Electro-induced Dynamic Globularization Kinetics of TA15 Alloy

Abstract:

The dynamic globularization behavior, law, mechanism, globularization kinetic curve and model of TA15 titanium alloy lamellar structure were studied by pulse current assisted compression test and quantitative analysis of metallographic structure. The results indicate that the increase in current density further aggravates the flow softening phenomenon. The globularization rate increases with the increase in current density and deformation. Based on the Avrami equation, a dynamic electro-induced globularization kinetics model for TA15 alloy is established. The model predicts that the ranges of the critical strain ε_c for dynamic spheroidization and the strain ε_f for completing dynamic spheroidization are 0.090–0.187 and 5.02–6.31, respectively, and both decrease with the increase in current density. The globularization kinetics rate increases first and then decreases with the increase in strain and current density. In addition, the higher the current density, the greater the peak value of the spheroidization kinetics rate and the smaller the strain corresponding to the peak value.