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... Elshaarani et al. [9] used JSCP as filler for medium-density polyethylene (MDPE) and found that incorporation of JSCP into the MDPE matrix reduced tensile, flexural and impact strengths of the latter; but, the tensile and flexural moduli of MDPE were enhanced compared with that of the control. Mohan et al. [10] observed that JSCP could be used as filler in a bidirectional fabricreinforced matrix polymer composite. But, JSCP/epoxy composite has not yet been reported in literature. ...
... The correlation between specific wear rate, weight loss due to wear and mechanical properties was reported in literature [10,[18][19][20]. In general, incorporation of filler increases the tensile strength (r) and reduces the elongation (e). ...
... Hence, the product (rÁe) -1 factor may become smaller in the case of a filled composite compared to the neat matrix. Mohan et al. [10] reported that Jatropha oil cake-filled glass/epoxy hybrid composite, which had the lowest specific rate also, had the lowest value for the (rÁe) -1 factor. But, in the present work the lowest specific wear rate was observed for the composite having the highest value of the (rÁe) -1 factor. ...
Article
Jatropha seed cake particulate (JSCP)-reinforced epoxy composites were prepared by open mold resin casting method. The influence of JSCP on mechanical and dry sliding wear properties of epoxy was experimentally investigated as per the ASTM standards. Dry sliding wear test was conducted for these composites at a constant sliding distance of 500 m with different sliding velocities and applied loads by a pin-on-disc wear test machine. The results revealed that incorporation of JSCP decreased the specific wear rate and coefficient of friction while improving the mechanical properties. The composite reinforced with 40 wt% of JSCP exhibited better mechanical properties and wear behavior compared to the neat epoxy and other compositions of JSCP/epoxy composites. The results of this study indicate that jatropha seed cake powder can be used as biosolid lubricant filler for epoxy.
... Mohan et al. 23 prepared oil cake-filled woven fabric GF-reinforced epoxy composites with the individual fiber diameter 18 mm. The magnetic stirrer was used to mix the epoxy resin and hardner with the weight ratio of 100:38. ...
... The tensile test result showed that the stress-strain curve decreases with increase in temperature. Mohan et al. 23 investigated the mechanical properties of jatropha oil cake-filled woven mat E-GFreinforced epoxy composites. The experimental test conducted at longitudinal direction of composite specimen and the surface fracture exposed that the similar breakage of fibers and matrix, which represent good adhesion between fibers and matrix. ...
... Mohan et al. 23 investigated the sliding wear behaviour of Jatropha oil cake-filled woven fabric E-GF-reinforced epoxy composites with different loads (10 and 20 N). The pin on disc setup result showed that the wear loss increased with increase of sliding distance. ...
Article
Full-text available
Glass fibers reinforced polymer composites have been prepared by various manufacturing technology and are widely used for various applications. Initially, ancient Egyptians made containers by glass fibers drawn from heat softened glass. Continues glass fibers were first manufactured in the 1930s for high-temperature electrical application. Nowadays, it has been used in electronics, aviation and automobile application etc. Glass fibers are having excellent properties like high strength, flexibility, stiffness and resistance to chemical harm. It may be in the form of roving’s, chopped strand, yarns, fabrics and mats. Each type of glass fibers have unique properties and are used for various applications in the form of polymer composites. The mechanical, tribological, thermal, water absorption and vibrational properties of various glass fiber reinforced polymer composites were reported.
... Basavarajappa et al.[5,6]showed that incorporation of silicon carbide and graphite to glass/epoxy composites reduced their wear. Mohan et al.[7]incorporated jatropha oil cake to glass/epoxy composites to enhance their wear resistance by reducing their coefficient of friction. Suresha et al.[8]found that wear resistance of glass/epoxy composites was enhanced by Cenospheres obtained from fly ash. ...
... Hence, their product, the (r e) factor, may become smaller in the case of a particulate filled composite compared to the neat matrix. Mohan et al.[7]found that Jatropha oil cake filled glass/epoxy composite had the lowest specific wear rate, which had the lowest (r e) factor. They concluded that the incorporation of Jatropha oil cake to glass/epoxy composite, increased both e and r. ...
Article
Multi-layered laminates of bi-directionally woven E-glass fabric/epoxy with different loading of graphite particles were made by hand layup followed by compression molding. Tensile and flexural behaviors, impact strength, hardness and density of these laminates were determined. Wear behaviors of these composites were investigated by a pin-on-disc wear test apparatus. Specific wear rates of these compos-ites strongly depend on their filler content and applied normal loads. The hybrid composite containing 3 wt% of graphite exhibits the optimum mechanical and wear performances. A further increase in the graphite content increases the specific wear rate and deteriorates the mechanical behavior. The lowest (r e) À1 factor (the reciprocal of the product of tensile strength and elongation at break) signifies the low-est specific wear rate. The results of the morphology study of the wear test specimens support the results of the wear test.
