Al6061 Reinforced Al2O3 Metal Matrix Composite Produced by Double Blade Stir Casting

Abstract

Demand for materials with excellent mechanical properties and lightweight increase in a recent year especially for high-performance applications. Aluminum reinforced Al2O3 composite (AMC) provide this superior property. Therefore in this research, aluminum alloy 6061 was used as a matrix and Al2O3 with 10 and 15 Vf-% as a reinforced for making metal matrix composites while magnesium as a wetting agent was used various from 8, 10 to 15 wt-% to improve the wettability between Al and Al2O3 since aluminum was poor wetting with ceramic. Al alloy 6061 was melted at 800 oC and magnesium was added into Al molten, then Al2O3 particles were poured into the melt. The process using double stirrer with a rotational speed of 1000 rpm for 3 minutes to distribute all Al2O3 particles in the Al melt and all the gas bubble formed was removed by flushing an Argon for 2 minutes. The composites produced then characterized both mechanical properties and microstructural analysis. The focus of this research is to investigate the effect of Al2O3 and Mg on the mechanical properties of composites. The result showed that the optimum tensile strength was 202 MPa which was obtained in composite with 10% Vf-% Al2O3 and 10 wt-% Mg. Moreover, hardness and wear resistant to composite increased with the addition of Al2O3 and Mg content due to good wetting in composites with 10 wt-% Mg. The double blade stirrer has contributed to the random distribution of Al2O3 particles in the molten Al. The microstructure observations showed that the composites yield pores and impaired the mechanical properties of composites.