Elevated temperature mechanical properties and fracture behaviors of the bond zone of aluminum matrix composites (Al-12Si/ABOw) with Al-12Si alloys

Abstract

Aluminum borate whiskers reinforced Al-12Si composites with Al-12Si alloys were fabricated by squeeze casting. The mechanical properties and fracture behaviors of the bond zone between the composites and Al-12Si alloys were experimentally investigated in the test temperature range from 25 to 350°C. The tensile results indicated that the bonding state of the bond zone was poor at relative low test temperatures while was improved as temperature rising up to 350°C. Nano-indentation experiment was conducted at elevated temperature to evaluate the nano-hardness and Young's modulus of the materials. The calculation method of Young's modulus was discussed and the computation results support the relevant conclusions of tensile analysis. The temperatures were found to greatly influence the bond quality between the composites and Al-12Si alloys, which would cause a change of fracture position from the bond zone to the unreinforced Al-12Si alloys with elevated temperatures.