Flow softening behavior of Ti-13V-11Cr-3Al beta Ti alloy in double-hit hot compression tests

Single-and double-hit hot compression tests were performed at 1030 degrees C and strain rate of 0.1 s(-1) on Ti-13V-11Cr-3Al beta Ti alloy to investigate the flow behavior and mechanism of microstructural evolution during the interpass period. It was observed that the flow stress level and the extent of yield point phenomena (YPP) were increased by an increase in the grain size. After the first pass, the microstructure was bimodal of large deformed grains and small recrystallized grains formed by continuous dynamic recrystallization. The increase in the interpass time to 100 s, led to the decrease in the yield drop and extent of YPP. However, the further increase in the interpass time to 300 s would result in an inverse effect. A combination between static recrystallization and metadynamic recrystallization was found responsible for grain refinement in the samples subjected to the interpass times below 100 s. At longer interpass times, i.e., 300 s, grain growth increased the average grain size.