Characterization of (B4C+Ti) Hybrid Reinforced Mg and AZ91D Composites

Abstract

Ceramic hybrid particulate reinforced magnesium matrix composites have attracted much attention in recent years, owing to their light weight, high specific strength and stiffness, excellent wear and damping properties, and have very wide popularization and application prospects in the automotive and aerospace fields. A simple and novel technique, in situ reactive infiltration technique, was utilized to prepare (B4C+Ti) hybrid reinforced Mg and AZ91D composites. The microstructure, produced phases, wear, compression and bending performance were characterized and analyzed in depth. The results showed that extending the holding time for preparing the composites and magnesium alloy as the matrix were both beneficial for the generation of interpenetrating networks within the composites, which means more sufficient and complete in situ reactions between B4C and Ti particles. More sufficient and complete reactions facilitate stronger interfacial bonding, leading to an improvement of the wear, compression and bending performance of the composites. The wear mechanisms for both kinds of composites were abrasive and delamination wear. (B4C+Ti)/AZ91D composites exhibit better compression performance and this can be attributed to the microstructure of the composites and work-hardening and softening during compression.