The effect of hot oscillatory pressing sintering time on microstructure, grain growth kinetics and properties of W–Ti refractory alloy targets

The effects of different sintering times (0.5, 1 and 1.5 h) of hot oscillatory pressing on microstructure, densification, grain growth process and properties of 90W–10Ti refractory alloy targets are investigated for the first time in this work. With prolonged sintering time, both microstructure and relative density are markedly enhanced, accompanied by gradual abnormal grain growth. At a sintering time of 1.5 h, the highest density can reach 97.7%, and the grain size is about 2.14 μm. Due to the optimization and improvement of W-W particle adjacency and Ti-rich phase aggregation, its Vickers hardness and electrochemical corrosion current density can reach ∼526.41 HV 30 and 9.63 × 10 −6 A/cm 2 , with a significant improvement in alloy properties compared to those obtained with shorter sintering times. When the sintering time is short (0.5 and 1 h), its densification rate is faster, and the goal of rapid densification can be achieved in a short time. Moreover, the reduced number of microstructural defects leads to improved performance. Additionally, the grain growth exponent n was 2, indicating that the grain growth mechanism was grain boundary diffusion. Long sintering time caused grain growth, which had an adverse effect on its performance.