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

Highlights: • Effect of Ti₃AlC₂ content is investigated for Ti₃AlC₂/TA15 composites. • TiC/Ti3AlC phase with quasi-continues network was formed by in-situ reaction. • The mechanical properties of Ti₃AlC/TiC/TA15 composites were enhanced significantly. • The main mechanism of crack self-healing is discussed. -- 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.