采用光学显微镜、扫描电镜分析了高强钢板切割裂纹的组织形貌,应用X射线测定了钢板的残余应力。结果表明:切割后裂纹沿钢切割边部向基体进行延伸,裂纹宽度由前端向基体逐渐缩小。在边部形成组织粗大的低塑性区,从切割边向内组织类似于热影响区组织的变化特征。钢板上均存在不同程度的压应力,是造成延迟裂纹的重要原因。 The microstructures of cutting cracks of high strength steel were analyzed by optical microscope and scanning electron microscope. The residual stress of steel was measured by X-ray. The results show that the crack propagates along the cutting edge of the steel to the base after cutting, and the crack width gradually decreases from the front end to the base. In the edge of the formation of coarse coarse plastic zone, from the cutting edge inward tissue similar to the heat-affected zone tissue changes. There are different degrees of compressive stress on the steel, which is an important reason for delayed cracking.