Study on Constitutive Equation and Thermal Processing Map of Deformed TC4 Titanium Alloy under Hot Compression

In order to accurately obtain the deformation characteristics and suitable thermal deformation conditions of deformed TC4 titanium alloy and guide the design of deformation process parameters, the MMS-100 dynamic thermal simulator was used to conduct hot compression tests, the thermal deformation behavior of the deformed TC4 titanium alloy under the condition of strain rate of 0.01-10 s^-1, the deformation temperature of 880-1030℃was studied, and the constitutive equation of the deformed TC4 titanium alloy based on Arrhenius formula was derived, and the reliability of the constitutive equation was verified by Zerner-Hollomon parameters.The thermal processing map of deformed TC4 titanium alloy was established by using the dynamic materials model (DMM).The research results show that the flow stress of TC4 alloy decreases with the increase of deformation temperature and the decrease of strain rate.The coefficient of determination obtained by linear fitting of the steady-state stress and the compensation factor Z is 0.96, and the established constitutive model for thermal deformation can be used to describe the thermal deformation behavior of the deformed TC4 titanium alloy.The thermal processing safety zone of the deformed TC4 titanium alloy is the deformation temperature of 880-920℃, the strain rate of 0.01-0.15 s^-1 and the deformation temperature of 990-1030℃, the strain rate of 0.01-4 s^-1.