Preparation and mechanical properties of titanium alloy matrix composites reinforced by Ti3AlC and TiC ceramic particulates

Abstract

Ti3AlC2 MAX phase ceramic particles were used to reinforce Ti-6.5Al-2Zr-1Mo-1 V (TA15) alloy. The composites with a network architecture were prepared by low-energy ball milling (LEBM) and spark plasma sintering techniques. The effects of Ti3AlC2 content (0.5–2.0 wt%) on the microstructure, mechanical properties and wear resistance of the composites was investigated. Experimental results showed that Ti3AlC2 particles were uniformly adhered to the surface of the spherical TA15 powders after the LEBM process. The Ti3AlC2 MAX phase was reacted with the TA15 matrix and in-situ generated Ti3AlC and TiC phases after the SPS processing. The reinforcements were distributed around the interface of TA15 matrix in a 3D network architecture. The hardness, tensile strength and compressive strength of the Ti3AlC/TiC/TA15 composites were enhanced significantly without much loss of ductility. Superior mechanical properties (tensile yield strength of 958 MPa and compressive yield strength of 1271 MPa), acceptable ductility (8.56%) and Vickers microhardness (369.7 HV) were achieved in the 1.0 wt% Ti3AlC2/TA15 composites with the quasi-continues network microstructure. The wear resistance of the Ti3AlC/TiC/TA15 composites was improved due to the high hardness and high strength as well as the self-lubricating of the MAX phase.