Fabrication and Evaluation of Mechanical Properties of MMC (Al+Al2O3+ZnO) through Powder Metallurgy

Aluminium matrix composites with Al2O3+ZnO reinforcements give superior mechanical & physical properties. Their applications in several demanding fields like automobile, aerospace, defence, sports, electronics, bio-medical and other industrial purposes are becoming essential for the last several decades. Various manufacturing processes e.g. stir casting, ultra-sonic assisted casting, compo-casting, powder metallurgy, liquid infiltration are being utilized for the production of the aluminium matrix composites. These composite materials possess improved physical and mechanical properties e.g. lower density, low coefficient of thermal expansion, addition of ZnO gives good corrosion resistance, high tensile strength, high stiffness, and high hardness and wear resistance. This paper reviews the characterization of mechanical properties with production routes of powder metallurgy for aluminium matrix- Al2O3+ZnO composites. Reinforcing aluminium matrix with much smaller particles, submicron or nano-sized range is one of the key factors in producing high-performance composites, which yields improved mechanical properties. A uniform distribution of the Al2O3+ZnO reinforcement phase in the Al matrix can be obtained by high-energy ball milling of Al+ Al2O3+ZnO blends. Increase in the hardness were obtained in the nano-composites as compared to the commercially pure aluminium. Ultrasonic assisted casting and powder metallurgy methods are becoming more common for the production of Al+ Al2O3+ZnO composites. Agglomeration of the reinforcing particles along with the increasing volume percentage is still a challenging task in composites materials manufacturing.