies, and composites offer widespread options towards designing space structure with lightweight which are controlled effectively. Damping fixtures were made with lightweight composites, for the purpose of transporting aerospace components from one place to another. This present work investigates the damping characteristics of lightweight magnesium-based composite (AZ31+x%Si3N4), subjected to vibration. The composite cantilever beam is excited using an impact hammer and the vibrations generated are recorded using a data acquisition system. The damping properties are related to the density and microstructure of the fabricated composites. Results show that the damping factor changes with higher reinforcement of Si3N4 ceramic particulates and the microstructure obtained during casting have an influence on the damping performance.
In modern day of manufacturing, micromachining plays a key function in machining of new developed harder materials, which is an alternate machining procedure for many processes in industrial scenario. The core objective of this current effort is to progress a micromachining setup and to examine effects of micromachining parameters, for which an open source small Arduino CNC machine was developed for performing the micro-milling operation on a natural fibre (banana) and rice bran particles reinforced polymer matrix composite material with fiber resin combination of 1:3. By using Taguchi method experiments combinations were formulated considering speed, feed and depth of cut and the outputs of MRR and surface roughness were investigated using TOPSIS methodology for identifying the optimal parametric conditions. Analysis of variance is employed for identifying the most significant parameter and a validation experiment was performed with the identified optimum conditions.
In the present study an effort has been made to synthesize B4C and BN reinforced Al7075 hybrid composites using stir casting method by varying its weight percentage (3%, 6% and 9%) of B4C and keeping (3%) of BN constant for marine applications. Morphology of the synthesized aluminum hybrid composite and reinforced particle distribution was studied in detail using optical microscopy. It virtually shows the homogeneous distribution of the reinforcement particles in the base metal matrix and it forms Al3BC, AlB12 and AlN as interfacial reactions. Vickers micro-hardness test has been carried out to evaluate the hardness of hybrid composites. It has been found that with increase in percentage of reinforcement the hardness of the synthesized hybrid composites found to be increased compared with the Al7075 base matrix alloy. Mechanical testing has been carried out on the cast composites specimen of different compositions. It has been inferred that addition of reinforcement B4C and BN to base metal matrix added 22% strength to the hybrid composites. ASTM E9 standard has been used to evaluate the compressive properties of hybrid composites and it has been found that inclusion of harder reinforcement tends to resist the load applied and hence the compression properties of such hybrid composites has been improved. ASTM-B117 has been used to study the corrosion behavior of hybrid composites. The corrosion rate decreased by 18.5% between 3% and 6% boron carbide addition whereas it decreased by 22.4% between 6% and 9% boron carbide addition.
In this work, characterization of Non-Asbestos Organic (NAO) friction composite material was fabricated by reinforcing organic fibers and low metallic friction materials with the sole aim of improving the wear resistance of the composite, that is to be used in brake pad linings. The basic ingredients of the aforementioned composite consist of: rock wool, glass fiber, Aluminium oxide (Al 2 O 3), graphite, copper powder and iron powder with epoxy resin as binder. Graphite and alumina were added as frictional modifier, whereas copper and iron act as metallic filler. Three NAO composites were prepared with different weight proportions of copper and iron powders. Rockwell hardness test, compression strength test and pin-on-disc wear test were done, apart from the micrograph taken using Scanning Electron Microscope (SEM). Results show that, improvement in mechanical and wear properties was achieved with increasing the weight fraction of copper powders, producing lower wear debris due to higher strength and hardness.
Influence of coffee bean natural filler reinforcement (5, 10, 15, 20, 25 and 30% mass fraction) on the mechanical properties of Epoxy LY556 composite, fabricated using compression moulding was analyzed in this work. The maximum mechanical properties were observed for 25% mass fraction of coffee bean natural filler composite. The fracture toughness increases with incorporation of coffee bean filler, due to uniform distribution of coffee bean in epoxy matrix and stress was disseminated equally. It also indicates that bonding between filler and matrix is better and 30% mass fraction filler reveals reduced wettability with the epoxy matrix in composite.
The presence of Hollow particles instead of gas porosity provides a closed cell structure called Syntactic foams. Syntactic foams have gained significant attention in recent years due to their low density, moisture absorption and thermal expansion coefficient compared to other cellular materials, such as open and closed cell structured foams. In terms of mechanical behavior, it is generally more insightful to compare metal matrix syntactic foams with metal foams and metal matrix composites. In comparison with metal foams, they have high compressive yield strength and more homogenous mechanical properties but usually higher densities and lower plasticity. In comparison with metal matrix composites, they have lower strength but offer compressibility, which is not existence in metal matrix composites. Syntactic foams have been extensively studied for aluminum based metal matricesand polymer matrices. Importance in magnesium foams is increasing in recent periods due to their very low density. Only a few studies are available on magnesium matrix syntactic foams processed through powder metallurgy techniques. This review presents an overview of hollow particle filled magnesium matrix (AZ91D/microballons) syntactic foams using powder metallurgy methods.
The utilization of aluminium and its alloys are widely used in many engineering applications because of its good mechanical properties. But it has to be further improved for its tribological properties by adding hard reinforcement like TiC. At the same while, the manufacturing and machining of this hard aluminium metal matrix composite were complex. To overcome this, the modern method like Electrical Discharge Machine (EDM) was used mostly. However, theoretically or experimentally there is not enough data to machine it at optimal parameter. These were made to focus to evaluate and optimize the EDM process parameters for working to Al-TiC using copper hollow tube electrode. To analyze the wear ratio between tool and workpiece, the experiments are done and the results are statistically analyzed during Response Surface Methodology (RSM). The process parameters considered for analysis are Discharge Current, Pulse on Time and Flushing pressure. Finally, the optimum levels of these parameters are determined.
