采用扫描电镜形貌观察配合能谱仪成分分析及组织评级方法,经过分析,得到层状断口的微观形貌、组织和成分特征。结果表明,层状断口与板材的带状组织有关,带状组织有铁素体和珠光体条带,另外还包括贝氏体、粗大的链状碳化物等异常组织。相邻带状组织因其力学性能上的差异,致使拉伸过程中形变不能协调,塑性差的组织条带因其形变滞后,早期发生断裂,出现微裂纹,裂纹沿着两组织界面扩展,逐渐发展成为层状形态。 The morphological, microstructural and compositional characteristics of the layered fracture were analyzed by scanning electron microscopy (SEM) morphology analysis and compositional analysis with the grading method. The results show that the laminar fracture is related to the banded structure of the plate. The banded structure is composed of ferrite and pearlite bands. In addition, it also includes bainite and coarse chain carbide. Due to the differences of their mechanical properties, the adjacent bands can not coordinate the deformation during the stretching process. Because of the deformation delay, the early microstructures and fractures of the microstructures show the appearance of microcracks. The cracks propagate along the interfaces of the two tissues gradually Development into a layered form.