Copper alloyed with various compositions of nickel and tin were cast into molds under argon atmosphere.The cast rods were homogenized,solution heat treated,followed by aging for different time duration.The specimens w...Copper alloyed with various compositions of nickel and tin were cast into molds under argon atmosphere.The cast rods were homogenized,solution heat treated,followed by aging for different time duration.The specimens were characterized for microstructure and tested for microhardness and wear rate.A hybrid model with a linear function and radial basis function was developed to analyze the influence of nickel,tin,and aging time on the microhardness and tribological behavior of copper-nickel-sin alloy system.The results indicate that increase in the composition of nickel and tin increases the microhardness and decreases the wear rate of the alloy.The increase in the concentration of nickel and tin decreases the peak aging time of the alloy system.展开更多
Zinc-aluminum alloys have been used as bearing materials in the past. In recent years, binary Al-Zn alloys and Al-Zn-Cu alloys are being used as an alternative to the Zn-Al alloys for bearing applications. In this stu...Zinc-aluminum alloys have been used as bearing materials in the past. In recent years, binary Al-Zn alloys and Al-Zn-Cu alloys are being used as an alternative to the Zn-Al alloys for bearing applications. In this study, both binary Al-25 Zn and Al-3 Cu were prepared using stir casting process. Homogenization of the as-cast alloys was performed at 350oC for 8 h and then, the alloys were furnace-cooled to 50oC. The homogenization led to the removal of the dendritic structure of the as-cast alloys. After homogenization, wear parameters optimization was carried out using Taguchi technique. For this purpose, L9 orthogonal array was selected, and the control parameters selected are load, velocity, and sliding distance. The optimum parametric condition was obtained using signal-to-noise(S/N) ratio analysis, and specific wear rate(SWR) is the selected response. The "smaller-the-better" is the goal of the experiment for S/N ratio analysis. After the optimization, confirmation tests were carried out using analysis of variance(ANOVA) from the developed regression equation. Finally, wear mechanism studies were conducted using scanning electron microscopy(SEM) and energy-dispersive X-ray spectroscopy(EDX) images.展开更多
文摘Copper alloyed with various compositions of nickel and tin were cast into molds under argon atmosphere.The cast rods were homogenized,solution heat treated,followed by aging for different time duration.The specimens were characterized for microstructure and tested for microhardness and wear rate.A hybrid model with a linear function and radial basis function was developed to analyze the influence of nickel,tin,and aging time on the microhardness and tribological behavior of copper-nickel-sin alloy system.The results indicate that increase in the composition of nickel and tin increases the microhardness and decreases the wear rate of the alloy.The increase in the concentration of nickel and tin decreases the peak aging time of the alloy system.
文摘Zinc-aluminum alloys have been used as bearing materials in the past. In recent years, binary Al-Zn alloys and Al-Zn-Cu alloys are being used as an alternative to the Zn-Al alloys for bearing applications. In this study, both binary Al-25 Zn and Al-3 Cu were prepared using stir casting process. Homogenization of the as-cast alloys was performed at 350oC for 8 h and then, the alloys were furnace-cooled to 50oC. The homogenization led to the removal of the dendritic structure of the as-cast alloys. After homogenization, wear parameters optimization was carried out using Taguchi technique. For this purpose, L9 orthogonal array was selected, and the control parameters selected are load, velocity, and sliding distance. The optimum parametric condition was obtained using signal-to-noise(S/N) ratio analysis, and specific wear rate(SWR) is the selected response. The "smaller-the-better" is the goal of the experiment for S/N ratio analysis. After the optimization, confirmation tests were carried out using analysis of variance(ANOVA) from the developed regression equation. Finally, wear mechanism studies were conducted using scanning electron microscopy(SEM) and energy-dispersive X-ray spectroscopy(EDX) images.