Wear Rate Values Research Articles

Investigation on red brick dust filled epoxy composites using ant lion optimization approach

This article reports on the characterization and erosion wear performance of a new class of epoxy composites filled with micro‐sized red brick dust (RBD) particles. Although a number of ways for its utilization have been suggested in the past, its potential as a filler material in polymeric matrices has not yet been explored so far. In this work, composites with different RBD content are prepared by simple hand layup technique. The composites are characterized in regard to their density, porosity, micro‐hardness, and strength properties. Solid particle erosion trials are conducted following a well‐planned experimental schedule based on Taguchi design‐of‐experiments. The morphology of composite surfaces is then examined by scanning electron microscopy. Furthermore, a novel nature‐inspired ant lion optimizer (ALO) algorithm is proposed in this work to achieve minimum erosion wear rate. This algorithm mimics the behavior of antlions in nature. It provides a very competitive result over other evolutionary algorithms due to its characteristics like improved exploration, avoidance of local optima, quick convergence and less number of tuning parameters. The wear rate value obtained by ALO exhibit the lowest one as compared to the traditional Taguchi result. POLYM. COMPOS., 40:3877–3885, 2019. © 2019 Society of Plastics Engineers

A comparative study of dry sliding wear characterization of nano SiC and nano B4C filled Al7075 nanocomposites under high temperature environment

The present work investigates the sliding wear behavior of aluminum matrix nanocomposites (AMNCs) fabricated through ultrasonic cavitation-assisted casting technique. The boron carbide (B4C) and silicon carbide (SiC) nanoparticles of average size 80 nm are used as a reinforcing material and the Al7075 aluminum alloy is used as matrix material. The microstructure confirms uniform distribution of nanoparticles throughout the matrix. Hardness and tensile strength of fabricated composites increase with the addition of nano fillers. The dry sliding wear of developed nanocomposite is studied on high temperature pin disc tribometer. In order to analyze the coefficient of friction (COF) and wear rate certain parameters like normal load, parentage reinforcement of fillers, sliding velocity and pin temperature are considered as input parameters. The results obtained shows that wear rate and COF are directly proportional to pin temperature (30 °C–150 °C), normal load (5–15 N) and sliding velocity (1.5–2.5 m s−1) while the wear rate and COF values are inversely proportional to percentage reinforcement (0.75%–2.25%). Worn surface of nanocomposites is also analyzed through SEM analysis.

Microstructure and Tribological Performance of Alumina–Aluminum Matrix Composites Manufactured by Enhanced Stir Casting Method

Al–Zn–Mg–Cu matrix composites reinforced with (0–20 wt %) Al2O3 particles have been manufactured by enhanced stir casting technique. Microstructural characterization of cast composites by optical, field emission scanning electron microscope (FESEM), energy dispersive X-ray (EDS) and X-ray diffraction (XRD) reveals homogeneous distribution of reinforcements in Al-alloy matrix with MgZn2 plus Al2CuMg intermetallics. With increasing particle content, hardness of composite rises considerably in spite of marginal rise in porosity. Tribological performance under two-body abrasion has been studied considering central composite design (CCD) apart from identification of mechanisms of wear via characterizations of abraded surfaces and debris. Composites exhibit significantly reduced wear rate and coefficient of friction (COF) irrespective of test conditions, since mechanisms of abrasion are observed to change from microplowing and microcutting in unreinforced alloy to mainly delamination with limited microplowing in composites. Effects of four independent factors (reinforcement content, load, abrasive grit size, and sliding distance) on wear behavior have been evaluated using response surface-based analysis of variance (ANOVA) technique. Dominant factors on both wear rate and COF are identified as reinforcement content followed by grit size and load. Combined optimization of wear rate and COF employing multiresponse optimization technique with desirability approach as well as regression models of individual responses have been developed, and their adequacies are validated by confirmatory tests. The developed mathematical models provide further insight on the complex interactions among wear performances of the selected materials and variables of abrasive system. The optimum amount of reinforcement is identified at around 15 wt % for achieving the lowest values of both wear rate and COF.

