Enhancing Workability Through Adjusting Element Content: A Study on the Hot Deformation Behavior of a Modified Titanium Alloy

A modified near‐α titanium alloy of Ti‐5.2Al‐3.7Sn‐3.6Zr‐0.5Mo‐0.5Si‐0.02C is subjected to hot compression experiment using Gleeble‐3800 at deformation temperatures ( T ) from 940 °C to 1060 °C and strain rates ( ε ) from 0.01 to 1 s −1 . The β‐phase transus temperature of this alloy is decreased about 20 °C, which leads to lower deformation temperature. By fine‐tuning the contents of Al, Sn, Mo, Ta, and C elements, the machinability of alloy is optimized while maintaining its mechanical properties. According to stress–strain curves, an Arrhenius constitutive model for Ti‐5.2Al‐3.7Sn‐3.6Zr‐0.5Mo‐0.5Si‐0.02C alloy is established with a linear correlation coefficient ( R ) of 0.9868. The thermal mechanical processing map of the Ti‐5.2Al‐3.7Sn‐3.6Zr‐0.5Mo‐0.5Si‐0.02C alloy reveals its optimal processing parameters, ranging from 980 to 1010 °C, with a strain rate of 0.01 s − 1 . The instability region of the Ti‐5.2Al‐3.7Sn‐3.6Zr‐0.5Mo‐0.5Si‐0.02C alloy is reduced about 75% compared to that of the Ti60 alloy, and the energy dissipation rates within the processing regions remain at relatively high levels. Combined with the microstructure of the Ti‐5.2Al‐3.7Sn‐3.6Zr‐0.5Mo‐0.5Si‐0.02C alloy, the mechanism of microstructure evolution is discontinuous dynamic recrystallization with a large accumulation of dislocations near the high‐angle grain boundaries, which leads to the nucleation of grains occurred discontinuous dynamic recrystallization.