Microstructures, tensile properties and thermal stability of CuO coated aluminum borate whiskers reinforced 6061Al composite

Abstract

CuO coating on the surface of aluminum borate whiskers (ABOw) was prepared by hydrothermal synthesis. CuO coated ABOw reinforced 6061Al composite was fabricated by squeeze casting. The preparation process and characterizations of the CuO coated ABOw were investigated. The effects of CuO coating on the interfacial reactions between the whiskers and 6061Al matrix, and tensile properties of the composite in as-cast and after thermal exposure were investigated. The results show that a uniform CuO coating of ABOw is prepared by hydrothermal synthesis. CuO coating of the whiskers reacts with molten 6061Al during squeeze casting, increasing the wettability and tensile properties of as-cast composite. Meanwhile, MgAl2O4 uniformly forms at the interface, which can effectively reduce serious interfacial reactions between the whiskers and Mg in the 6061Al matrix at high temperatures, improving thermal stability of the composite.