Direct hcp→ bcc structural phase transition observed in titanium alloy at high pressure

摘要

Structural stability of Ti alloy, stabilized as a mixture of bcc (β) and hcp (α) phases, was investigated up to 71 GPa. Over this pressure, β phase remains stable, while for a phase, a decrease in cla ratio from 1.601 at ambient pressure to 1.568 at 36 GPa is observed, followed by an increase to 1.613 at 44 GPa. A steady value is then observed up to 67 GPa. Above 58 GPa, the authors also observe that a phase peak intensity is decreasing. At 67 GPa, the authors only observe β phase peaks, which indicates that α→β structural phase transition is complete.