Dry sliding wear behaviour of β-type Ti-Nb and Ti-Mo surfaces designed by diffusion treatments for biomedical applications

The dry sliding wear behaviour of different Ti-Nb and Ti-Mo surfaces was investigated in order to evaluate the role of Nb and Mo β-stabilizing elements in titanium wear resistance to consider them for biomedical applications. Dry sliding wear tests were performed under unlubricated conditions using a ball-on-plate tribometer (UMT) with reciprocating lineal movement of 1 Hz frequency at different loads (2 and 5 N) and against two counterface materials (alumina and stainless steel) to assess the effect of these parameters on wear.The results indicated an improvement in wear resistance for all the modified Ti surfaces. Metal-on-metal surfaces exhibited higher wear rate than ceramic-on-metal, and higher wear was observed for the more severe conditions. Wear rate values on modified surfaces were between 53% and 96% lower compared to pure Ti tested at 2 N, and up to 79% lower than Ti at 5 N. In both cases the highest wear reduction was observed for Ti-MoNH4Cl surface.

Effect of quench-tempering conditions prior to nitriding on microstructure and fretting wear mechanism of gas nitrided X210CrW12 steel

In this research the effect of quench-tempering conditions prior to industrial gas nitriding on the microstructure, fretting wear behavior and mechanism of nitrided X210CrW12 steel was investigated. The results reveal that higher tempering temperature can increase the thickness of the compound layer and the diffusion layer, and the amount of nitride precipitates also increases. The specimen tempered at the lower temperature has a thinner compound layer but a higher nitrided layer hardness. In addition, decarburization occurs during the nitriding process. The wear mechanism is also explained by the FEA wear model. The thickness of compound layer and the hardness of diffusion layer are the main factors that influence the wear behavior of the nitrided specimens. Increasing the wear resistance of counter material leads to the transition of wear mechanism from slight adhesion to severe abrasion. When the counter material is GCr15, all nitrided specimens present the similar wear rate values, while the wear rate of the specimen with the higher diffusion layer hardness and thinner compound layer tempered at the lower temperature of 550 °C is lowest when the counter material is SiC.

Wear and hardness behavior of antimony-modified al-si-mg alloy under multiple thermal ageing condition

The wear and hardness property of thermally aged antimony-modified A356-type Al-Si-Mg alloy produce through sand casting process has been investigated. The antimony (Sb) was added in a trace amount (0.01%) to modify and cause refinement of microstructure which led to an increase in hardness with a decrease in wear loss of the alloy. The study involve production of antimony-modified Al-Si-Mg alloy, thermal ageing treatment, wear test, hardness measurement, microstructure and surface morphology examination. Five samples of the produced alloy were subjected to solution heat treatment (T6) at 540 o C for a soaking time of 1hour, quenched in warm water, 40 o C and then subjected to thermal ageing treatment at 120 o C for 1-4hours at one hour interval. One of the samples was further aged at 180 o C for a soaking time of 2hours. The samples were then subjected to wear test using Anton paar wear testing machine and the wear rate was found to be decreasing as the soaking time is increased. The wear rate value decreases from 0.1223mm 3 /N/m (control) to 0.003909mm 3 /N/m (for soaking time of 4hours at 120 o C) indicating a decrease of 68.04%. The hardness value increases from 4.91 (control) to 8.43 (for soaking time of 4hours at 120 o C) indicating an increase of 41%. Improvement in hardness value can be attributed to fine coherent clusters precipitate which serves as obstacles to the movement of dislocation. SEM micrograph shows the wear track of the specimen with the least wear lost while optical microscopy was used to reveal the microstructure of all the samples used. Keyword: Aluminium alloys, Pre-ageing treatment, GP zones, Soaking time, engineering materials

Characterization of LaB6 particulate-reinforced eutectic Al-12.6 wt% Si composites fabricated via mechanical alloying and spark plasma sintering