In the present study, an effort has been made to synthesize TiC reinforced magnesium nanocomposites by varying its weight percentage (3%, 6% and 9%) using powder metallurgy for marine applications. The compaction pressure was maintained at 350 MPa for 15 min at 250 °C followed by sintering process. Sintering temperature was maintained at 650 °C in argon protected atmosphere for 8 hrs. Optical microscope and scanning electron microscopy (SEM) have been used to study the microstructure of magnesium nanocomposites. Vickers micro hardness test and ASTM-E9 standards have been used to evaluate the hardness and compressive properties of magnesium nanocomposites. The microstructure of synthesized magnesium nanocomposites revealed that the reinforcement particles are homogeneously distributed in the magnesium matrix without indication of cluster and they appeared as a lamellar precipitates during diffusion. The increase in percentage of reinforcement increases its compressive strength and hardness of magnesium nanocomposites due to the inclusion of stiffer and stronger reinforcement in matrix alloy. B117 salt spray technique was utilized to study the corrosion behavior of magnesium nanocomposites. It has been observed that the corrosion properties of magnesium nanocomposites significantly increased to a maximum of 46% compared with monolithic AZ91D magnesium material.
In the present study, an endeavour has been made to investigate the mechanical properties of hollow glass microspheres reinforced die cast magnesium alloy under vacuum die casting process. The particle size, mass fraction, stirring speed has been considered as input process parameters to analyze the mechanical properties such as hardness, compressive strength, porosity and density of the syntactic foams. Taguchi-Grey relational based multi response optimization has been utilized to compute the optimal process parameters and find the influence of those parameters on performance measures of casting process. From the experimental investigation, the optimal process parameters have been found as particle size (45 microns), mass fraction (20%) and stirring speed (600 rpm) among the chosen process parameters. The highest max–min indicates the particle size has higher influence on determining the mechanical properties of the syntactic foam owing to its importance on determining the porosity. It has been also observed that the density of syntactic foam decreases with increases in the mass percentage of hollow glass microspheres.
In the present scenario, a considerable importance is being given to find newer materials for marine applications. An endeavour has been made to synthesis hollow glass microspheres reinforced magnesium matrix (AZ91D/HGM) syntactic foams and analyze its mechanical properties for such applications in the present study. The 40 μm size reinforcement particles have been added with matrix under dissimilar mass fractions of 15%, 20% and 23% to investigate the interfacial reaction, compressive properties, hardness, density, porosity, corrosion resistance. From the experimental investigation, it has been inferred that the density of foams and corrosion rate have been considerably reduced owing to increase in reinforcement mass fraction. It has also been observed that the developed syntactic foam has produced higher compressive strength due to its cushion effect and higher plateau stress. From the porosity phase analysis, it has been found that the porosity has been increased with increasing mass fraction percentage. From the composition structural analysis, Mg17Al12 has been observed as main interfacial reaction between the microsphere and matrix alloy.
Stemming from the success recorded in the cutting tool industries, the use of physical vapor deposition (PVD) coatings for friction stir welding (FSW) tools is a promising approach to improve their performance and useful lives and hence the economics of the process. In this study, the authors present the results of the first phase of an on-going study to test various metallurgical hard coatings for FSW tools using cathodic arc PVD coating technique for welding structural materials. Aluminum alloy 6061-T6 and alloy steel 4140 grade were chosen as workpiece and FSW tool material, respectively for this preliminary study. The tribological properties of AlCrN coating were evaluated. The tool wear and weld quality resulting from FSW were analyzed and compared for coated and uncoated tools. AlCrN coated sample exhibited improved wear resistance with weight loss of about 87% lesser compared to uncoated sample. FSW performed on 6 mm thick 6061-T6 Al alloy plate showed that AlCrN coated FSW tool produced full penetration weld with no major defects. Also, no delamination of the coating was observed and no trace of the coating was detected in the weld for the FSW paramters employed. Examination of the tools after the FSW showed that the coated tool experienced less reduction in the tool pin dimension as compared to the uncoated tool.
The present work focuses on numerically and experimentally investigating the performance of uncoated, and multi-layer AlTiN coated (coating thickness ranging from 2 to 4 μm) Al2O3-TiCN composite (mixed) ceramic cutting tools while hard turning of AISI 52100 steel (62 HRC). 3D finite element model was developed taking into consideration a hybrid friction criterion to precisely study the behaviour at the sticking and sliding zones of friction numerically. Later, deposition of AlTiN coating was executed on uncoated Al2O3-TiCN inserts using cathodic arc evaporation process. Coating thickness was evaluated from the fractography of coated tools using field emission scanning electron microscopy (FESEM). Turning experiments under dry cutting conditions were performed on a heavy duty lathe machine equipped with a dynamometer using both coated and uncoated cutting tools. Also, wear analysis of the cutting tools was carried out using optical microscopy, scanning electron microscopy (SEM) and FESEM. Comparison of machining responses showed a close agreement between finite element and experimental studies. It was observed from the numerical and experimental results that AlTiN coated tool with 4 μm coating thickness exhibited best machining performance on Al2O3-TiCN inserts during hard turning of AISI 52100 steel.
Wear mode in Inconel alloy-a literature study
- Vaishal