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In this paper, effect of secondary ageing process on the hardness and the abrasive wear resistance of AlSi10Mg casting alloys was studied. In the T6 temper heat treatment, AlSi10Mg alloy was aged at 170 °C for 4 hours. In secondary ageing process, AlSi10Mg alloy aged at 170 °C for 10 or 30 minutes was re-aged at 100 °C for 135 hours. Abrasive wear tests were performed on pin-on disk abrasive wear tester under 20 N and 30 N loads and 180 Mesh abrasive papers and at the sliding speed of 0.2 ms-1. Abrasive wear test results revealed that specimen aged at 170 °C for 30 minutes and then re-aged at 100 °C for 135 hours has the highest abrasive wear resistance. [ABSTRACT FROM AUTHOR]

In this study, the effect of CrN coating by physical vapour depositiom method on wear behaviour of AISI 3343 steel was studied. Wear tests were performed on pin-on-disc device under loads of 10 N, at linear sliding speed of 0,4 m/sec and sliding distances of 500 m, 750 m ve 1000 m. The experimental results show that specimens coated CrN have lower friction coefficient and wear rate than uncoated specimens. [ABSTRACT FROM AUTHOR]

In this study, the two-body abrasive wear behavior of aluminum matrix composites reinforced with silica particles has been investigated. The metal matrix composites were fabricated by a vacuum infiltration route. SiO2 particles with mean sizes of 120 and 80 μm are used as the reinforcement. 5 % magnesium was added into Al10Si alloys to promote wettability between metal matrix and reinforcement particles. Wear tests have been carried out on a pin on disc wear test apparatus under loads of 10, 20, 30 N, with 60, 100, 220 and 400 Mesh abrasive paper. Wear resistance of composites increased with increasing reinforcement particle size. Abrasion resistance decreased with increasing applied load and abrasive particle size. Dominant wear parameter is found to be the abrasive particle size in composites, whereas it is the applied load in matrix material. [ABSTRACT FROM AUTHOR]

In this study, effect of boronizing surface treatment on adhesive wear behavior of ferritic-pearlitic ductile iron was studied. Boronizing was performed in Ekabor II boronizing agent at 960 °C for 6 hours. Adhesive wear test was performed on pin on disc type wear tester under the load of 60 N, at sliding speed of 1 m/s for 3600 m, 7200 m ve 10800 m ve 21600 m sliding distance. Adhesive wear test results show that, wear resistance of boronized ductile iron is 50 times higher than those of ferritic-pearlitic ductile iron as-cast. [ABSTRACT FROM AUTHOR]

In this study, effect of counter gravity casting method on the adhesive wear behaviors of AlSi alloy was investigated. The counter gravity casting and gravity casting specimens were produced by pouring at 600, 640 and 690 °C, with 100, 250 and 500 mmHg vacuum level in sand mould. These specimens were tested on the modified pin on disk adhesive wear tester. Adhesive wear tests were performed on the under normal loads of 20 and 60 N, and sliding speed of 1 m/s. Adhesive wear test results showed that the specimens have similar wear trend with hardness results under low load (20N), but when the load increased (60N), the specimen with highest hardness exhibited the worst adhesive wear resistance. [ABSTRACT FROM AUTHOR]

In this study, wear behavior of B4C particle reinforced Al matrix composites produced by powder metallurgy technique has been investigated under dry sliding conditions. Characterization of composites were determined by microscopic examinations, hardness measurements and abrasive wear tests. Abrasive wear tests were conducted with 180 and 400 Mesh Al2O3 paper under 10 N and 20 N load 0,2 m s-1 sliding speed. Hardness increased by addition of B4C particles. While 20 % B4C particles reinforced composites have shown the highest hardness values, 10 % B4C particles reinforced composites have shown ultimate wear resistance. [ABSTRACT FROM AUTHOR]

