Investigation on the Mechanical Performance of Silicon Carbide Reinforced Using Stir Cast and Grain Refined 6069 Matrix Composites

AA 6069 is a new entry to the family of 6000 series of heat treatable Mg-Si-Cu aluminum alloys. In this study 6069 matrix alloy is chosen due to high strength-to-weight ratio and widely used in space shuttle, military missile components, and automotive engines. Sic particles having average grain size of 20 μm with four volume fractions of 0, 5, 10 and 15% were incorporated into the alloy at the liquid state Stir casting followed by extrusion. Microstructure analysis was carried out using optical and electron microscope. It was found that yield strength and tensile strength of composites decreases with increasing the volume fraction of Sic particles, while hardness of the composites increases with increasing the volume fraction of the Sic particles.