材料期刊网

采用自约束热疲劳试验方法分别对H13、3Cr2W8V和1.2367钢进行热疲劳实验，对比分析表面裂纹形貌与截面裂纹深度，计算热疲劳损伤因子。利用Gleeble－3500对材料进行高温抗压实验，并对材料的组织进行SEM观察和EDS分析，研究热疲劳裂纹的萌生、扩展与材料强度和韧性的关系。研究表明：1.2367钢热疲劳后，表面裂纹十分均匀、细小，没有形成主裂纹，其热疲劳抗力高于H13钢和3Cr2W8V。1.2367较高的强度提高了材料热疲劳裂纹萌生的抗力，材料的热疲劳性能不仅取决于强度与硬度，也取决于良好的冲击韧性。

With the self-restricting test method, the thermal fatigue test of H13,3Cr2W8V and 1.2367 were carried out. The morphology of surface crack and microstructures of the hot die steel were also analyzed by SEM and EDS. Using Gleeble-3500 thermal simulation testing machine, high temperature compression tests were investigated in order to acquire the connection between strength toughness and the formation of crack. The result show that , after thermal fatigue test ,the cracks of 1.2367 were smaller and more homogeneous than H13 and 3Cr2W8V. Excellent strength improved thermal fatigue resisting force. The thermal fatigue property not only depend on the strength and hardness, but also rest with the toughness of the steel.