Tribological Properties Of Aluminium Research Articles

Evaluation of Tribological Properties of Aluminium-SiC-B4C Hybrid Composites Pages 229-234

Metallic materials are employed in most of the engineering applications involving dynamic and thermal load conditions. Different alloys of steel have been employed in industries normally owing to their higher strength, toughness and thermal properties. However, some of the technological applications demand materials with lower density, possessing suitable strength and thermal properties. Aluminium alloy is one such material with lower density and higher corrosion resistance properties compared to structural steels. The tribological properties of aluminium can be further enhanced by the addition of the ceramic materials like SiC, Al2O3, TiC, B4C etc, which have superior wear resistance characteristics. Based on the research work being carried out in the field of composite material an attempt is made to evaluate the changes in the tribological properties due to the hybrid reinforcement of material consisting of Al6061 as base alloy, SiC and B4C as reinforcement processed by stir casting method for 10% reinforcement with a combination of (2%SiC+8% B4C, 4%SiC+ 6% B4C, 6%SiC +4% B4C & 8%SiC +2% B4C). Tribological Test is being carried out with varying parameters of Load (10N to 60N), Sliding Distance (5000m) for a Constant Speed (2m/sec) for the processed materials.

A study on mechanical and tribological properties of aluminium 6061-SiC-B4C-GO hybrid nanocomposites with a novel optimized mix selection approach

ABSTRACT This research deals with the mechanical and tribological behaviour of different weight percentages of reinforcements (coated silicon carbide, boron carbide, and graphene oxide) dispersed with aluminium matrix (Al 6061) composites. The silicon carbide (SiC) was coated by Titanium oxide (TiO2) using the Electro Phoretic Deposition (EPD) method. The selected mix proportions fabrication process was performed by the stir casting method. The tribological and mechanical behaviour of hybrid aluminium matrix-composite specimens and Scanning Electron Microscopy (SEM) identification revealed that ASB-1 (86 wt% Al 6061 + 2 wt% GO + 10 wt% SiC + 2 wt% B4C) uncovered higher wear resistance and strengths due to reinforcement’s uniform distribution throughout the aluminium matrix and coating of SiC. Moreover, a comparison was performed to determine the effectiveness of hybrid composite specimens. It is concluded that the presented SRNMS framework identified the mix proportions effectively, and the coating of SiC improves the wear resistance.

Experimental optimization of tribological properties of aluminum bronze alloys made by the forging method

Aluminum bronze alloys produced by various methods are preferred materials in many fields of the industry due to their high wear resistance and good sliding properties. This study investigated the tribological properties of aluminum bronze alloys produced by forging from Cu, Al, Fe, and Mg elements. Dry sliding wear tests were carried out on a pin-on-disc wear device. Three tribological properties, wear, friction coefficient, and temperature of aluminum bronze alloys were investigated. Experimental studies were carried out for different loads, sliding speeds, and sliding ways. The factorial experiment design method was applied in the MINITprogram. A SEM visualized the samples microstructures to examine the material wear characteristics. As a result of the study, it was deter-mined that the applied load, sliding speed, and sliding way were effective parameters on the amount of wear and friction coefficient. The maximum amount of wear was 0.352 mg at 100 N load, 3 m/s sliding speed, and 3000 m sliding way conditions. The maximum temperature between materials under these conditions is 299 oC. The minimum amount of wear was obtained when 25 N load, 1 m/s sliding speed, and 1000 m sliding way were applied.

Effect of artificial aging on the tribological properties of an Al-25Zn-1Mg alloy

Abstract The tribological properties of aluminum based Al-25Zn-1Mg alloy was experimentally investigated in an MSc thesis, and the results are presented in this study. To this purpose, Al-25Zn-1Mg was commercially produced by casting. The prepared samples were divided into seven groups: no-process, solution treatment, and artificial aging for 1, 3, 6, 12 and 24 hours. Aged and untreated samples were subjected to tribological experiments under conditions of dry friction under 5 N and 10 N loads at speed of 200 rpm, 400 rpm and 800 rpm for a distance of 500 m. As a result of the tests, it was found that hardness increases in all samples depending on the aging process. It was also found that when the test speed was kept constant, the coefficient of friction increased with increasing load.

Enhancement of mechanical properties and tribological properties of aluminum using Iron(Fe) and Nickel(Ni) additives

Inmodern times it is seen that the use of aluminum alloys has increased greatly in automobile, aerospace, marine, and various other fields. This is due to the fact that aluminum alloys have superior advantages when it comes to corrosion resistance, strength to weight ratio characteristics, and high machinability when it is compared with steel. In this paper a study on the mechanical, tribological properties and microstructure of aluminum alloy with variations in Nickel (Ni) and Iron (Fe). Previous studies that have been conducted in this field have dealt with aluminum additives of different compositions with the study of only mechanical properties or microstructure. Our project deals with the study in the changes of properties and microstructure analysis of Iron(Fe) and Nickel(Ni), aluminum-based alloy added to which the tribological studies and the correlation is studied with the variations in the metal concentration, Thus the study and development of these alloys are important as it paves the way for the new generation of mechanical components with superior properties. Also, our paper deals with the fabrication of a brake disc rotor with the most suitable alloy among the three. The tensile strength, hardness, and surface characteristics of all the profiles were studied in detail and presented. The 7% of Iron powder in the profile has the highest tensile strength.

