40Cr钢的动态再结晶数学模型

Mathematical modeling for dynamic recrystallization behavior of 40Cr steel

利用单道次热压缩试验在Gleeble-1500热模拟试验机上,通过控制变形温度:973、1023、1073和1123 K,应变速率:0.01、0.1、1和5 s-1研究了40Cr钢的动态再结晶行为,根据应力应变曲线分析了40Cr钢的动态再结晶规律,采用回归法确定了双曲线本构方程中的材料常数和激活能(366.7 kJ/mol),建立了40Cr钢的本构方程;同时确定了40Cr钢的临界应变、峰值应变、峰值应力、稳态应力和动态软化量Ω等关键物理量。

Dynamical recrystallization behavior of 40Cr steel was investigated by means of single-pass compression tests on a Gleeble-1500 thermomechanical simulater at temperature of 973,1023,1073,1123 K and strain rate of 0.01,0.1,1 and 5 s-1.According to strain-stress curves,the material parameters in the hyperbolic sine constitutive equation for dynamical recrystallization of 40Cr steel were determined by regression method.The activation energy of dynamical recystallization of the steel is 366.7 kJ/mol,and the constitutive equation is established.At the same time,the key physical parameters of the steel such as critical strain peak strain and stress,steady-state stress,and dynamical softening amount Ω are obtained by linear regression.