Wear Resistance Of Composites Research Articles

On the impact of using alumina nanoparticles and initial aging on the microstructure and mechanical properties of the AA1050/AA2024 nanostructure composite, created by accumulative roll bonding (ARB) method

In this research, AA1050/AA2024 layered composites were created through six cycles of the ARB process. In this direction, the effect of using the reinforcing nanoparticles and the initial aging process on the mechanical properties and microstructure were researched. Two sheets of AA1050 and one sheet of AA2024 alternatively were used to create the composite. Also, 0.005 vol% Al2O3 nanoparticles were used. Moreover, the aging process lasted for 30 min at 190 ᵒC. Once the aging process was completed, the S′ precipitates with less than 100 nm thickness were formed. After six ARB cycles and using reinforcing particles, the equiaxed ultra-fine grain microstructures were created. The grains were about 500 nm in size. The S′ precipitates improved tensile strength. The alumina nanoparticles resulted in 38% and 32% improvements in the AA1050/AA2024 composite's wear resistance to the annealed AA1050 and AA1050/AA2024 composite sheets, respectively.

Tribological properties of hemp fiber reinforced polylactic acid bio-composites: effect of different types of modification methods

In this study, green composites are prepared with 30 wt.% hemp fibers reinforced polylactic acid (PLA) to enhance the impact and tribological properties. Different surface treatments of alkali and silane, compatibilizer of maleic anhydride (MA), and blends of thermoplastic polyurethane (TPU) and poly (butylene succinate) were applied to improve interfacial adhesion between fibers and matrix. Hemp-reinforced PLA bio-composites were fabricated and characterized by hardness, impact strength, wear, and friction properties. The tribological tests of the injection-molded components were performed under two different loads (10 N and 20 N) as dry-sliding linearly reciprocating motion per ASTM G133. Modified composites gave better tribological properties than unmodified composites. While no remarkable improvement was observed in the hardness value of untreated fiber-reinforced composite, alkali-treated composite reached up to 43% improvement in hardness value. In general, as the load increased, weight loss increase was observed in all composites. Unmodified bio-composite exhibited a very low weight loss and specific wear rate (SWR) compared to neat PLA under 10 N load. The SWR of the MA bio-composite had the lowest value for both loads (10 N and 20 N) compared to the other bio-samples. The TPU blended bio-composite exhibited the highest impact strength (22.96 kJ m−2) after pure PLA (26.5 kJ m−2). Therefore, due to surface treatments and blends applied to the fibers, some composites’ hardness and wear resistance were increased while the impact strength and friction coefficient was decreased. Especially silane surface treatment and MA compatibilizer application increased the wear resistance of composites. When the scanning electron microscope images were examined, it was revealed that the fiber and matrix interface bonding was good, and the fibers were firmly embedded in the matrix. Furthermore, forming a protective thin film layer formed by the polymer debris from the surface during dry-sliding increased the wear performance of the bio-composites.

Tribological properties of UHMWPE/PAANa/Ph4Sn composite materials in seawater lubrication

Abstract The blended composites with ultra-high molecular weight polyethylene (UHMWPE) as the matrix polymer, sodium polyacrylate (PAANa), and tetraphenyltin (Ph4Sn) as fillers were prepared by hot compression molding process. The friction and wear behavior of GCr15 balls with composites mating pairs under the seawater environment was explored, and the friction and wear mechanism was analyzed. The results show that adding PAANa, a polyelectrolyte material, can effectively reduce the friction coefficient of UHMWPE/PAANa/Ph4Sn composites. The wear resistance of composites increased significantly with increasing Ph4Sn content compared with pure UHMWPE, and the best wear resistance was observed at 1% content. The primary wear mechanism of UHMWPE/PAANa/Ph4Sn composites changed from adhesive wear of pure UHMWPE to plastic deformation at lower PAANa and Ph4Sn contents and finally to adhesive wear and spalling. This work provides a theoretical basis for preparing and applying other polymer blend composites.

Study of the influence of reinforcing fillers of different nature on the properties and structure of polytetrafluoroethylene

The paper presents the results of research on the development of polymer composite materials based on polytetrafluoroethylene and basalt or carbon fibers. It has been established that when these fibers are introduced into the polymer, the strength properties of the composites under compression and tension increase in comparison with the initial polymer. As the concentration of fibers in the matrix increases, an increase in the wear resistance of composites up to 41 times is observed observed according to the "finger-disk" friction scheme at a sliding speed of 0.2 m/s and under a load of 160 N. Using scanning electron microscopy, it was found that the structure of the polymer noticeably changes after the addition of fibers of various nature. Photomicrographs of the friction surfaces of composites show that fibers protrude from worn surfaces that protect the polymer from abrasion.