... Recently, relatively new polymerization methods such as acyclic diene metathesis polymerization [147] and ring-opening metathesis polymerization [148,149] of functionalized fatty alcohols have been employed to synthesize vegetable oil-based polymers as well. Polymerization of vegetable oils/derivatives in the presence of different organic or inorganic nanofillers produces polymer nano-composites, which are extensively applied in the automotive industry, especially as an antiwear coating/additive in lubricants [150]. ...
Article
Full-text available
Chemically modifying vegetable oils to produce an alternative to petroleum-based materials is one of the most important emerging industrial research areas today because of the adverse effects of petroleum products on the environment and the shortage of petroleum resources. Biolubricants, bioplasticizers, non-isocyanate polyurethanes, biofuel, coating materials, biocomposites, and other value-added chemicals can easily be produced by chemically modifying vegetable oils. This short review discusses using vegetable oils or their derivatives to prepare lubricants that are environmentally safe. Chemically modified vegetable oils are generally used as base fluids to formulate environmentally friendly lubricants. Reports of their application as sustainable additives have attracted special attention recently because of their enhanced multifunctional performances (single additives perform several functions, i.e., viscosity index improver, pour point depressant, antiwear products) and biodegradability compared with commercial additives. Here, we have reviewed the use of chemically modified vegetable oils as base fluids and additives to prepare a cost-effective and environmentally friendly lubricant composition.
... The wear resistance offered by different composites of the present research investigation shows the following sequence: Ta/NbC -G-E > WC + Ta/NbC -G-E > G-E. At this juncture, the authors are pleased to quote the research work of Bijwe et al. [12,[22][23][24][25][26][27]. Which confirm that addition of 4% of fillers such as Ta/NbC made in their present study also has brought in considerable improvement in abrasion resistance. ...
Article
The effect of incorporation of tungsten carbide (WC) and tantalum niobium carbide (Ta/NbC) powders on three-body abrasive wear behaviour in glass fabric–epoxy (G–E) composites was investigated and findings are analysed. A vacuum assisted resin transfer moulding (VARTM) technique was employed to obtain a series of G–E composites containing different fillers (WC and WC+Ta/NbC). Dry sand rubber wheel abrasion test was carried out at 200rpm speed. The effect of different loads (22 and 32N) and abrading distances (from 135 to 540m) on the performance of the wear resistance were measured. The wear volume loss of the composites was found increasing with the increase in abrading distances and under the same conditions the specific wear rate decreases. The hard powders filled G–E composite systems exhibit lower wear volume loss and lower specific wear rate as compared to unfilled G–E composite system. The features of worn surfaces of the specimen were evaluated at higher and lower abrading distances at load of 32N were using scanning electron microscope (SEM) and results indicate more severe damage to matrix and glass fiber in unfilled composite system as compared to hard powder filled composites.
... In the present work wear studies have been carried out for graphitefilled glass reinforced-epoxy composite and unfilled glassreinforced-epoxy composites at various temperatures such as 30 C, 50 C, 70 C and 90 C and reported. Considerable information=data related to this present work is available in the literature [12][13][14][15][16][17][18][19][20] . ...
Article
Effect of filler material on sliding wear behavior of Glass-Epoxy (G-E) composites has been investigated. The sliding distance, applied load, sliding velocity and temperature are the parameters used for the study. The fabricated wear specimens were tested by using pin-on-disk test rig. The result shows that the wear loss increases with increase in temperature and applied load and under the same conditions the coefficient of friction decreases. However, graphite-filled G-E composite exhibits lower wear rate and lower coefficient of friction as compared to unfilled composite. The features of worn surfaces of the specimens were examined under scanning electron microscope.
... The results revealed that jatropa oil cake -filled composites exhibit better sliding wear performance in all the tested conditions. The SEM results indicate severe damage to matrix and glass fibre in unfilled composite systems compared to jatropa oil cake -filled composite (Mohan et al., 2011). Many researchers (Sari and Sınmazçelik, 2007;Samyn et al., 2005;Bijwe et al., 2000) have reported that the wear behavior of polymer composites improves with the incorporation of solid lubricants. ...
