Effect of microstructure on the mechanical properties of Ti-5Al-5Mo-5V-1Cr-1Fe alloy

Systematic investigation of microstructure on the dynamic behavior of titanium alloys are seldom reported in the literature. In order to further understand this topic, four types of heat treatment and hot processing are designed, resulting in the following microstructures: e.g., bimodal structure, equiaxed structure, basketweave structure and Widmanstatten structure. The mechanical response of Ti-5Al-5Mo-5V-1Cr-1Fe (Ti-55511) is characterized over a wide range of strain rates and temperatures. The findings of this experimental demonstrate that Ti-55511 alloy is a strain rate and temperature sensitive material. The results also show that the Johnson-Cook constitutive equation can be utilized to predict the dynamic behavior of Ti-55511 alloy. Moreover, adiabatic shear susceptibility is affected by microstructure type and tested temperature. Microstructural observation of the samples deformed at high strain rates indicate that the formation of the adiabatic shear band is highly influenced by the microstructure type, and shear failure is the main failure mechanism. To fully utilize the potential of the material, engineers can choose the optimal microstructure to fabricate components according to the service requirements.