8Cr5MoV冷轧工作辊用钢的热变形行为

Hot deformation behavior of 8Cr5MoV steel for cold working roller

利用Gleeble-3500热模拟机在变形温度为850~1150℃、应变速率为0.005~5 s^-1、最大变形量为60%的条件下,对8Cr5MoV冷轧工作辊用钢进行热压缩试验。通过研究试验获得的真应力-真应变曲线,获得了该合金的热变形行为及热加工特征,并采用双曲正弦模型来描述8Cr5MoV合金钢的热变形行为,建立了该试验条件下材料的本构方程和热加工图。研究结果表明:Arrhenius模型可以较好地表征8Cr5MoV合金钢的热变形行为,在本试验条件下热变形激活能为393.6075 k J·mol^-1;在不同应变条件下,8Cr5MoV合金钢的热加工图有显著差异,与动态再结晶软化有关。在变形温度为1075~1150℃、应变速率为0.0183~1 s^-1时,能量耗散效率均在31%以上,能量耗散效率峰值可达38%,热加工性能最佳。

Thermal compression experiments of 8Cr5MoV steel for cold working roller were carried out by thermal simulation machine Gleeble-3500 under the deformation temperature of 850-1150℃,the strain rate of 0.005-5 s^-1 and the maximum deformation of 60%,its hot deformation behavior and the hot processing characteristics were obtained by the true stress-true strain curve coming from the experiments.Then,the hot deformation behavior of 8Cr5MoV alloy steel was described by the hyperbolic sine model,and the constitutive equation and hot processing map of the material under the experimental conditions were established.The results show that the Arrhenius model characterizes the hot deformation behavior of 8Cr5MoV alloy steel precisely,and the thermal deformation activation energy under this experiment condition is 393.6075 k J·mol^-1.Furthermore,the hot processing maps of 8Cr5MoV alloy steel have significant differences under the different strains,which is related to dynamic recrystallization softening,and the best hot processing performance with more than 31% energy dissipation efficiency and 38% peak value of energy dissipation efficiency was obtained under the deformation temperature of 1075-1150℃ and the strain rate of 0.0183-1 s^-1.