Article
Full-text available
Purpose – The aim of the this study is to develop a new class of composites which would be more commercially viable and environmentally sustainable via reduced resource depletion, as there has been global interest in utilization of natural resources. The dry sliding wear behavior of glass-epoxy (G-E)-based composites filled with tamarind kernel powder (TKP) in different volume fractions of fillers (0 per cent, 3 per cent and 6 per cent) was studied as per standards. Design/methodology/approach – In the present study, the analysis and optimization of the wear process has been studied. The Taguchi approach to experimental design was used to identify the effect of wear parameters such as applied load, sliding velocity and sliding distance. Taguchi tools such as analysis of variance and multiple linear regression models have been used to analyze, obtain the significant parameters and evaluate the optimum combination levels of wear process parameters. The results of Taguchi analysis indicate that sliding distance was found to be the prominent parameter affecting wear volume loss compared to other wear parameters. Findings – The G-E composites with 3 and 6 vol.% of TKP had the lowest wear volume loss. Multiple linear regression models for all the tested composites’ results well match with experimental results. Confirmation tests were conducted to validate the analysis. There was a close relationship between the experimental results and the statistical model. Originality/value – However, to the best of author’s knowledge, these literature reports related to natural organic filler materials are limited to analysis of polymer matrix composite. Further, the addition of TKP particle as a potential filler has not been addressed. An attempt has been made to clarify the technical viability of TKP as a potential filler for G-E composite.
... Also epoxy in moulded or cast form has excellent dimensional stability and low shrinkage (Kalpakjain et al., 2004;Kishore et al., 2005). Mohan et al. (2010) incorporated jatropha oil cake to glass/epoxy composites to enhance their wear resistance by reducing their coefficient of friction. Suresha et al. (2008) found that wear resistance of glass/epoxy composites was enhanced by Cenospheres obtained from fly ash. ...
Article
Polymer matrix composites are a promising candidate in tribological applications due to possibility of tailoring their properties with special fillers. Several methods have been developed to improve their performance. For instance, the introduction of ceramics such (SiC, Al2O3, TiC, etc.) as within the matrix notably increases the friction coefficient and reduces the wear loss. While glass fibers enhance the toughness of the matrix, silicon carbide shows high hardness, thermal stability and low chemical reactivity, leading to superior friction properties. In this work an attempt was made to evaluate the mechanical properties and tribological behaviour of glass fabric reinforced- epoxy (G-E) composites and silicon carbide filled glass fabric reinforced-epoxy (SiC-G-E) composites. The fabricated wear specimens were tested by using pin-on-disk test rig at various temperatures viz., 30, 60, 90 and 120º C at normal applied loads of 10 N and 20 N. Sliding velocity of the disc of 1.5 m/s was maintained and test was continued for each sample up to a sliding distance of 5000 m. The wear loss in both the composites increases with increase in temperature/applied load and under the same conditions the specific wear rate increases. However, silicon carbide particulate filled G-E composite exhibits lower wear rate with higher coefficient of friction as compared to virgin G-E composite. The elemental composition of worn surface of filler filled composites was quantitatively analyzed by using energy dispersive X-ray spectroscopy. The features of worn surfaces of the specimens tested at higher and lower temperatures at applied normal load of 20 N were examined under scanning electron microscope and also micro mechanism of fractured surfaces were examined through SEM and discussed.
... Also epoxy in moulded or cast form has excellent dimensional stability and low shrinkage (Kalpakjain et al., 2004;Kishore et al., 2005). Mohan et al. (2010) incorporated jatropha oil cake to glass/epoxy composites to enhance their wear resistance by reducing their coefficient of friction. Suresha et al. (2008) found that wear resistance of glass/epoxy composites was enhanced by Cenospheres obtained from fly ash. ...
... Epoxy composites with woven fabric are manufactured by hand lay up technique followed by compression moulding with resin and hardener to ratio as 100:12 [6]. Oil cake-filled glass woven fabric epoxy composites are prepared by epoxy, hardener in the weight ratio of 100:38 using hand layup followed by curing at a pressure of 0.0965MPa for 24 hours using H-type press [7]. Woven mat glass fiber epoxy composites with fabrics at various weaving angles are studied and it was found that the energy absorption increases with decrease of weaving angle between interlacing yarns and accordingly [0 o /20 o ] woven composite exhibits better energy absorption than [0 o /90 o ] woven composite when subjected to impact test [8]. ...