In this study, x wt% LaB6 (x = 0, 2, 5 and 10) particulate-reinforced eutectic Al-12.6 wt% Si powders and composites were prepared from commercial Al, Si and LaB6 starting materials via powder metallurgy methods. Mechanical alloying (MA) was conducted on the blended powders using a high-energy ball mill (at 1060 cycles/min) for 2, 4 and 8 h. Mechanically alloyed (MA'd) powders were subjected to cold pressing (CP, under 450 MPa) and spark plasma sintering (at 450 °C for 180 s) processes. Powder particle morphologies changed from flaky to semi-equiaxial shape after MA duration of 4 h. Calculations performed through the XRD patterns of Al phase revealed that the average crystallite size increased and the average lattice strain decreased with increasing MA duration and LaB6 content. Spark plasma sintered (SPS'd) samples were examined in terms of composition, microstructure, densification and mechanical properties (hardness, yield strength, compressive strength and wear volume loss). Studies revealed that 4 h was the optimal MA duration and 10 wt% was the optimal reinforcement content for the LaB6particulate-reinforcedAl-12.6 wt% Si composites with respect to their mechanical properties. Al-12.6 wt% Si-10 wt% LaB6 sample had the highest hardness (1.72 ± 0.12 GPa), yield strength (373 MPa), compressive strength (578 MPa) and lowest wear rate (0.001 mm3/Nm) values among all SPS'd samples.

Optimization of Process Productivity for Multi Phase Carbon Nanotubes (CNT) Reinforced Nanocomposites Using Taguchi-Fuzzy Model

The present work is focused on the processing and machining of multiphase carbon nanotubes reinforced nanocomposites. In this work the author has performed electric discharge machining on multiphase carbon nanotubes reinforced nanocomposites. Optimal combination of different process parameters have been decided determined for maximum material removal rate and minimum tool wear rate which results the improvement in productivity of the complete process. In this study four different process parameters (Peak current, gap voltage, pulse on time and duty cycle) are used and the most significant parameter is illustrated. In the present work, the factor material removal rate has been considered as productivity measure. The goal is to determine the best process condition for maximizing material removal rate and simultaneously for minimizing the tool wear rate values, which may be considered as multi-response optimization problem. Taguchi method is a well known optimization technique used for optimizing the single objective function. Consequently the conversion process of objective functions invites ambiguity, uncertainly etc. into the computation. These implications always arises the need to correlate various responses. Hence to overcome these implications a fuzzy reasoning of multiple performance characteristics has been developed. This results in the transformation of multi performance characteristics in single multi-performance characteristics (Productivity) and can be optimized using Taguchi method. Using Taguchi’s design of experiment methodology optimal combination of process parameters will be obtained for various performance measures. Process productivity Optimize using the Fuzzy logic approach and the optimal results were also validated.

Tribo-performance enhancement of PAEK composites using nano/micro-particles of metal chalcogenides

While designing the ambitious advanced composites based on PAEK (50 wt%), glass fibers (30 wt %) and natural graphite (10 wt %), it was proposed to include one more solid lubricant (10 wt %) from the category of metal chalcogenides. Particles of MoS2 and WS2 in micron and nano-sizes were selected for inclusion in combination with natural graphite. The themes for investigations were; which one is the better performer amongst MoS2 and WS2, and nano-particles can impart beneficial effect or not; and the last how efficient would be these tribo-composites in terms of friction, wear resistance and PVlimit values. The composites were characterized in detail for physical, mechanical, thermal and tribological performance. The WS2 proved more beneficial till moderate PV conditions but not for severe conditions as compared to MoS2. The composites proved excellent tribo-materials in terms of low friction (∼0.04), wear rate (2.2 × 10−16 MPa m/s) and PVsafe values (84 MPa m/s). The chemistry of the counterface surface was studied using X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy (RS) while the morphology of the worn pins surface and counterface surface was observed using a combination of 3D profilometer and scanning electron microscopy.

Effect of MWCNTs addition on the wear and compressive deformation behavior of LM13-SiC-MWCNTs hybrid composites

Abstract Aluminium-SiC-MWCNTs nano-hybrid composites (HCs) were prepared through stir casting technique. The wear rate, coefficient of friction and compressive strength of HCs increase with increasing MWCNTs (multiwalled carbon nanotubes) concentration in aluminum SiC comopsites. But when only MWCNTs are used as reinforcement its strength, wear rate and microhardness values are found to be significantly less than other studied composite materials. Therefore, SiC is used as a secondary reinforcement to enhance the interfacial interaction between MWCNTs and Aluminium. This interaction improved strengthening of matrix due to uniform dispersion of MWCNTs and high mechanical strength of SiC and MWCNTs. When MWCNTs are used separately as reinforcement, it got agglomerated and thus the strength and wear resistance of composite decreased.

