New insights in the development of α phase during continuously heating in a β-quenched Ti-5321 alloy

Abstract An in-depth understanding of the development of α phase have been proposed in a β-quenched Ti-5Al-3Mo-3V-2Cr-2Zr-1Nb-1Fe alloy during continuously heating process. Acicular α, striated α and string-like α were displayed at different temperatures. The acicular α formed at 390 °C gathered together in parallel to form clusters, which originated from the assisted nucleation of ω clusters. The striated α formed at 570 °C showed highly strained lattice inside with unique satellite reflections, referring to the displacive-diffusion formation mechanism of α phase. The string-like α formed at 690 °C was the result of the impingement of individual α phase. These results provided new insights into the phase transformation mechanism in the near β titanium alloys.