Effects of Heat Treatment on the Mechanical and Tribological Properties of Aluminium (LM6) Reinforced with Iron Oxide (Fe2O3)

This work deals with the examination of the mechanical properties of Aluminium (LM6) reinforced with iron oxide (Fe2O3). Stir casting process is used to formulate the composite sampling by varying iron oxide in 5% and 10% by weight. Three different heat treatment process of hardening, annealing and normalizing is carried out on samples of aluminium (LM6), aluminium (LM6) + 5% Fe2O3 and aluminium (LM6) + 10% Fe2O3. Composite specimens are tested to analyze the mechanical properties such as hardness, yield stress, tensile strength and elongation. Present reinforcement specks enabled the alloy to preserve higher hardness during the heat treatment. Results have shown substantial improvements in properties of the specimens with various compositions of reinforcement.

레이저 쇼크 패터닝을 통한 표면 텍스처링이 알루미늄과 강 접촉면의 마찰특성에 미치는 영향

In this study, a laser shock surface patterning process was applied to effectively transfer a micro-pattern array to an aluminum specimen. The effect of surface texturing on the tribological properties of aluminum and steel contact surfaces was investigated. In dry conditions, the friction coefficient of the contact surface could be significantly reduced through surface texturing. However, as the contact load increased, the amount of wear debris collected in the cavity became too large, and the influence of the micro-pattern on the frictional force decreased. In lubricated conditions, surface texturing significantly reduced the average friction coefficient and its variation. The effect of surface texturing became prominent in high contact load conditions due to the increase in hydrodynamic effects. Further studies considering the pattern geometry, loading conditions, and properties of the lubricant are needed to quantitatively model the coefficient of friction.

Effect of ECAP on microstructure, mechanical and tribological properties of aluminum and brass alloys: A review

Strengthening of materials with advanced techniques became very necessary to face the great developments taking place in various engineering applications. In recent years, materials with grain refinement, by severe plastic deformation (SPD) using different methods and techniques, have taken great interest. Equal channel angular pressing (ECAP) process is one of the most effective SPD techniques for producing materials with highly decreased grain size and outstanding properties. The present article discusses the effect of ECAP process on the microstructure, mechanical and wear properties of aluminum (Al) and cupper (Cu) alloys, the most common materials used for many industrial applications.

Enhancing the mechanical and tribological properties of solid cylindrical aluminum specimen by reinforcing alumina nanoparticulate through centrifuge casting technique

In this research work, solid composite cylinders of aluminum, reinforced with alumina nanoparticulate have been produced by using centrifuge casting technique, developed at our research center. The microstructure of the cast nanocomposites has been observed under Scanning Electron Microscope (SEM) and the quantitative compositional information has been obtained by using Energy Dispersive X-ray analyzer (EDX). Later, the mechanical and tribological properties of the nanocomposites with different levels of alumina nanoparticulate addition have been studied. The outcomes of the study indicate higher content of alumina nanoparticulate at the top region of the cast specimen as compared with the bottom region. Further, it was observed that, among the various specimens with different alumina nanoparticulate content addition investigated, the cast specimen with 1.5 wt% of alumina nanoparticulate addition improves the mechanical and tribological properties of aluminum.

Effect of coatings on thermal conductivity and tribological properties of aluminum foam/polyoxymethylene interpenetrating composites

The purpose of this work is to solve the problem of interface bonding in aluminum foam (AF)/polyoxymethylene (POM) interpenetrating phase composites (AF/POM). Silane coupling agent (KH-550), graphene oxide (GO), sulfonated graphene (S-GNS) and graphene (GS) coatings were prepared on the surface of AF, respectively, as an interfacial transition layer. The molten modified POM(POMC) was injected into the hole of coated AF by injection molding to prepare different kinds of coated AF/POMC. Thermal conductivity, friction coefficient and wear loss of coated AF/POMC were analyzed, and the wear mechanisms were discussed in detail based on evidences from SEM. The effect of coatings on thermal conductivity of coated AF/POMC was also verified by ANSYS. The investigation has shown that four kinds of coating are successfully covered on the surface of AF, respectively, and the morphology of S-GNS coating is the smoothest. The thermal conductivity of coated AF/POMC is higher than that of AF/POMC. The thermal conductivity of S-GNS-AF/POMC reaches the highest value of 2.25 W m−1 K−1, because S-GNS coating plays a role in reducing the thermal resistance of the interface between AF and POMC phases. The friction coefficient and wear loss of coated AF/POMC are also lower than that of AF/POMC. Three types of graphene coating(S-GNS,GO,GS) as an interface transition layer between AF and POMC phases can homogenize friction, accelerate heat transfer and reduce the friction coefficient and wear loss of composites. Through ANSYS thermal steady-state simulation, S-GNS-AF/POMC has the maximum number of heat flow paths and the highest heat flux compared with other materials.

