Microstructures and tensile properties of low-cost TiBw/Ti–6Al–4V composites by vacuum reactive hot pressing

Abstract

Coarse Ti–6Al–4V powder with particle size of 150–250 μm are the by-conduct of the processing of spherical fine powder, and usually considered as waste powder. In order to reduce carbon emission during recycle process and obtain titanium-based material with low cost and good mechanical properties, the TiBw/Ti–6Al–4V composites using coarse Ti–6Al–4V powder with a particle size of 150–250 μm were designed and successfully fabricated by vacuum reactive hot pressing (VRHP). The microstructures and tensile properties of low-cost TiBw/Ti–6Al–4V composites at room temperature and elevated temperatures were studied to optimize the content of TiBw. Besides, the strengthening mechanisms were analyzed based on the analysis of plastic deformation behavior and the fracture morphologies. The results showed that the composites reinforced by 1.0 vol% TiBw exhibited superior strength and ductility synergy, with a high tensile strength of 952 MPa and an elongation of 18.4% at room temperature, which are 24.3% and 145.3% higher than that of monolithic Ti–6Al–4V alloy, respectively. In addition, the 1.0 vol% TiBw/Ti–6Al–4V composites also showed excellent mechanical properties under high temperatures. This work shows that combining the network microstructure strategy with coarse spherical powder offers a pathway to design a low-cost titanium matrix composite with promising mechanical performance.