Effect of in-situ (Ti&W)C multiphase particles on three-body abrasive wear of high chromium cast iron

In this paper, the effect of in-situ (Ti&W)C multiphase particles on the microstructure and the three-body abrasive wear behavior of high chromium cast iron was investigated. The results reveal that the different W/Ti ratios in the preforms can lead to significant differences in the microstructure and properties of the composites. The best microstructure and wear resistance of the composite (M3) is achieved when the W/Ti ratio is 4/6. Under the same wear conditions, the wear resistance of the M3 composite is more than twice as high as that of the matrix material. Furthermore, the presence of (Ti&W)C multiphase particles in the microstructure improves the hardness of high chromium cast iron, promoting its transition from cutting, fatigue, and the M7C3 fracture-exfoliation wear mechanism in the abrasive wear to micro-cutting and fatigue wear.

Importance of pin number on mechanical properties and wear performance during manufacturing of AA6061/316 surface composite via FSP

• Manufacturing of AA6061/316 stainless steel composite via FSP technique. • Particle refinement and homogenized dispersion were enhanced by changing the tool from single pin to double pin. • Using a double pin remarkably increased wear resistance of composite. The primary aim of this investigation was to fabricate AA6061/316 surface composites using single and double pin tools through the Friction Stir Processing (FSP) technique. Results depicted that increasing the number of pins from 1 pin to 2 pins remarkably affected the dispersion of reinforcement particles and as a result decreased the size of reinforcement particles from 44.69 to 35.04 µm that can be attributed to the drastic plastic/strain deformation, dynamic recrystallization (DRX), and pinning effect of reinforcement particles.

Tribological performance of AZ91D/HfCp magnesium composite prepared through stir-ultrasonic-squeeze casting technique

The present work investigates the influence of hafnium carbide, an ultra-high temperature ceramic reinforcement on the dry sliding wear behaviour of AZ91D magnesium composite. AZ91D/5 wt.% hafnium carbide composite and AZ91D alloy were fabricated using stir-ultrasonic treatment-squeeze casting method followed by heat treatment (T6). Microstructure and intermetallic phase studies were performed using scanning electron microscopy and X-ray diffraction techniques. Density, porosity and hardness of the materials were determined. Wear tests at room temperature were conducted at various sliding speeds (0.25–1 m/s) and normal loads (12.5–50 N), using a pin-on-disc tribometer. The temperature of wear varied from 50–200 °C for high-temperature wear tests. Compared to alloy, the composite showed better wear performance under all test conditions. Increasing the normal load increased the wear rate of both materials, but the wear rate decreased with an increase in sliding speed. The friction at the sliding interface decreased with an increase in normal load and sliding speed. The mechanisms of wear for both materials were abrasion, delamination, and oxidation at room temperature. At high temperatures, there was a dramatic increase in the wear rate of the alloy at 150 °C, whereas the wear resistance of composites improved up to 150 °C due to the presence of small amounts of hafnium carbide ultra-high temperature ceramic reinforcement. Abrasion, oxidation, delamination, and plastic yield were the primary wear mechanisms at high temperatures.

Evaluation of mechanical and wear properties of AA6063/(Si3N4)6%–12% /(CuN2O6)2%–4% composite via PM route and optimization through robust design technique

The study is to investigate the physical, mechanical, and tribological properties of Al6063 alloy reinforced by Silicon Nitride (Si3N4) & compound Copper Nitrate (CuN2O6) processed via Powder Metallurgy (PM) Techniques. Incorporation of reinforcement in matrix material ranged from 6 to 12% Si3N4 in a 6-step interval, and 2 to 6%CuN2O6 in a two-step interval. The characterizations were made on the PM produced specimens using OM, EDS, XRD and hardness. The reinforcement particles were distributed uniformly is attributed by homogeneous mixer of matrix and reinforcements. The tests were carried out in accordance with ASTM Standards on the Al6063 alloy and its composites. The test findings show that as the reinforcing percentage of ceramic and inorganic compound is increased, properties such as hardness and density rise monolithically and considerably. The dispersion of Si3N4 and CuN2O6 reinforcement in the AA6061 matrix was ensured by x-ray diffraction patterns. In comparison to the base alloy, the hardness of AA6063/12%Si3N4/6% CuN2O6 improved by 88% due to the mismatch of thermal expansion between the Al matrix and reinforcement causes huge internal stress, causing the aluminium matrix to deform plastically to lodge the smaller volume expansion of Si3N4 and CuN2O6 particles. The dry sliding wear test was carried out on a tribometer with a pin-on-disc arrangement, and the findings show that the composite has a higher wear resistance. The Taguchi design of experiments was used to investigate the solution containing parameters employing an orthogonal array, the signal-to-noise ratio, and analysis of variance. The weight percentage of Si3N4/CuN2O6 compound and the relationship between wt% of reinforcement and applied load had the highest impact on composite wear resistance, accounted for 31.66%. Before and after the wear morphology during the wear test, images from a scanning electron microscope and energy dispersive microscopy were used to examine the manufactured composites.