Tribological Properties of Aluminum and Silicon Borides at High Temperatures

In our present study, AlB12 and SiB6 plate specimens prepared by spark plasma sintering AlB12 and SiB6 powders, respectively, and their tribological properties were investigated in the temperature range of 25°C to 1000°C in air. Also, the micro Vickers hardness of the AlB12 and SiB6 plate specimens were evaluated in the temperature range of 25°C to 1000°C in an Ar gas atmosphere. It was found that both the steady friction coefficients of the AlB12 and SiB6 plate specimens were as low as 0.07 to 0.08 at 1000°C. According to XPS analyses, it was found that Al2O3 and B2O3 films were observed on the worn surfaces of the AlB12 plate specimens after sliding at 1000°C. On the other hand, SiO2 and B2O3 films were observed on the worn surfaces of the SiB6 plate specimens after sliding at the same temperature. It was also found that both the boride plate specimens exhibited micro Vickers hardness as high as 20 GPa in the temperature range of 25°C to 1000°C.

Study and comparison of A356-WC composite and A356 alloy for an off-road vehicle chassis

Every vehicle manufactured has a chassis design that corresponds to its body shape, size and material used, to its performance. Aluminium alloys are most commonly used due to its high strength to weight ratio. Recent studies reveal that addition of reinforcements enhance the mechanical and tribological properties of aluminium and its alloys. So in this study, keeping aluminium (A 356) alloy as the matrix, WC particulates were added at 4 wt.% to the matrix using stir casting technique. The composition and microstructure of the cast specimens were studied by using EDS and SEM. The Vickers hardness test was carried out on both as-cast and heat treated specimens. The inference was that the composite had no effect on the heat treatment. A sample design of a roll cage chassis of an off-road vehicle was designed in Solidworks. Computer Aided Engineering (CAE) analysis was carried out on both composite and A 356 alloy chassis. The analysis showed that the composite was a better choice of material selection than the conventional aluminium alloy for its improved impact resistance and high strength to weight ratio and design safety.

Selective Modification of the Tribological Properties of Aluminum Through Temperature and Dose Control in Oxygen Plasma Source Ion Implantation

Improvements in the tribological properties of pure aluminum and “aeronautical” alloy AA7075-T651 were obtained by oxygen-ion implantation [(0.7 to 5) × 1017 O/cm2, 30 keV] using our pulsed electron cyclotron resonance plasma source. This oxygen plasma source ion implantation process produced oxide nanoprecipitates that enhanced the hardness up to three times in the surface layer and caused reductions in the scratch depths and the friction coefficients by similar factors. A spectrum of tribological properties was obtained depending on temperature and ion dose. Temperature measurement and control were obtained through an integrated thermocouple and by changing the duty-cycle of the microwave source. The oxygen content and the depth-resolved chemical composition were measured and optimized using x-ray photoelectron spectroscopy (XPS) combined with Ar-ion etching. The tribological properties were investigated by (i) depth-sensing nanoindentation for hardness and Young's modulus, (ii) scratching and scratch-depth measurement via atomic force microscopy (AFM), and (iii) friction force measurements using AFM. Low-temperature (≤160°C) implantations with optimal O-ion doses produced, in both pure and alloyed Al, an approximately 50-nm-thick, smooth, and extremely fine-grained metal–alumina nanocomposite. The resulting surface was hard and stiff but nonbrittle and displayed high scratch resistance and low friction. High-temperature (~430°C) implantation had different effects on pure Al and AA7075. On pure Al, it produced a very hard but brittle Al2O3 layer for which yield points (displacement excursions) were observed at critical load values in the nanoindentation force–displacement curves. On AA7075, XPS chemical profiling revealed an effect of extreme Mg surface segregation and complete Al surface depletion; MgO crystallites formed a rather rough but surprisingly thick layer (>100 nm). The resulting AA7075 surface showed a hardness increase that was substantial but slightly smaller than that obtained at low temperature.

Effects of ion implantation and plasma treatment on tribological properties of aluminium and Al-Mg alloy

Nitrogen ion implantation and plasma treatment, such as ion nitriding and electron cyclotron resonance (ECR) plasma nitriding, were carried out on pure aluminium and Al-Mg alloys and the tribological properties of the resulting samples were studied. Combined surface treatments, ion nitriding or ECR plasma nitriding, were also conducted after ion implantation. It was found that the Vickers hardness of treated samples increased for both pure aluminium and Al-Mg alloy. The friction coefficient decreased after each treatment in the case of pure aluminium. It was found that nitrogen implantation was effective. The wear volume was also decreased, and the combined treatment of ion implantation and ion nitriding was found to be most effective in decreasing the wear volume of pure aluminium. Scanning electron and transmission electron microscopies of ion nitrided aluminium, treated after implanting, revealed a surface consisting of AlON and AlN+Al layers. For the Al-Mg alloy, ECR plasma nitriding was found to be effective in decreasing the friction coefficient and the wear volume.