Static and dynamic Hall-Petch relations in {332} 113 TWIP Ti-15Mo alloy

This study examined the effect of grain size on the tensile properties in {332} 113 113 twinning, which was not only due to the increased stress concentration from the interaction between the activated twins before the macroscopic yield and the grain boundary, but also a larger twin volume for macroscopic yield in the coarse-grained Ti-15Mo alloy. It gradually decreased with increasing strain, and negative values were obtained at strains above 0.23. The dynamic HallPetch relation was established by the effective grain size, which was similar at strains of up to 0.20 in Ti-15Mo alloy with static grain sizes of 29 mu m and 108 mu m. The decreasingly modified Hall-Petch coefficient was resulted from the successive occurrence of twinning activation, twinning suppression, and the twin-dislocation and dislocation-dislocation interactions.

Automated summary

This study investigated the effect of grain size on the tensile properties of Ti-15Mo alloy, revealing that the impact decreased with increasing strain and eventually became negative. A dynamic Hall-Petch relation was established based on effective grain size, showcasing twin activation, twin suppression, and various interactions.