Investigation of mechanical and wear properties of Al6061/Si3N4/MgO hybrid composite fabricated by stir casting method

Among various non-ferrous materials, aluminium and its alloy are considered to be one of the challenging materials having high structural characteristics, superior physical and tribological properties. Nowadays, it has substituted high-density materials in automobile, marine and aerospace applications owing to its high strength to weight ratio. In the field of aluminium matrix composite, most of the research works have been carried out with carbide, alumina and boride as reinforcement. Nitride and Oxide are also suitable materials to be used as reinforcement. The tribological studies of nitride and oxides with different load conditions along with mechanical properties were not fully explored. Therefore, the primary objective of this work is to investigate the mechanical properties and wear rate of hybrid aluminium matrix composite reinforced with nitride and oxide. The microstructural studies of the composite were carried out through scanning electron microscope, in order to examine the morphology of reinforcement and the wear surface behaviour of specimens. Tensile strength of composite increased 34% with the inclusion of 6% silicon nitride and hardness increased 60% than the base alloy. Wear resistance of composites improved considerably with the inclusion of Si3N4/MgO reinforcements.

Effects of rod-like attapulgite and lamellar kaolin reinforcement on the tribological behavior of PBO textile-resin composite liner

Textile-resin composite liners play an important role in aerospace industry owing to the self-lubrication and reinforcement. Herein, PBO (poly(p-phenylene benzobisoxazole) textile-phenolic resin composite liners reinforced with clay were prepared. Results indicated that the addition of kaolin and APL (attapulgite) have improved the wear-resistance of composites owing to the tribofilm and tribo-oxidatio layer (characterized by FIB-TEM). Clay is held together by van der Waals interactions and hydrogen bonds. During rubbing process, clay were exposed, broken and exfoliated releasing plenty of active oxygen atoms and the Si–O dangling bonds, which was contributed to the occurrence of tribo-oxidatio. Besides, ribbon-like APL performed better behavior than kaolin due to the higher specific surface area, more easy exfoliation and rolling bearing effect.

Thermal analysis and tribo‐performance evaluation of multilayered graphene and graphite based fly ash filled banana fiber reinforced brake friction composites

AbstractThis study compared thermal and tribological properties of multilayered graphene‐based flyash filled and banana fiber reinforced brake friction composites with graphite‐based specimens. Two series of brake friction composites by varying the content of graphene/graphite (1, 2, and 3 wt%) were manufactured and tribo‐evaluated using a pin‐on‐disc type tribo‐tester. Tribological properties of the brake friction composites were studied at varying test conditions of normal load (50 and 150 N) and sliding velocity (3.3 and 9.9 m/s). Compared to graphene, the thermal stability remains higher for graphite lubricated composites and decreases with increased graphite/graphene loading. The developed graphite/graphene brake friction composites resulted in a reduction in friction coefficient with increasing sliding velocity and normal loads. The graphene‐filled composite exhibited higher friction performance with enhanced wear resistance at lower sliding velocity than graphite‐based composites. The friction performance of graphite‐filled composites and the graphene‐filled composite's wear resistance remains highest at higher sliding velocity conditions. Moreover, it is observed that the wear rate of graphene lubricated composites remains 21%–35% lowers than the graphite‐filled composite. Finally, the worn composite surfaces were analyzed using a scanning electron microscopy to study the possible wear mechanisms and to understand the nature of the formed contact patches/plateaus remain vital for deciding the tribological behavior of the composites.

