Microstructure and mechanical properties of Ta-Ti alloy by plasma-activated sintering

Tantalum-based alloys have developed rapidly in the fields of aerospace, nuclear industry, weapons, and national defense heavy industries due to their high melting point, low ductility-brittle transition temperature, and well ductility. However, pure tantalum exhibits low room-temperature strength and intergranular fracture, which is attributable to its strong adsorption to interstitial oxygen during sintering. In this work, high-strength Ta-Ti alloy is achieved by introducing Ti to consume oxygen by forming TiO2 and inhabiting the solution of oxygen in Ta alloys. The Ta-Ti alloys mainly consist of dense Ta matrix and dispersed TiO2 second phase. With the addition of 2 wt% Ti, the Ta-Ti alloy with high densification of 99.2% not only exhibits high ultimate bending strength of 1345 MPa from dispersion strengthening by TiO2 oxides, but also has good plasticity of 6% with a transgranular fracture and numerous dimple. The present work may facilitate the development and industrial application of Tabased alloys.

Automated summary

In this study, a high-strength Ta-Ti alloy was achieved by introducing Ti to consume oxygen, resulting in good plasticity and high ultimate bending strength. This research has important implications for the development and industrial application of tantalum-based alloys.