Effects of heat-treatment on interfacial microstructures and tensile properties of ZnAl2O4 and ZnO coated Al18B4O33w/Al composites

The pure aluminum matrix composites reinforced by ZnAl2O4 and ZnO coated aluminum borate whiskers were separately fabricated by squeeze casting. The effects of heat-treatment on the interfacial microstructures and tensile properties were investigated. The results show that interfacial products ZnAl2O4 and γ-Al2O3 do not react with aluminum matrix during heat-treatment at 520 °C from 1 h to 6 h and the interfacial microstructures do not change. The ultimate tensile strength and 0.2% proof stress increases but elongation to fracture of the composite ABOw/ZnAl2O4/Al declines after heat-treatment. However, tensile properties of the composite ABOw/ZnO/Al decline after heat-treatment.