Evaluation of mechanical and dry sliding wear behaviour of Al 2214 aluminium alloy – graphite metal matrix composites

Aluminium metal matrix composites (AMMCs) gained an extensive popularity in different engineering fields monotonically due to their enhanced mechanical properties when compared to traditional monolithic metals. In the present investigation composites were produced using liquid metallurgy technique with modified stir casting approach with bottom pouring arrangement. Al 2214 aluminium composites have been successfully prepared with various percentage (viz. 0, 1.5, 3, 4.5, 6) of graphite reinforcement and their physical and wear behaviour have been analyzed. The experiment revealed that the amount of graphite in the matrix increased and the density reduces, hardness decreases beyond 1.5% of graphite, ultimate tensile strength and wear resistance of composites improved with increased addition of reinforcement. Optical microscope and energy dispersive X-ray (EDX) results shows uniform distribution and confirmed the existence of graphite particles in Al 2214 matrix phase.

Molecular-dynamic modeling applied for analysis of composite wear resistance increasing as compared with the original polymer matrix

The influence of filling on the mechanical properties of polytetrafluoroethylene (PTFE) was inves- tigated by molecular dynamic modeling. Molecular models of PTFE and its composite F4K20 were built. Energy values of intermolecular interaction were determined, stiffness and flexibility matrices of PTFE and F4K20 were obtained. It was shown that energy of intermolecular interaction of F4K20 is approximately 15 times higher in comparison with energy of intermolecular interaction of PTFE. Calculation based on model- ing showed that the introduction of the filler leads to a significant increase in the composite shear modulus in comparison with the initial matrix, which may be the reason of wear resistance increasing of polymer compo- sites.

Erosive wear analysis of bamboo fiber‐reinforced high‐density polyethylene composites: Effect of aluminum oxide

AbstractIn order to improve the erosive wear resistance of bamboo fiber‐reinforced high‐density polyethylene (HDPE) composites, the effect of aluminum oxide (Al2O3) on the erosive wear behavior of composites was investigated. The study of erosive wear was using the swirling water jet technique. The results showed that the addition of nanoscale Al2O3 could optimize the structural strength, composite structure, and erosive wear resistance of composites. The best erosive wear resistance was observed in composites containing 6/189 wt% of nanoscale Al2O3, 80/189 wt% of bamboo fiber, 100/189 wt% of HDPE, and 3/189 wt% of maleic anhydride grafted polyethylene. The composites with and without adding nanoscale Al2O3, both exhibited a maximum erosive wear rate at a shooting distance of 0.5 cm and an erosive duration of 180 s. The erosive wear mechanism of composites mainly included pulverization of bamboo fibers, brittle fracture of HDPE matrix, and increasing in oxygen content.

Investigation of Ti/TiB2 Composite Wear Resistance and Corrosion Resistance Coatings in Aggressive Medium and at Variable Temperatures

The present work investigates the influence of conditions like the climate of the Arctic shelf, such as aggressive medium, hydroabrasive wear and variable temperatures on Ti/TiB2 composite coatings. The applicable composite powders were investigated with the use of thermogravimetric analysis. The values of corrosion resistance and wear resistance of the coatings were also investigated.

Effects of surface wettability and thermal conductivity on the wear performance of ultrahigh molecular weight polyethylene/graphite and ultrahigh molecular weight polyethylene/graphene oxide composites

AbstractRecent studies have found a rapid increase of ultrahigh molecular weight polyethylene (UHMWPE) wear in the presence of proteins from the synovial fluid. Due to UHMWPE's high hydrophobicity, it tends to adsorb a tremendous amount of proteins. Moreover, since UHMWPE has low thermal conductivity, a temperature rise in the center of the contact area due to frictional heating could cause protein denaturation from the synovial fluid. It has been shown that the denatured protein may increase the adhesive wear response. This study aimed to address the effects of graphite and graphene oxide (GO) addition on the wear properties of UHMWPE in protein environments. The surface properties were characterized using surface roughness profiler, surface energy evaluation, zeta potential, and Fourier transform infra‐red (FTIR). Following that, wear properties of UHMWPE composite were evaluated using a multidirectional pin‐on‐disc wear test under a bovine serum lubricated condition. The worn surface of the UHMWPE composite sample was evaluated, and the dominating factors of wear properties were determined. The effect of protein adsorption on the composite surface was also assessed after the wear test. The hydrophilicity of UHWMPE/1.0GO is considered to be the dominant contribution determining protein adsorption in static conditions. UHMWPE composite's wear resistance improvement was primarily dominated by GO filler (1.0 wt%) near the sliding surface, which has improved the subsurface strength of the material and heat dissipation effect, which reduces the denaturation of the proteins.