Optimization in tribological behaviour of Al-nanoTiO2 powder metallurgy composites using response surface method

The Al- nano TiO2 composite processed powder metallurgy and wear behaviour was experimentally investigated on aluminium with combined nano TiO2 weight percent reinforcement of 4%,7% and 10% at different sliding velocity of 1.5 m/s,2.0 m/s,2.5 m/s and different normal loads of 10N,30N,50N. The effect of specific wear rate and co efficient of friction optimised by response surface method. The results predicted by the developed model are concurring well within the measured values. The correlation co-efficient of model, regarding the specific wear rate and co efficient of friction, were about 0.96 and 0.94 respective with conform the degree of accuracy of the mathematical model. The optimal condition attain the minimum specific wear rate and co-efficient of friction at sliding velocity 2.04 m/s and Normal load 13.5 N with Al- TiO2 10% weight. The predicted value of specific wear rate 1.08e−7 and co efficient of friction 0.31 respectively.

Evaluation of Mechanical and Tribological Properties of Glass/Carbon Fiber Reinforced Polymer Hybrid Composite

Polymer matrix composites used in different industrial applications due to their enhanced mechanical properties and lightweight. However, these materials are subjected to friction and wear situations in some industrial and automobile applications. Therefore, there is a need to investigate the wear properties of polymer matrix composite materials. This article emphasizes the dry abrasive wear behavior of a hybrid glass/carbon ([GCGGC]S) composite. The mechanical and wear properties of the composite was evaluated and compared with maiden glass and carbon fiber reinforced polymer composite. Design of experiment of Box-Behnken type was adopted to perform the experiments. Response surface methodology (RSM) was employed to optimize the experimental parameters to minimize the specific wear rate of the composites. A second order mathematical model was developed. The model has predicted the optimum input parameters for minimum specific wear rate of 18.847×10-3 mm3/Nm for the hybrid ([GCGGC]S) composite. Furthermore, the model predicted specific wear rate value was validated with experimental one and found a close agreement between them.

Hardness and wear rate of Al LM6 hollow cylinder fabricated using horizontal centrifugal casting

Horizontal centrifugal casting is one of the methods to produce functionally graded materials (FGMs). The pouring temperature and rotational speed of the mold are among the main parameters affect the quality of casting. The effect of these two casting parameters on the hardness and wear properties of the Al LM6 hollow cylinder fabricated are investigated. The hardness value along the radial direction of the Al LM6 hollow cylinder fabricated is measured using Micro Hardness Vickers test. Meanwhile the wear rate of Al LM6 hollow cylinder fabricated is determined by measuring the mass loss after loaded with 5 N force and sliding distance of 75 m on silicon carbide grit paper (200 µm). The result after the testing shows that the Al LM6 hollow cylinder which is fabricated at pouring temperature 725°C and motor speed of 1500rpm produces the highest hardness sample and the cylinder fabricated at pouring temperature 690°C and motor speed of 1700rpm have the lowest wear rate value.

Tribological Properties of Nanoclay Reinforced Polyamide‐6/Polypropylene Blend

In this study, the tribological performance of polyamide‐6 (PA‐6), polypropylene (PP), polyamide‐6/polypropylene (PA‐6/PP) polymer blend, and nanoclay reinforced polyamide‐6/polypropylene composite are investigated. Nanoclay reinforced polymer composite is produced by melt compounding using co‐rotating twin screw extruder followed by injection moulding. Tribological studies are carried out using a pin‐on‐stainless steel disc configuration under dry sliding conditions. Tribological tests are carried out at sliding speed of 0.5 m s−1 and applied load values of 25, 50,100, 150 N. The friction coefficient and specific wear rate values are obtained and evaluated. The results show that the addition of nanoclay into the PA‐6/PP polymer blend reduced their coefficient of friction and specific wear rate values. The lowest coefficient of friction and specific wear rate values are for nanoclay reinforced PA‐6/PP blend. The highest coefficient of friction and specific wear rate values are for PA‐6 polymer.

