Fabrication and Characterization of Rice Husk Ash Reinforced Aluminium Matrix Composite

Abstract

Aluminium matrix composites (AMCs) are renowned for their exceptional properties, including low density, high specific strength, high thermal conductivity, and abrasion resistance, making them ideal for advanced structural, automotive, and aerospace applications. However, the challenge of finding cost-effective and environmentally friendly reinforcement materials remains. Rice Husk Ash (RHA), an often-discarded by-product of rice milling, presents a viable solution. Its utilization in AMCs repurposes waste, reduces environmental impact, and offers an economically viable alternative to conventional reinforcements. This paper explores the use of RHA as a reinforcement in aluminium matrix composites, with varying concentrations of 3%, 6%, and 9% by weight prepared through sand casting. Tensile, compressive, impact, and hardness tests were conducted, and it was found that increasing the RHA content enhances the mechanical properties of the composites. Specifically, tensile strength increases by 10.57%, 16.83%, and 46.26%, and compressive strength by 17.17%, 27.81%, and 40.45% for 3%, 6%, and 9% RHA reinforcement, respectively, compared to base samples (pure aluminium). Significant improvements in Rockwell hardness and impact energy absorption were observed, with a maximum increase of 55.26% and 70.63% for the 9% RHA reinforcement. This study demonstrates the potential of RHA-reinforced AMCs to surpass the mechanical properties of pure aluminium, contributing to the circular economy by transforming rice husk waste into a valuable composite material for diverse structural applications.