Article
Full-text available
An epoxy matrix reinforced with multi-walled carbon nanotubes (MWCNTs) and graphene nano particles (GNPs) is used to fabricate woven glass fabric epoxy composites using Hand Layup and compression moulding technique. Three types of composites are fabricated using 7-mill plain weave glass fabric, +45o/-45o, 0o-90o multi axial glass woven fabrics as reinforcements and epoxy as matrix. Mechanical characterization is performed on the fabricated composites.0o-90o GWFE composites are fabricated with 0.5 wt%, 1.5 wt% MWCNTs, and 0.5 wt%, 1.5 wt% graphene nano particles (GNPs).The results from mechanical and morphological characterization revealed that specimens containing 0.5 wt%, 1.5 wt% MWCNTs, and 0.5wt %, 1.5 wt% graphene nanoparticles (GNPs) are altered when compared to the glass woven fabric epoxy composites without nanoparticles. Glass woven fabric epoxy (GWFE) composites with 1.5 wt% of MWCNT possess the highest hardness of 90.33 which is 6.27% greater when compared to other composites. The tensile strength of composite specimens containing 1.5 wt% graphene nanoparticles (GNPs) increased by 14.5% over glass woven fabric epoxy (GWFE) composites. The mode of fiber failure in tensile fractured surfaces of GWFE composites is apprised through SEM images.
... N. et. al [54] experimentally investigated dry sliding wear behavior and mechanical properties of Jurupa oil cake (JOC) filled glass epoxy composites. They concluded that wear loss increases with an increase in sliding distance and applied load. ...
Article
The sliding wear behavior of fiber reinforced filler filled polymer based composites has been reviewed. An overview of the problem of sliding wear was given with respect to the operating and experimental parameters during sliding with focus on polymer matrix composites. The high strength fiber reinforced filler filled polymer matrix composites are subjected to sliding wear behavior the wear performance of the material"s is more essential before using in different environment. The new aspects in the experimental studies of wear of fiber and matrix in filler filled composite materials were emphasized in this article. Elaborative investigations as proposed to describe the specific wear rate and wear mechanisms and their importance was mentioned. Recent findings on sliding wear response of various filler filled composites at different modes were also presented. References were quoted on how to solve the problems related to the wear resistance and wear mechanism relationships for fibers, polymer and fillers in polymer matrix composites.
... N. et. al [54] experimentally investigated dry sliding wear behavior and mechanical properties of Jurupa oil cake (JOC) filled glass epoxy composites. They concluded that wear loss increases with an increase in sliding distance and applied load. ...
Article
The sliding wear behavior of fiber reinforced filler filled polymer based composites has been reviewed. An overview of the problem of sliding wear was given with respect to the operating and experimental parameters during sliding with focus on polymer matrix composites. The high strength fiber reinforced filler filled polymer matrix composites are subjected to sliding wear behavior the wear performance of the material’s is more essential before using in different environment. The new aspects in the experimental studies of wear of fiber and matrix in filler filled composite materials were emphasized in this article. Elaborative investigations as proposed to describe the specific wear rate and wear mechanisms and their importance was mentioned. Recent findings on sliding wear response of various filler filled composites at different modes were also presented. References were quoted on how to solve the problems related to the wear resistance and wear mechanism relationships for fibers, polymer and fillers in polymer matrix composites.
... At next treatment of Jatropha oil cakes the filler arises which can be used in polymer composites. The example of the effective use can be seen e.g. in research by Shivamurthy [22] and Mohan [23], who proved the effectivity of the filler from oil cake in powder form e.g. improvement of tribological properties. ...
Conference Paper
The subject of the paper is a research on the wear resistance by friction against loosely fixed abrasive particles on a polymer composite material reinforced by waste microparticles from a pressing process of Jatropha curcas L. seeds with concentration from 5 to 20 wt.%. The seed pressing waste was used in form of Whole seeds cake (WSC), Seed shells (SS) and Seed kernels cake (SKC). The waste, which is difficult to further utilize for its inability to use as feed, arises at the pressing process of Jatropha Curcas L. seeds. A matrix of composite materials was epoxy-based. The wear tests were performed by the device Tester T-07 according to GOST 23.208-79. An addition of the filler significantly increased the wear resistance by friction against a rubber wheel with loosely fixed abrasive particles of sand. The wear resistance was increased up of 69% to 82% at tested polymer composite systems against matrix (resin). Composites materials with the filler Whole seeds cake (WSC) achieved the best results.
... At next treatment of Jatropha oil cakes, the filler arises which can be used in polymer composites. The example of the effective use can be seen e.g. in research by Shivamurthy [22] and Mohan [23], who proved the effectivity of the filler from oil cake in powder form e.g. improvement of tribological properties. ...
Article
Full-text available
The subject of the paper is a research on the wear resistance by friction against loosely fixed abrasive particles on a polymer composite material reinforced by waste microparticles from a pressing process of Jatropha curcas L. seeds with concentration from 5 to 20 wt.%. The seed pressing waste was used in form of Whole seeds cake (WSC), Seed shells (SS) and Seed kernels cake (SKC). The waste, which is difficult to further utilize for its inability to use as feed, arises at the pressing process of Jatropha Curcas L. seeds. A matrix of composite materials was epoxy-based. The wear tests were performed by the device Tester T-07 according to GOST 23.208-79. An addition of the filler significantly increased the wear resistance by friction against a rubber wheel with loosely fixed abrasive particles of sand. The wear resistance was increased up of 69% to 82% at tested polymer composite systems against matrix (resin). Composites materials with the filler Whole seeds cake (WSC) achieved the best results.