Optimization of wear and friction characteristics of Phyllanthus Emblica seed oil based lubricant using response surface methodology

The escalating prices, rapid diminution of fossil fuels, tenacious regulations of the authorities, etc. enforced towards the alternate biogenic fuel for lubrication. The present study assessed the lubricity characteristics of Phyllanthus Emblica seed oil based lubricants by using a pin on disc (POD) tester. The design of experimentations has been carried out using response surface methodology (RSM). The value of parameters such as blend ratio, load and sliding speed ranges from 0 to 20%, 50 to 100 N and 1.3 to 3.8 m/s, respectively, are used to assess the value of specific wear rate (SWR) and coefficient of friction (COF). Test results illustrate that the adhesive wear occurred during the experiments. It has been observed that AB10 shows the probable results in terms of wear and friction characteristics as compared to other lubricant variants at low load and high sliding velocity conditions and perform as an excellent lubricant additive. This contributes towards the replacement of petroleum based lubricants. Analytical ferrography and total acid number (TAN) analysis of the used oil was also done to study the wear debris in the oil.

The structural, magnetic, and tribological properties of nanocrystalline Fe-Ni permalloy and Fe-Ni-TiO2 composite coatings produced by pulse electro co-deposition

In this study, nanocrystalline Fe-Ni permalloy and Fe-Ni-TiO2 composite coatings were prepared by pulse electrodeposition technique and the effect of current density at five levels was investigated. Morphology of the surface, chemical composition, microstructure, magnetic behavior, hardness and wear properties of the coatings were studied by means of SEM, EDS, XRD, VSM, Vickers microhardness tester and the wear testing instrument of pin-on-disk type. The results showed the mixture morphologies of small needles and fine cauliflower for the coatings prepared at low current densities. Ni content increased in expense of Fe content due to anomalous deposition at higher current densities and the amount of TiO2 nanoparticles in the coatings were also increased. X-ray diffraction patterns showed BCC structure as the dominant phase. However, by increasing the current density, two phase structures of BCC and FCC were detected. It was observed that the current density has a positive effect on grain refinement of Fe-Ni and Fe-Ni-TiO2 coatings. The results of VSM measurements demonstrated that the saturation magnetization (Ms) decreased and coercivity (Hc) increased by increasing the current density due to a reduction of Fe content and grain size. The highest saturation magnetization and lowest coercivity were obtained at 10 mA/cm2 for all coatings. Saturation magnetization values for the Fe-Ni-TiO2 coatings were lower than those of the Fe-Ni coatings. Moreover, the wear resistance and hardness of the coatings can be largely improved by reducing the grain size and Fe content in Fe-Ni matrix. Also, the friction coefficient and the wear rate values of Fe-Ni-TiO2 coatings were lower than those of Fe-Ni coatings due to the grain refinement and dispersion strengthening mechanisms. The adhesive type mechanism and the wear debris were observed on the worn surface of Fe-Ni coatings. While by increasing the TiO2 nanoparticles, the abrasive grooves and wear debris on the worn surface were reduced and the worn surfaces of coatings showed both adhesive and abrasive wear mechanisms.

Study of some Mechanical Properties and Erosive Behavior by Taguchi Method for Hybrid Nano Composites

The aim of this research is study the effect Nano TiO2 powder on impact strength, fracture toughness, hardness shore (D) and erosive wear behavior of polymer composites materials are prepared by simple hand lay-up technique. The specimens was prepared by adding (1%, 2%,3%,4%,5% & 6%) weight fraction of nano powder (TiO3) has average size of (16 nm) to unsaturated polyester resin reinforcement with (5%) weight fraction of carbon fiber. The value of erosive wear rate for polymer composite materials can be obtaining after (15 hours) and under effect various parameters such as impingement angle (30 º, 45 º, 60 º, 90º), erodent size of sand silica (300, 400 ,500,600 μm) and stand-of distance (17, 19, 21,23 cm). Also in this research study effect of parameters on erosive wear rate by the used of Taguchi orthogonal arrays L16. The results show the maximum value of impact strength , fracture toughness and hardness (shore D) was founded at specimen (89% UP +5% C.F+6% TiO2) also this specimen has the best resistance to erosive wear rate under parameters (23cm stand- off distance , 300 μm erodent size of sand silica , 60 º impact angle) than other specimens. From analysis of variance (ANOVA) the filler content and impingement angle factor have more effect on erosive rate while the stand-off distance and erodent size of sand less effect on erosive wear rate .

