35CrMoV钢高温塑性变形行为及其本构方程建立

为了研究35CrMoV钢的高温变形行为,借助Gleelble 3800型热模拟试验机,在应变速率为0.01~10 s^-1、变形温度为950~1150℃的条件下进行轴向单道次高温压缩试验,并根据试验结果绘制35CrMoV钢的流动应力-应变曲线。分析研究了变形温度、应变速率对流动应力的影响,计算了变形激活能Q及参数n、A、α的取值。试验结果表明:35CrMoV钢在950~1150℃进行压缩试验时,存在动态再结晶和动态回复两种流动应力-应变关系,当应变速率为0.01和0.1 s^-1时,其流动应力-应变曲线主要表现为动态再结晶型;当应变速率为1和10 s^-1时,其流动应力-应变曲线主要表现为动态回复型。在试验条件下获得35CrMoV钢的平均变形激活能Q为310.433 kJ·mol^-1,建立了用于描述35CrMoV钢流动应力、应变速率和变形温度三者之间关系的本构方程。

High temperature plastic deformation behavior and constitutive equation establishment of 35CrMoV steel

In order to study the high temperature plastic deformation behavior of 35CrMoV steel,the axial single pass high temperature compression test was conducted by thermal simulator Gleelble 3800 at the strain rates of 0. 01-10 s^-1 and the deformation temperatures of 950-1150 ℃,and the rheological stress-strain curves of 35CrMoV steel were drawn according to test results. Then,the influences of deformation temperature and strain rate on the rheological stress were studied,and the deformation activation energy Q and the parameters of n,A and α were calculated. The test results show that when 35CrMoV steel is subjected to compression test at 950-1150 ℃,there are two kinds of rheological stress-strain relationships for dynamic recrystallization and dynamic recovery. When the strain rates are 0. 01 and 0. 1 s^-1,the rheological stress-strain curvess are mainly of dynamic recrystallization type,and when the strain rates are 1 and 10 s^-1,the rheological stress-strain curves are mainly of dynamic recovery type. In addition,under the test conditions,the average deformation activation energy Q of 35CrMoV steel is 310. 433 kJ·mol^-1,and the constitutive equation is established to describe the relationship among rheological stress,strain rate and deformation temperature of 35CrMoV steel.