中文摘要：

采用西北工业大学固体力学实验室研制的SHPB（split Hopkinson pressure bar）动态实验装置，测试了H13钢在20～600℃，应变率为10^3～10^4S^-1的流变应力和应变的关系，实验结果表明，应变速率和变形温度的变化强烈地影响H13钢的流变应力，流变应力随变形温度升高而降低，随应变速率提高而增大，在高温下出现明显的动态软化。根据得到的流变应力曲线，拟合出了Johnson-Cook模型中的相关参数。经与实验对比验证，Johnson-Cook本构模型能够很好地描述H13钢的动态力学性能，为工程应用中进一步的力学数值分析提供了重要的材料参数。

英文摘要：

To determine the true flow stress true strain relationship for H13 hardened steel, specimens were first tested from a strain--rate of 1000s^-1 to 10 000s^-1 and from room temperature to 600℃ at intervals of 200℃ with a split Hopkinson pressure bar apparatus in the solid mechanics laboratory of Northwestern Polytechnic University. The results show that the flow stress is influenced by both strain rate and deformation temperature, and the flow stress decreases with the increase of temperature. The parameters for a Johnson Cook constitutive equation were determined from the test results. The comparison between data of experimental and fitted constitutive equation indicates that the constitutive equation is suitable for expressing the dynamic behavior of H13 steel, which provides important material characteristic parameter for mechanics numerical analysis further in the project application.