... Further it is noted from the Fig. 7(f), pongamia oil cake into Neat epoxy reduces the severe wear to mild wear due to tribo-film formed between steel and disc. The oily nature of POC reduces the wear, increases the adhesion between the matrix and fibre [20][21][22][23]. ...
Article
The wear nature of basalt epoxy specimens incorporated with both POC and UHMWPE was studied by using wear test tribometer. The wear rate was calculated with respect to applied load. The test specimens were formulated using VARTM technique. The % of filler material in the specimen was varied from 0 wt% to 6 wt% (POC and UHMWPE). The outstanding wear behavior was recovered with basalt composites with the fillers. The fracture surface of the specimens was examined by using high resolution scanning electron microscope to analyze the wear data. It was observed that addition of fillers is very important when the worn out of the specimen at initial stages. The process of tribo-film, fibre breakages accounts for wear at much later stages.
... The comparative performances of epoxy-E-glass composite with influence of silicon filler were experimentally investigated under varying load, sliding distances and velocities. It revealed significant control factors of silicon par-ticles that influence the wear behavior [8]. In this paper he described about the fabrication of epoxy and polyester resin composites using aluminium oxide, silicon carbide with different proportion of Al 2 O 3 and SiC along with GFRP. ...
Article
Full-text available
The objective of the work is to investigate the wear rate of two different types of specimens 0/90/0/90 and 0/RD/RD/90. The wear analysis experiment was conducted at three types of loading conditions and also under three various time intervals by following Taguchi’s L9 orthogonal array. In the present day, pin-on-disk is mostly used for wear testing. The effect of the laminated 0/90/0/90 and 0/RD/RD/90 on the weight difference behavior was examined by considering the effect of operating parameters like load, time, and surface roughness. This experimental study would help in finding, the wear rate of brake pad materials in the automobile and we compare the wear rate to that of the glass epoxy composite. Thus we can also find weight difference of the specimen with a rectangular cross-section according to wear test weight difference is minimum 0/RD/RD/90. The conformation test results revealed the predicted weight difference with the Taguchi’s L9 orthogonal array was acceptable when compared with the actual experimental results.
Article
Jatropha curcas is oil plant which has been used to obtain biodiesel once produces oil with potential as raw material to this application. Jatropha cake is a waste product of the process of oil extraction from seeds that can be utilized as a fertilizer. The objective of this work was to investigate the potential of Jatropha cake as a fertilizer for the growth of Blc. Amy Wakasugi ‘Yamanashi’ orchid. Sixty seedlings were treated with Jatropha cake, enriched castor cake, calcium nitrate, chemical fertilizer and their mixtures. Chemical analyses were done to verify nitrogen, phosphorus and potassium contents in these fertilizers. The length, the width and the largest part of the aerial unit were measured, and the number of leaves was determined to evaluate the development of the orchids. Compositions (g kg-1) of Jatropha cake and enriched castor cake were, respectively, nitrogen 38.5 ± 0.4 and 29.3 ± 0.7, phosphorus 5.60 ± 0.23 and 36.81 ± 0.43, potassium 25.6 ± 0.8 and 21.0 ± 0.7. Slight differences in the length and width were observed among the orchids subjected to the different treatments over nine months. For the number of leaves, the treatments with Jatropha cake were found to exhibit the highest values over nine months, whereas the measurements of the largest part of the aerial unit revealed that the use of enriched castor cake was slightly better than the use of the other fertilizers. The results indicated that Jatropha cake exhibits potential for application as a fertilizer for this orchid. © 2014 World Food Ltd. and WFL Publishers. All rights reserved.