Study of environmental behavior and its effect on solid particle erosion behavior of hierarchical porous activated carbon‐epoxy composite

AbstractPorous carbon materials have versatile physical and chemical characteristics; however, these materials are not be fully exploited as reinforcements in polymer composites. The present investigation focuses on extraction of hierarchical porous carbon and its utilization in polymer composite in order to enhance the erosion wear resistance and hardness of polymer composite. The current research work also demonstrates the wear behavior of the hierarchical porous carbon epoxy composite when exposed to different environmental conditions. The attributes of hierarchical carbon have verified through different characterization techniques, further porous carbon with optimum properties has been included as reinforcement in different ratios viz. 1, 2 and 3 wt. % to make the epoxy composites. The composites were studied for their hardness, moisture absorption and erosion wear behavior at variable impingement angles (30°, 45°, 60°, and 90°) and impingement velocities (101, 119, and 148 m/s). Moisture uptake results suggests that the increase in filler percentage increased the moisture absorption, and the highest moisture absorption was reported in composite immersed in saline water environment. It was observed that addition of activated carbon particles has enhanced hardness and wear resistance of the composite. Composite with 2 wt.% particulate reinforcement was found to be the optimum percentage of reinforcement which was subjected to 82.4% less material loss that is, erosion rate at 45° impact angle compared to neat polymer. From the erosion wear results it was further noticed that moisture absorption has deteriorated the erosion wear resistance of composites resulting in high material loss.

Microstructure, mechanical properties and wear resistance of SiCp/AZ91 composite prepared by vacuum pressure infiltration

SiCp/AZ91 composites were prepared by vacuum pressure infiltration. The microstructure, mechanical properties and wear resistance of composite were studied. Results indicated that SiC particles were uniformly distributed in the metal matrix and had a good interface bonding with the metal matrix. Mg17Al12 preferably precipitated near the SiC particles, and high-density dislocations were induced by the mismatch of the coefficient of thermal expansion (CTE) between the SiC particle and the AZ91 matrix, thereby accelerating the aging precipitation of the matrix. Compared with AZ91 alloy, the addition of SiC particles improves the hardness and compressive strength of the composite, which is mainly due to the load transfer strengthening and grain refinement strengthening mechanisms. Furthermore, a stable support surface-protecting matrix formed during the wear process because of the excellent wear resistance of SiC.

Tribological Behaviors Analysis of Synthesized Chromel Composite

This paper makes an investigation on the synthesis of tantalum carbide (TaCx) based chromel composites and their tribological behaviour using pin on disc under various load conditions. The reinforced chromel alloy with TaCx was prepared at the rate of 0, 3 and 6 wt.% of TaC using stir casting route. The wear resistance of composites was found to improve with the increase in weight percentage of TaC. The wear properties of Chromel-TaCx composite were enhanced due to the presence of 6% TaC. The wear worn out surface of chromel composite was studied through microstructures. The optimal process factors and their effect on responses have been analyzed through Response Surface Methodology (RSM) and Analysis of Variance (ANOVA).

Assessment of the tribolological behavior of a metallic tribopair: LM25 alloy-Si3N4 composites against EN 31 steel

In the present research work, tribological behavior of hard ceramic silicon nitride (Si3N4) reinforced aluminium alloy LM 25 based composites against EN 31 steel in ambient conditions at various loads (19.60–58.86 N) and sliding distances (1200–2400 m) on pin-on-disk test rig was investigated for commercial purpose of machine components. Three sets of composites were fabricated with 4–12 % of silicon nitride by stir casting technique. SEM Micrographs revealed formation of a homogeneous α-aluminum dendrites network structure developed due to the super-cooling of casting during solidification. EDS showed increased content of hard silicon and nitrogen from 29.04 to 73.96 % and 6.68–14.54 % respectively with 4–12 % reinforcement addition which led to high hardness. Increase in hardness from 58.02 to 63.70 BHN is observed with increase in reinforcement which led to reduction in wear by reducing the actual contact area during sliding whereas strength is reduced on addition of Si3N4. The wear resistance of composite is found greater with 12 % Si3N4 reinforced composite with reduced wear at low sliding distance. Due to continuous sliding, wear debris embedded with the surface forming a layer which resulted in variation in coefficient of friction (COF). COF increased at a high rate up to 1800 m followed at a slow rate up to 2400 m sliding distance with increase of normal load. SEM analysis of worn surfaces revealed removal of surface layer with generation of micro cracks with subsequent sliding in composites reinforced with 4 % and 8 % silicon nitride whereas ploughing mechanism is observed in composite with addition of 12 % Si3N4. The linear increasing trend was observed in wear loss against the dissipated energy for the investigated composites.