Optimization of hardness and wear parameters of Al-Cu-Si alloy using design of experiments

Abstract

Abstract Aluminium-Copper-Silicon (Al-Cu-Si) alloy of composition Al-1.5Cu-0.5Si alloy was successfully fabricated by sand casting process. Homogenization treatment was done at different temperatures to achieve uniform distribution of elements. The hardness was measured in different regions (outer, middle and inner) and the peak hardness of the alloy was obtained at 425 °C homogenization temperature in the outer region because of low solidification time at that region. L9 Orthogonal array was used to conduct the experiments and optimize the process parameters in the three regions for Specific Wear Rate (SWR) and the influencing parameters such as load, speed, homogenization temperature and sliding time were analyzed using Taguchi techniques. From the Analysis of variance (ANOVA), it was observed that for outer region, the sliding speed has the major effect on SWR followed by load, sliding time and homogenization temperature. In case of middle and inner regions, the influence of load on SWR was significant followed by sliding speed. The confirmation test was carried with obtained optimal process parameter. The surfaces wear mechanism behind Al-1.5Cu-0.5Si was analysed using scanning electron microscope (SEM) image