Article
Natural particles e.g. in a form of wooden powder but also of fruits residues serve for decreasing costs and for an optimization of some mechanical characteristics in the area of composite materials. For this reason, in this study, a first mechanical characterisation (Hardness) and a tribological characterisation of an epoxy matrix filled with secondary commodities coming from the pressing process of Jatropha curcas L. seeds was carried out. Three different materials have been used as reinforcement of the composite material: Whole seeds (SC), Seed shells (S) and Seed kernels (SKC). A ball-on-flat tribometer with reciprocating motion was employed with frequencies of 5Hz and 10Hz. The tribo test was carried out by using an 8 mm diameter steel ball of AISI 420C (X46Cr13) sliding on a flat specimen of the investigated composite materials without presence of lubricant (dry conditions). The flat specimens of the composite material were made with three different reinforcement concentration (10%, 15% and 20%) materials for any part of the JL seeds used (SC, S and SKC). With the purpose to assess the wear mass loss in the tribo-test a gravimetric analysis was accomplished. An electron microscope was used for the evaluation of particle topography in the worn area af the specimen, after tribo-tests, and in interfacial interaction in this area. 3D topography analysis was carried by using a Confocal Microscope in order to obtained qualitative information on the wear process. From a comparison of the tribological response to the various types of reinforcement, it has emerged that the lower coefficients of friction and wear rate are realized with a reinforcement constituted by the core of the seed (SKC). The gravimetric survey conducted revealed a greater resistance to wear in the composites made with the seed core (SKC). In fact, The lowest value, of the wear mass loss, of the whole series of experiments was obteined in the case of specimens with 20% of reinforcement seed core (SKC) and with 10 Hz of reciprocating motion of the ball on the specimen. This value was of 0.07 mg.
Article
Full-text available
The tribological behaviour of glass epoxy polymer composites with SiC and Graphite particles as secondary fillers was studied using a pin-on-disc wear rig under dry sliding conditions. The influence of wear parameters like, applied load, sliding speed, sliding distance and percentage of secondary fillers, on the wear rate were investigated. A plan of experiments, based on the techniques of Taguchi, was performed to acquire data in a controlled way. An orthogonal array and analysis of variance (ANOVA) were employed to investigate the influence of process parameters on the wear of these composites. The results showed that the inclusion of SiC and Graphite as filler materials in glass epoxy composites will increase the wear resistance of the composite greatly.
Article
This book presents the current understanding of the influences of microstructural parameters on wear. The effects of microstructure become more pronounced as the surface contact of two solid bodies becomes closer and these effects can be substantially reduced by oxide layers and lubricant films. The chapters include a general review of microstructure and properties of materials; classification of wear processes, wear mechanisms for grooving wear, sliding wear in metals, polymers, ceramics and composites; and rolling sliding wear and erosive wear of metals. (H.C.B.)
Article
Polymeric materials containing different fillers and/or reinforcements are frequently used for applications in which friction and wear are critical issues. This overview describes how to design high temperature-resistant thermoplastics, e.g., filled with carbon fibers and internal lubricants, for operation under low friction and wear at elevated temperatures as sliding elements in, e.g., textile drying machines. Further information will be given on the systematic development of continuous fiber/polymer composites with high wear resistance, and on attempts for the prediction of their load-bearing capacity using a finite element approach. Finally, the application of such composites in thermoplastic filament-wound journal-bearings is discussed.
Article
CuO, CuS and CuF2 have been used as fillers in polyetheretherketone (PEEK) and the influence of these fillers on the friction, wear and transfer behavior of the PEEK composites has been studied. Sliding tests were conducted with a pin-on-disk machine at 1.0 m s−1 speed and 0.65 MPa nominal contact pressure under ambient conditions. The pins were made of polymer composites with a filler content of 35 vol.%. The composites were prepared by compression molding. The disks were machined from tool steel blocks and hardened. Experimental results showed that all these fillers reduced the wear of PEEK. The coefficients of friction of the CuS-PEEK and CuF2-PEEK composites during steady state wear were slightly higher than that of unfilled PEEK, but the coefficient was much higher in the case of the CuO-PEEK composite. The transfer films were studied by optical and scanning electron microscopy and their bonding to the counterface by X-ray photoelectron spectroscopy. It has been argued that the ability of these fillers to reduce wear depends upon their ability to form transfer films of the composites on the counterface which are thin and uniform and are strongly bonded to the substrate.
Article
In this study, the strength and erosive characteristics of CaCO3 filled unsaturated polyester/glass fiber (UPR/GFR) composite are evaluated. Samples of UPR with 40, 50 and 60 wt% content of CaCO3 and different CaCO3 par- ticle sizes of 1, 2, 3, 5 and 10 micron were prepared and tested under tensile loading, indentation and erosion conditions. The tensile strength, hardness and erosion wear rate of unsaturated polyester/glass fiber (UPR composite)/CaCO3 compos- ite were obtained and evaluated. The results showed that the higher is the percentage of CaCO3 in the composite and the smaller is the CaCO3 particle size, the higher is the strength and the erosive resistance of the glass fiber reinforced/unsatu- rated polyester composite (UPR-GFR). Furthermore, the highest erosion wear rate is at 90° impingement angle. Finally the results show that the erosive wear of CaCO3 content UPR/GFR composite in a brittle manner.
