Effect of TiB2 content on microstructure and mechanical properties of (TiB2p+B4Cp)/Al composites fabricated by microwave sintering

Abstract

This study demonstrates a novel method to improve the density, interface bonding strength and mechanical properties of the B4Cp/Al composites by directly adding TiB2 to the material. Specifically, the (TiB2p+B4Cp)/Al composites with different TiB2 contents were successfully fabricated by ball milling (BM) and microwave sintering (MS). The results indicate that the developed (TiB2p+B4Cp)/Al possess a clean interface, with the absence of any reaction, thus, confirming microwave sintering as one of the preferred ways to prepare the (TiB2p+B4Cp)/Al composites. On adding TiB2, the densification in the microstructure is noted to initially increase, followed by a decrease. Overall, the TiB2 and B4C particles are noted to synergistically improve the densification as well as ameliorate the interfaces and microstructure. As a result, the optimized composites exhibit the compactness and Vickers hardness as high as 94.6% and 153.42HV0.3 respectively. The highest value of the compressive strength is determined to be 578.71 MPa at 50.0%. Further, no macroscopic fracture is noted to occur after 50% compression strain.