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The main goal of the present study is to investigate the friction and wear behaviors of aluminum matrix composites with an A360 matrix reinforced with SiC, B₄C and SiC/B₄C particles.

Un‐reinforced aluminum casting alloy, Al/SiC, Al/B₄C and Al/SiC/B₄C aluminum composites were prepared for the present study. Friction and wear tests of aluminum and its composites versus AISI316L stainless steel were carried out for dry sliding condition using by a pin‐on‐disc arrangement. Tests were realized at the sliding speed of 0.5, 1.0 and 1.5 ms⁻¹ and under the loads of 10, 20 and 30 N. The microstructures of the present composites were examined by scanning electron microscopy and energy dispersive spectroscopy analysis.

The coefficient of friction of the composites is approximately 25‐30 percent lower than that of the un‐reinforced aluminum. The specific wear rate of the aluminum and its composites decreases with the increase in load and increases with the increment of sliding speed. Un‐reinforced aluminum has specific wear rate value of 1.73×10⁻¹³ which is the highest specific wear rate, while Al+17%SiC has specific wear rate value of 2.25×10⁻¹³ m² N⁻¹ which is the lowest specific wear rate among the tested materials. The average specific wear rates for Al+17%B₄C, Al+17%SiC/B₄C and Al+17%SiC composites are obtained about 49, 79 and 160 percent lower than aluminum wear rate under the same test conditions, respectively.

In the present study, composites were prepared by pressured infiltration technique. The employed composites are important in industry due to their higher wear resistance, light in weight and less thermal distortion comparing to conventional composites. Also, wear behavior of Al/B₄C, Al/SiC/B₄C and Al/SiC composites produced by pressured infiltration technique were not studied very much earlier, therefore more explanation about these composites were proposed.

The aim of the research is to investigate wear performance of some phenolic composites with boric acid.

The brake lining which has new formulation has been produced by using various additive materials. Various techniques have been used in the production of brake lining. These phenolic composites were subjected to friction and wear tests under different loads, and changes in the hardness and microstructures were examined.

As a result of this study, the following findings are reported. It was not found a direct proportionality between hardness and wear resistance due to the complexity of composite structure. Heat treatment application changed the microstructure of the brake lining, and increased the hardness and also decreased the density. With the increasing of temperature, the ingredients in the braking pad were affected other due to faster diffusion. On the other hand, hardness of specimen increases due to heat treatment and also specific wear ratio changes. As a filling material, barite was used due to better performance in the environmental conditions. More wear was observed in the bigger powder particles comparing to the smaller ones due to more structural loss. Squealing was heard in fiber un‐reinforced brake lining due to more barite content. In the present samples, boric acid deports the water and establishing the structural equilibrium. Therefore, these samples supplied higher and stable friction of coefficient. Also, heat treatment supplied a stable friction coefficient. With the increasing of copper powder into specimens, friction coefficient also increased. Heat treatment made the increment of hardness of specimens and also it made effect on the hardness with strengthening bonds of interparticles.

Limitations in the present research are as follows: two different pressures and eight different temperatures were used and brake linings were subjected to wear test, hardness tests, microstructures were examined.

For future work, instead of buying expensive brake lining, new and cheaper phenolic linings are produced. By this process, economic benefit can be gained and also environmental protection can be succeeded in producing such asbestos free brake linings.

This paper fulfills an identified information and offers practical help to the industrial firms working with brake lining and also to the academicians working on wear of materials.

The present study aims to find out the best polymer/polymer pair in electrical insulating applications. Moreover, the effects of different polymer counterpart and applied load on the friction and wear behaviour of PA 46 + 30%GFR and unfilled PA 66 thermoplastic polymers are to be studied.

Friction and wear tests vs PA 46 + 30%GFR and PPS + 30%GFR polymer composites were carried out on a pin‐on‐disc arrangement and at a dry sliding conditions. Tribological tests were performed at room temperature under 20, 40 and 60 N loads and at 0.5 m/s sliding speed.