Article
Mechanical properties and three-body abrasive wear behavior of 5 and 10% w/w bio-based coleus spent (CS) filled and unfilled semi interpenetrating polymer network composites of unsaturated polyester/polymethyl methacrylate (80/20) have been studied. The tensile strength and elongation at break has been evaluated using 4302 Hounsfield Universal testing machine. The effect of abrading distances viz., 150, 300, 450, and 600 m and different loads of 22 and 32 N at 200 rpm on the abrasive wear behavior have been studied using dry sand/rubber wheel abrasive test rig. The CS filler lowered the mechanical properties and improved abrasion resistance of USP/PMMA SIPN. The tensile strength of the composites lies in the range of 25.0-33.1 MPa. The wear volume loss and specific wear rate as a function of abrading distance and load were determined. The wear volume loss increases with increased abrading distance/load for all composites tested. However, the specific wear rate decreased with an increase in abrading distance/load. CS filled USP/PMMA SIPN composites showed better abrasion wear resistance as compared to unfilled USP/PMMA SIPN. The worn surface features have been examined using scanning electron microscope. Also, the wear volume loss was correlated with the product of tensile strength and elongation at break.
Article
The article presents the results of experimental investigation on three-body abrasive wear behavior of nanoclay-filled EVA/LDPE (NC-EVA/LDPE) composites. NC-EVA/LDPE composites with and without compatibilizer were prepared by Brabender Co-Twin extruder (Make: CMEI, Model: 16CME, SPL) and poly(ethylene-co-glycidyl methacrylate) was used as the compatibilizer. The mechanical properties were evaluated using Universal testing machine. In three-body wear tests, silica sand particles of size 200–250 μm were used as dry and loose abrasives. Three-body abrasive wear studies were carried out using dry sand/rubber wheel abrasion test rig. The effect of abrading distance on the abrasive wear behavior of neat EVA, EVA/LDPE, and NC-EVA/LDPE composites was reported. The results showed that the wear volume loss is increased with increase in abrading distance and the specific wear rate decreased with increase in abrading distance. However, the presence of nanoclay filler in EVA/LDPE composite showed a promising trend. Abrasive wear volume of the composites was correlated with mechanical properties such as hardness, tensile strength, and percentage elongation. However, higher weight percentage of LDPE in EVA increased the wear rate. The results indicate that NC-EVA/LDPE with compatibilizer composite exhibits good abrasive wear resistance compared with NC-EVA/LDPE without compatibilizer. Attempts to explain these differing trends are made in this work by analyzing the features observed on the worn surface samples by employing scanning electron microscopy (SEM). POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers
Article
A series of wood flour (WF) filled epoxy composites consisting of five samples were prepared by varying the concentration of WF in step of 10 wt%. These samples were characterized for its wear behavior in abrasive and sliding wear modes to study the influence of WF. It was observed that specific wear rate (k0) of all the composites decreased with increasing load in sliding wear mode. Specific wear rate was of the order of 10−10 m3/Nm in abrasive wear mode and ∼10−14 m3/Nm in sliding wear mode. Composite containing 40 wt% WF exhibited the lowest specific wear rate in abrasive wear mode. While composite containing 20 wt% WF exhibited lowest specific wear rate in sliding wear mode. This was attributed to the fact that in abrasive wear mode, the wear debris consisting of mainly WF particles was maximum for 10 wt% composite and minimum for 40 wt% composite. In sliding wear mode, the exposed WF particles caused maximum roughening of steel counterface in the case of composite containing higher concentration of WF particles. Hence, they exhibited a higher value of specific wear rate. POLYM. COMPOS., 2008. © 2008 Society of Plastics Engineers
Article
The slide wear characteristics of a glass–epoxy (G–E) composite, filled with either rubber or oxide particles, were studied using a block-on-roller test configuration. Mass loss was determined as a function of sliding distance for sliding velocity between 0.5 and 1.5 m/s at three different loads of 42, 140 and 190 N. The worn surfaces were also examined by scanning electron microscopy (SEM). The study showed differing trends with load for the two types of fillers. At low loads, the oxide-filled had lower wear, while at high loads the rubber-filled composite had lower wear. The work also showed that higher loads and sliding velocities bring about changes in worn surface features such as interface separation, inclined fracture of fibres, loss of matrix as well as the appearance of debris with the two different fillers.