Sintering and tribomechanical properties of gel-combustion-derived nano-alumina and its composites with carbon nanotubes

Fully pure nano-α-alumina (Al2O3) was prepared following gel-combustion method. Near theoretically dense monolithic Al2O3 and its composites reinforced with multiwalled carbon nanotubes (MWCNTs) were prepared using spark plasma sintering (SPS) at 1500 °C under 40 MPa within 10 min. The shrinkage curves were guided in sequence by the crystallization of the amorphous mass followed by a solid-state sintering. The differential nature of electrical conductivity of both composite phases resulted in enhanced densification through localized joule heating. Formation of ~ 1-μm-sized equiaxed matrix grains with uniform distribution of structurally survived CNTs in it was observed in the sintered composites. Within the investigated loading span, the highest Vickers hardness (HV) values were obtained only at 0.5 wt% MWCNT loading in matrix Al2O3. Improvements in HV values for the composites at 0.2 and 2 kgf indentation loads were found to be ~ 18 and ~ 12%, respectively, in comparison with those obtained for pure matrix phase. Quantitative indentation size effect analyzed through standard mathematical models indicated the role of matrix grain refinement and proper matrix–filler load sharing in changing the true hardness. On the contrary, increased CNT concentration leaded to increased sensitivity toward size effect due to the extreme flexible nature of the filler. Unlubricated linear scratch experiments revealed ~ 30–45% lower specific wear rate (WR) values of the composite specimens compared to SPS-processed monolithic Al2O3. Microstructure and scar profile observations were utilized to describe such enhanced wear resistance of present composites.

INVESTIGATION CORROSION AND MECHANICAL PROPERTIES OF CARBURIZED LOW CARBON STEEL

In this research, Taguchi method is used (S/N) ratio for measuring the variations in experimental design. Taguchi designs used in converting the multi-performance problem into a single-performance problem for experiments which will are in building (Taguchi (L27) orthogonal array) for carburization operation. The main variables that had a great effect on carburizing operation are Carburization temperature (o C), carburization time (hrs.) and tempering temperature (oC). It was focused also on calculating the amount of carbon penetration, the value of hardness, wear rate, corrosion rates and optimal values obtained during the optimization by (Taguchi) approach method for multiple parameters. In this study, the carburization process was done in temperature between (850 to 950 ᵒC) for (2 to 6 hrs.). Quenching process was done for the specimens after heat treatments in furnace chamber by different quench solution (water, salt and polyvinyl alcohol). Taguchi design used to achieve maximum hardness and depth penetration, Minimum wear and corrosion rates.

Wear rate optimization of Al/SiCnp/e-glass fibre hybrid metal matrix composites using Taguchi method and genetic algorithm and development of wear model using artificial neural networks

Studies on wear properties of Aluminium based hybrid nano composite materials, processed through powder metallurgy technique, are reported in the present study. Silicon Carbide nano particles and E-glass fibre are reinforced in pure aluminium matrix to fabricate hybrid nano composite material samples. Pin-on-Disc wear testing equipment is used to evaluate dry sliding wear properties of the composite samples. The tests were conducted following the Taguchi’s Design of Experiments method. Signal-to-Noise ratio analysis and Analysis of Variance are carried out on the test data to find out the influence of test parameters on the wear rate. Scanning Electron Microscopic analysis and Energy Dispersive x-ray analysis are conducted on the worn surfaces to find out the wear mechanisms responsible for wear of the composites. Multiple linear regression analysis and Genetic Algorithm techniques are employed for optimization of wear test parameters to yield minimum wear of the composite samples. Finally, a wear model is built by the application of Artificial Neural Networks to predict the wear rate of the composite material, under different testing conditions. The predicted values of wear rate are found to be very close to the experimental values with a deviation in the range of 0.15% to 8.09%.