The results showed that, the coefficient of friction decreases with the increasing of load (up to 40 N) for PA 46 + 30%GFR composite and polyamide (PA) 66 polymer used in this study. However, above 40 N applied load the coefficient of friction increases. The specific wear rate for PA 46 + 30%GFR and PA 66 against PPS + 30%GFR polymer composite counterpart are about in the order of 10⁻¹³ m²/N while the specific wear rate for PA 46 + 30%GFR and PA 66 against PA 46 + 30%GFR polymer composite counterpart are in the order of 10⁻¹⁴ m²/N. For PA 46 + 30%GFR composite and unfilled PA 66 polymers tested the specific wear rate values increased with the increment of load. The highest specific wear rate is for unfilled PA 66 against PPS + 30%GFR with a value of 2.81 × 10⁻¹³ m²/N followed by PA 66 against PA 46 + 30%GFR with a value of 2.26 × 10⁻¹³ m²/N. The lowest wear rate is PA 46 + 30%GFR polymer composite against PA 46 + 30%GFR polymer composite counterpart with a value of 3.19 × 10⁻¹⁴ m²/N. The average specific wear rates for unfilled PA 66 against PA 46 + 30%GFR is 80 times higher than PA 46 + 30%GFR wear rate while specific wear rates for unfilled PA 66 against PPS + 30%GFR is 100 times higher than that of PA 46 + 30%GFR wear rate. From point view of tribological performance, PA 46 + 30%GFR is a more suitable engineering thermoplastic composite materials for electrical contact breaker applications.

In the present work, tribological tests were performed only at room temperature under three different loads and a sliding speed. This is the limitation of the work.

This work is easily used for industrial polyamides to check their tribological behaviours.

This is an original and experimental study and it will be useful both for academicians and for industrial sides.

Previously, the effect of pore-forming agents on the properties of pore size and morphology was studied. In this paper, we determine the optimal combination of parameters by tensile strength and perform tribological tests with optimal combination of parameters.

In this paper, porous polyimide (PI) materials were fabricated using vacuum hot molding technology. The orthogonal experiment was designed to test the mechanical properties of porous PI materials with the process parameters and the content of pore-forming agent as the changing factors. The porous PI oil-bearing materials were obtained by vacuum immersion, and tribological test were carried out.

The results showed that porous PI oil-bearing materials are suitable for low-speed and low-load conditions. The actual value of the friction coefficient basically match with the theoretical value of the regression analysis, and the errors of the friction coefficient are within 10% and 3%, respectively, which proves that the method used in the study is feasible for the friction coefficient prediction.

In this paper, we have produced a new porous oil-bearing material with good tribological properties. This study can effectively predict the friction coefficient of PI porous material.

The aim of the research is to investigate the ceramic brake lining on the brake performance.Design/methodology/approach – The brake lining which has new formulation has been produced by using various additive materials. Various techniques have been used in the production of brake lining. These ceramic linings were subjected to friction and wear tests under different loads, and changes in the hardness and microstructures were examined.Findings – As a result of this study, the following findings are reported. A direct proportional was not found between hardness and wear resistance due to the complexity of composite structure. Kevlar fibers were homogeneously distributed in the matrix and therefore, very few microvoids were observed in the structure. Similarly, stone wool was well spread out the braking pad and hence decreased the microvoids' occurrence. Heat treatment supplied more homogeneous structure and hence, microstructural variations were minimised during the brake action. On the other hand, heat treatment decreased the hardness of glass fiber reinforced specimens and increased the density. Each specimen was affected from the environmental conditions. However, water affected all specimens more than the other environmental conditions, such as salty water, oil and braking liquid. With the increasing of temperature, the ingredients in the braking pad were affected other due to better diffusion. On the other hand, hardness of specimens increases and density decreases due to heat treatment and also specific wear ratio changes.Research limitations/implications – Limitations in the present research are as follows: two different pressures and eight different temperatures were used and brake linings were subjected to wear test, hardness tests, microstructures were examined.Practical implications – For future work, instead of buying expensive brake lining, new and cheaper ceramic linings are produced. By this process, economic benefit can be gained and also environmental protection can be succeeded in producing such asbestos free brake linings.Originality/value – This paper fulfills an identified information and offers practical help to the industrial firms working with brake lining and also to the academicians working on wear of materials.

This paper aims to research the tribological features of AISI 1035 steel, boronized at various parameters.

The samples were boronized via box boronizing method. By using Ekabor 2 powders, boronizing was conducted at 840, 880, 920, 960 and 1,000°C for two, four and six hours. Wear resistance of boronized samples at determined parameters were analysed. Wear experiments were conducted under 40 N constant load at pin‐on‐disk experiment setup. Also, microstructures and microhardness values of boronized samples were analysed to determine the most suitable boronizing parameters against wearing.

As a result of this study, the following findings are reported: it was determined as the temperature increased, the thicker the boride layer obtained during the boronizing. In the case of longer boronizing time, the distinct columnar structure was clearer. Whenever applying higher temperature and longer boronizing time, wear decreased and hardness values increased. It was also determined that when boronizing was conducted at 900 and 1,000°C for at least four to six hours, better results were obtained. Furthermore, the increment in the boronizing temperature and longer duration caused an increase in hardness from the surface to inwards and thus a decrease in wear ratio.

