电渣重熔Mn18Cr18N钢的热变形行为与本构方程

Hot Deformation Behavior and the Flow Stress Equation of ESR Mn18Cr18N Steel

采用恒温热压缩实验方法,研究了电渣重熔Mn18Cr18N奥氏体不锈钢在变形温度950℃~1200℃、应变速率0.001~1 s^-1、真应变0.69变形条件下的热变形行为。分析获得了该钢具有较高的热变形激活能637.351 kJ/mol.热变形应变指数值4.95表明热变形主要受位错的攀移所控制。通过分析Z参数对流变应力曲线特征点的影响,建立了由Z参数表示的流变应力曲线特征点模型。基于此,建立了基于动态软化曲线特征点的两段式本构方程。

Hot deformation behavior of electro-slag re-melting Mn18 Cr18 N austenitic stainless steel has been studied in the temperature range of 950~1200℃and strain rate range of 0.001~1 s^-1 using isothermal hot compression tests.The hot deformation activation energy of the steel was calculated as high as 637.351 KJ/mol.The strain index of 4.95 suggests that hot deformation of the steel is mainly controlled by dislocation climb.The influence of Z parameters on the characteristic points of the flow stress curve was also studied.The relationships of the characteristic parameters with Z parameter were obtained.The flow stress equation of the steel was established using the two-stage equations based on characteristic points of the flow softening curves.