中文摘要：

对冷锻模具材料高速基体钢进行了室温下的单轴静态拉伸试验和应变控制单轴对称拉压低周疲劳试验,获得了静态拉伸力学性能和低周疲劳性能参数.通过对试验数据进行拟合,得到了高速基体钢材料在室温下静态单调拉伸应力-应变关系、循环应力-应变关系以及循环应变-寿命曲线.试验结果表明,该模具材料在本试验控制的循环应变幅范围内发生了循环软化,疲劳断裂之前未观察到明显的应力饱和现象.以控制应变幅为1.5%的试样为例,对材料的低周疲劳行为特性进行了分析.材料的循环应力响应分为明显软化,软化效应减弱和瞬时断裂3个阶段.

英文摘要：

Static uniaxial tension experiment and strain-controlled tension-compression fatigue experiments were conducted at room temperature to cold forging tool material,a matrix-type high speed steel.Mechanical property parameters under static tension and low cycle fatigue loading conditions were acquired through the experiments.Static monotonic tension strain-stress relationship,cyclic strain-stress relationship and cyclic strain-life relationship of the steel at room temperature were derived from regression of the experiment data.The experimental results show that cyclic softening happens to the tool material at all levels of controlled cyclic strain amplitudes in this study.No visible stress saturation is observed before fatigue failure occurrs.A specimen at the controlled strain amplitude of 1.5% was used as an example to investigate the LCF behavior characteristics of this material.The cyclic stress response shows a variation with three stages： the obvious softening stage,the slow softening stage and the final rupture stage.