51CrV4弹簧钢的高温塑性变形行为及本构模型研究

Research on High Temperature Plastic Deformation Behavior and Flow Stress Model of 51CrV4 Spring Steel

采用Gleeble-3800热模拟机对51CrV4弹簧钢进行热压缩变形试验。研究了变形温度和变形速率对材料流变应力演变规律的影响,建立了高温热压缩本构模型。结果表明:51CrV4钢热压缩变形过程中峰值流变应力随变形温度的增大而减小,随变形速率的增大而增大;51CrV4钢在变形温度1000℃,变形速率0.1 s^(-1)条件下会发生动态再结晶;建立了变形抗力随变形量、变形温度和变形速率变化的模型,该模型预测的流变应力与试验值基本吻合。

Gleeble-3800 thermal simulator was used to conduct the hot compression deformation tests for 51CrV4 spring steel.The effects of deformation temperature and strain rate on the evolution of flow stress were studied,and a high-temperature hot compression constitutive model was established.The results show that the peak flow stress decreases with the increase of deformation temperature,and increases with the increase of strain rate during the hot compression deformation;dynamic recrystallization phenomenon occurs in 51CrV4 steel under the conditions of 1000℃deformation temperature and 0.1 s^(-1) deformation rate;a constitutive model considering strain,deformation temperature and strain rate is established,and the flow stress predicted by the model is consistent with the experimental data.