TA15合金电致动态球化动力学

Electro-induced Dynamic Globularization Kinetics of TA15 Alloy

摘要:

开展了脉冲电流辅助压缩试验，结合金相组织定量分析，对TA15钛合金片层组织的动态球化行为、规律、机制以及球化动力学曲线和模型进行了深入研究。结果表明，电流密度的增大将进一步加剧流动软化现象，球化率随着电流密度的增大和变形量的增大而提高。基于Avrami方程建立了TA15合金电致动态球化动力学模型，模型预测动态球化临界应变ε_c和完成动态球化应变ε_f的范围在0.090~0.187和5.02~6.31，且都随电流密度的增大而减小。球化动力学速率随着应变和电流密度的增大先增大后减小。此外，电流密度越大，球化动力学速率峰值越大，峰值对应的应变越小。

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.