Article
The role of nanoclay on the wear characteristics of nylon 6 nanocomposites processed via different routes is examined in this paper. Pristine clay and organoclay were used in melt-extrusion with the matrix resulting in a largely aggregated and a highly exfoliated morphology, respectively. High exfoliation of pristine clay was also achieved by a water-assist process in melt compounding. Nylon 6/pristine clay composite had the worst wear resistance due to the large aggregated clay particles. For the two nylon 6/exfoliated clay nanocomposites, the one with the organically modified clay outperformed that with the pristine clay exfoliated by water. Detailed study on the wear track and subsurface below of the nylon 6/clay composites using both transmission and scanning electron microscopy provided new insight into the differences in their deformation and damage mechanisms. It was revealed that the interfacial adhesion of clay to matrix, and not the exfoliated morphology of clay, played a critical role in wear. However, exfoliated clay morphology is preferred to aggregate morphology. Hence, the superior wear-performance of nylon 6/organoclay nanocomposite is brought about by a combined effect of fine dispersion of clay platelets in nylon 6, high interfacial interaction between nylon 6 and clay layers, and effective constraint on surrounding nylon 6 material exerted by the clay platelets.
Article
Thermosetting composites have been prepared by the use of a biobased resin and spent germ filler, which is a byproduct from a wet ethanol production plant. Microscale tribological measurements were performed on samples with different concentrations of the filler as well as the crosslinker using a ball-on-flat reciprocating microtribometer. Microscale friction and wear behavior during dry sliding were evaluated using a spherical silicon nitride probe (radius 1.2 mm) and a conical diamond (radius 100 μm, cone angle 90°) probe to impose different contact conditions. Finally, a pin-on-disc tribometer was used to study the macroscale wear properties at high loads against an alumina pin. Scanning electron microscopy (SEM) images of wear tracks on the samples were obtained to elucidate deformation mechanisms. All samples showed evidence of abrasive wear in both micro- and macro-scales. It was found that an increase in the concentration of the filler resulted in higher friction coefficients against Si3N4, while an increase in the concentration of the crosslinker lowered the abrasive wear depth. These results provide some insight into the effectiveness of using biobased spent germ–tung oil polymer composites as potential tribomaterials.
Article
BACKGROUND:Jatropha curcas seeds are highly toxic to livestock. The presence of phorbol esters and antinutrients such as trypsin inhibitor, lectin and phytate and the high level of shells in the seed cake prevent its use in animal diets. Using the principle of isoelectric precipitation, the conditions for preparation of the protein concentrate from oil-containing seed cake and defatted seed cake were optimised and the contents of phorbol esters and antinutrients were determined. RESULTS: The recovery of protein concentrate was highest when the proteins from the seed cakes were solubilised at pH 11 for 1 h at 60 °C and the precipitation of these proteins was done by lowering the pH to 4. Under these conditions, over 53% of the total proteins present in the seed cakes were recovered in the protein concentrates. The protein contents in the protein concentrates obtained from the oil-containing seed cake and defatted seed cake were 760 and 820 g kg−1 respectively. Substantial amounts of phorbol esters were present in the protein concentrates (0.86–1.48 mg g−1). Trypsin inhibitor was present at an approximately tenfold higher level in the protein concentrates than in the seed cakes. Lectin and phytate were also present at high levels, but their levels were lower than in the seed cakes. Tannins were present in negligible amounts. CONCLUSION: To make the protein concentrate from Jatropha seed cake fit for use as an ingredient in livestock feed, phorbol esters must be removed and trypsin inhibitor and lectin inactivated by heat treatment. The adverse effects of phytate could be mitigated by addition of phytase in the diet. Copyright
Article
When polymers slide against metal counterfaces, transfer films are formed. This is also the case when sliding occurs between a polymer and another polymer. In the latter case, the transfer of material has been documented by infrared studies which show that material transfer occurs from a polymer of low cohesive energy density to one of higher cohesive energy density. The transfer film formed on a non-polymer counterface is governed by the counterface material and roughness, and of course the sliding conditions. The growth of transfer film with the number of passes is presented and the effect of counterface roughness is examined. The mechanism of wear is discussed with respect to the transfer film.It is shown that when polymers are modified, such as by the addition of fillers, the transfer film affects the tribological behavior. Some fillers affect the development of transfer film and enhance its adhesion to the counterface. Such fillers reduce the wear rate of polymer, often drastically. On the other hand, there are many fillers which have no such effect on the transfer film and wear in these cases is increased. The results of friction and wear behavior for both types of fillers are discussed in view of the transfer film characteristics. The analyses of transfer films as performed by XPS for a few cases are also presented.
Handbook of fillers for plastics
  • H S Katz
  • J V Mileski
Katz HS, Mileski JV (1987) Handbook of fillers for plastics. Von Nostrand Reinhold, NewYork
Applications of jatropha oil seed crop
  • Satheesh Kumar
  • M N Yaakob
  • Z Abdulla
Satheesh Kumar MN, Yaakob Z, Abdulla RS (2009) Applications of jatropha oil seed crop. Recent Pat Mater Sci 2:131-139