In this study, the effect of the matrix structure on the dry sliding wear behaviour, friction coefficient and pin temperature of ductile irons was investigated. Wear tests were carried out at normal atmospheric conditions and room temperature on a pin on disc type tester at constant sliding speed (1ms-1) and sliding distance (3.6 km) under various sliding loads in a range of 20 to 60 N. The worn surfaces were examined by scanning electron microscopy (SEM). Wear rate of as-cast ferritic ductile irons increased with increasing test load, whilst that of as-cast pearlitic irons decreased. Tests revealed that, as-cast pearlitic ductile iron exhibited higher friction coefficient and friction temperature than as-cast ferritic ductile iron. The experimental results showed that the friction temperature increased with decreasing the friction coefficient of as-cast ferritic and pearlitic ductile irons. [ABSTRACT FROM AUTHOR]

In this study, the effect of the reinforcing particle size on the abrasive wear behaviour of Al-55vol.% SiC particulate (SiCp) reinforced composites produced by pressure infiltration technique has been investigated. Abrasive wear tests were carried out under the normal loads of 12, 24 and 36 N, against to 100, 280 and 500 mesh abrasive Al2O3 papers using a pin-on-disc type wear tester. The composites showed excellent wear resistance when compared to the unreinforced alloy. The wear rate of the composites increased with increasing applied load and abrasive grain size, Increase of reinforcement particle size improved the abrasion resistance of the composite. [ABSTRACT FROM AUTHOR]

In this study, the effects of reinforcement volume fractions on abrasive wear behavior were examined in Al–MgO reinforced metal matrix composites of 5%, 10% and 15% reinforcement – volume ratios produced by melt-stirring. Abrasive wear tests were carried out by 60, 80 and 100 mesh sized Al 2 O 3 abrasive papers and pin-on-disc wear test apparatus under 10, 20 and 30 N loads at 0.2 m/s sliding speed. The mechanical properties such as hardness and fracture strength were determined. Subsequent to the wear tests, the microstructures of worn surfaces were examined by scanning electron microscope analyses. While increased MgO reinforcement volume fraction in the composite resulted increased hardness, fracture strength was determined to decrease. Additionally, it was found that increased MgO reinforcement volume fraction in the composite was accompanied with increased wear loss and porosity as well as reinforcement – volume ratio was identified to be significant determinants of abrasive wear behavior. [ABSTRACT FROM AUTHOR]

Wire electrical discharge machining (WEDM) technology is a special electrothermal processing method that can precisely production of parts with variable stiffness with sharp edges or production of complex geometric parts which are difficult to produce by traditional manufacturing methods. It has an important place in production sector in terms of low energy consumption. In this study, the relationship between processing parameters on surface quality on the ferritic ductile cast iron (GGG-40) material in WEDM process with molybdenum wire was investigated by Response Surface Methodology (RSM). The aim of this study is to determine the optimum process parameters for low-cost production of GGG-40 material with sharp-edged and complex geometry parts using the WEDM method. In experimental works, surface roughness, and process time were investigated using table feedrate, pulse on time, and pulse space as cutting parameters. The surfaces obtained as a result of the experiments were evaluated in terms of surface quality with Scanning Electron Microscopy (SEM), and surface roughness device. According to the findings, it has been observed that the surface roughness has increased with increasing table feedrate, and pulse on time, and surface roughness decreased with pulse space increasing. Also, it is understood that pulse on time is the most important factor effecting surface quality. It has been found that the process time depends on only the table federate where they are inversely proportional. As result of RSM analysis, optimum cutting parameters were obtained in terms of lowest surface roughness, lowest process time and best time/performance condition on both parameters for ferritic ductile cast iron in WEDM process. [ABSTRACT FROM AUTHOR]

In this study, the effect of TiN coating by physical vapour deposition method on wear behaviour of austempered ductile iron was studied. For this purpose, austenitising at 900°C for 60 min and later austempering at 360 °C for 30 and 90 min was applied to the specimens. After heat treatment, the surfaces of these samples were coated TiN by PVD method. Wear tests were performed on pin-on-disc device under loads of 20 N, 40 N and 60 N, at linear sliding speed of 1m/sec and sliding distance of 1800 m. The experimental results show that pearlitic microstructure of ductile iron turned into ausferritic structure depending on heat treatment conditions. The wear of specimen was reduced 3-4 times by the effect of TiN coating. [ABSTRACT FROM AUTHOR]