In the present study, only 40 N is used for a wear load and that is the limitation of the research.

Boronizing of the parts using 900 and 1,000°C temperature and four to six hours time, the better results can be obtained. Wear resistance can be improved in the determined temperature interval for boronizing process. Therefore, the industrial firms can be gained huge economical profits.

The outcome of the study will be beneficial for the academicians and industrial firms working on wear process. The service life of the steel parts can be extended via boronizing of steels working on quarries.

This study aims to present a direct repurposing activity of consumed high-speed steel (HSS) hacksaw blade into fine-looking handmade knives to increase the awareness about sustainability by evaluating the relationship between the quality of material alloys and heat treatment as well as cultural aspects such as the treatment on the HSS hacksaw blade that will affect the material hardness.

The quality of HSS hacksaw blade samples was analyzed by using scanning electron microscope/energy dispersive X-Ray spectroscopy (SEM/EDX) through the identification of material element’s properties. Besides, finite element structural analysis was performed by using SolidWorks Simulation to evaluate the material performance by determining the Von Mises stress to find the factor of safety of the knife designs. Then, the effect of tribology implementation toward mechanical properties of the handmade knives was determined by using a Rockwell C hardness test.

It is found that the material composition of carbon plays a vital role in increasing and improving the hardness and wear resistance of the HSS hacksaw blade. The Von Mises stress obtained is lower than the yield strength of 3,250 MPa by 71.44 per cent with the safety factor of 3.58,which means the design will not be subjected to failure. The mechanical properties of the HSS hacksaw blade such as hardness were determined averagely by 5 per cent of hardness increase.

It has been validated that the tribological effect toward the material characteristic leads to hardness changes which contributed to the enhancement of tool life of the HSS hacksaw blade, thus producing better quality knives.

This paper aims to understand the effect of the manufacturing process on the frictional and wear performance of polyamide.

Pin specimens were manufactured through injection moulding (IM) and selective laser sintering (SLS) manufacturing processes. The friction and wear performance was evaluated using a pin-on-disc configuration under dry and oil-lubricated conditions. The friction coefficient, wear resistance and surface temperature of specimens were measured, and failure morphology analysis was carried out to understand the mechanism.

SLS material exhibited significantly less friction, wear and surface temperature than IM material under dry conditions. Reduced ductility due to the sintering contributes to reduced friction, wear and heat generation. Under the dry condition, IM material exhibited plastic flow and roll-shaped deformation, whereas SLS material exhibited only local degradation due to its lesser ductility. Lubrication reduced friction and temperature for both SLS and IM materials. The porous nature of the sintered surface absorbed the lubricant and released it while sliding, which is confirmed by the brown-coloured wear track.

The study provides valuable input to the designers on the sliding contact performance of commonly adopted two different manufacturing processes of polymers; IM and SLS manufacturing.

Coating is a technique employed for the surface of materials to have thermal insulation, hot corrosion and oxidation resistance. Ion implantation forms modifications in surface composition or morphology of solids which yield to a change of physical and especially mechanical properties such as hardness and modulus of elasticity. The objective of this investigation is to concentrate on the friction and wear behaviour of TiN, N₂ and Zr implanted and TiN and Tinalox PVD coated 316L stainless steel and compare with a substrate. Mainly stainless steels were of attraction, because they frequently demonstrate a poor tribological behaviour, which can be enhanced when they are hardened by incorporating N₂, TiN Tinalox and Zr and forming a hardened surface zone.

The aim of the research is to increase piston and engine performance by using ceramic coated pistons instead of pistons which are manufactured from aluminum alloys and having a coated flame chamber.

Thermal torch and thermal shock tests were performed on the pistons and some specimens of 1.5 mm thick were prepared according to ASTM standards; both have the same material characteristics. In the present work, plasma spray technique was used for ceramic coating.

It was found that the ceramic coating, which, when performed properly, has compatible expansion coefficient with the aluminum alloy pistons, increases performance of pistons and engines.

Coatings were limited with one type of bonding and two ceramics, and coated parts were subjected to thermal torch and thermal shock tests.

For future work, instead of using other coating materials, stable yttria is used as the best coating material with optimum thermal resistance. By this process, working life of the machine parts can be extended and a number of economical advantages may also be obtained.

This paper fulfils the identified information and offers practical help to the industrial firms working with ceramic coatings and also to the academicians working on wear of materials.