Influence of RHA reinforcements on mechanical and wear behavior of Al 4032 composites

This study was aimed at developing low-cost composites with high specific strength and better performance by incorporating agro-waste as reinforcements. The stir-casting technique was adopted for fabricating composites with aluminum (Al) 4032 as matrix material and 0, 2, 4 and 6 wt.% rice husk ash (RHA) as reinforcements. The mechanical properties of the produced composites were investigated, and the wear rate under dry conditions was also experimented on, to assess the characteristics of the produced composites. Energy-dispersive X-ray spectroscopy and scanning electron microscopy analyses were done to study the presence and distribution of reinforcements in the matrix material. The surface of specimens after wear test was analyzed from optical microscope images. The influence of process parameters such as reinforcement (wt.%), speed (revolutions per min (rpm)) and load (N) on wear rate was identified, and the parameters were optimized for minimum wear rate using a Taguchi L₁₆ orthogonal array. The percentage contribution of process parameters was obtained by performing analysis of variance. Better results were obtained for composites with 6 wt.% RHA with 84 HRB, 92.30 HV, ultimate tensile strength of 383.73 MPa and ultimate compressive strength of 571.6 MPa. Minimum wear rate was obtained for composites with 6 wt.% RHA at 100 rpm and 10 N. Speed was found to be the most contributing factor, with 72.94%, followed by load, with 13.34%, and weight percentage of reinforcements, with 11.88%.