钢材及焊接热影响区中低周疲劳裂纹扩展的原位观察

In-Situ Observation upon Low Cyclic Fatigue Crack Extension in Steel and Heat Affecting Zone of Welding

在扫描电镜下对铁素体-珠光体钢及焊接热影响区的低周疲劳裂纹扩展进行了动态原位观察，材料的微观组织对裂纹的扩展存在着明显的影响。提出疲劳裂纹扩展的形态及方式与材料的疲劳裂纹扩展阻力之间存在着一定的关系，值得进一步研究。

In-situ observation upon the dynamic extension of low cyclic fatigue cracks in ferritepearlite steels and the heat affecting zone of welding under SEM was carried out. There was a definate effect of the materials microstructures on the behavior of crack extensions. A proposal was put forward that a certain correlation may exist between the growth morphology and pattern and the resistence of the material to the fatigue crack extension, which remains to be investigated further