采用光学显微镜、扫描电镜以及能谱分析等方法对低合金中厚板边部裂纹形成机制进行研究。结果表明:中厚板边部裂纹的形成是由于在轧制过程中钢板边部表层出现低温组织;变形不均匀导致边部应力集中,以钢板次表层存在的皮下气泡或颗粒状CaO-SiO2-Al2O3夹杂物为裂纹源,萌生裂纹并扩展,形成中厚板边部多处断续出现的横向应力裂纹。 The formation mechanism of the edge cracks in the low alloy plate was studied by optical microscopy, scanning electron microscopy and energy spectrum analysis. The results show that the formation of cracks in the edge of the plate is due to the low temperature microstructure of the edge of the plate during the rolling process. The non-uniform deformation leads to the stress concentration in the edge. The sub-surface bubbles or granular CaO-SiO2- Al2O3 inclusions as the source of cracks, initiation cracks and expansion, the formation of a number of intermittent edge of plate transverse fracture occurred intermittently.