热轧板冷弯开裂分析

采用扫描电子显微镜和光学显微镜观察了热轧板在冷弯过程中开裂试样的断口形貌并进行了成分分析。发现裂纹内存在氧化铁且呈断续分布，裂纹两侧基体内存在着内氧化颗粒且其显微组织也有差异。分析表明，热轧板冷弯开裂是由热轧折叠缺陷造成的，但不影响整批材料的性能。实际使用中只要切除缺陷部位，即可正常使用。

CRACKING ANALYSIS ON THE HOT-ROLLED PLATE EXPERIENCING COLD-BENDING

A hot-rolled plate cracked during cold bending process. Scanning Electron Microscope and Optical Microscope were used to investigate the cracked plate. It is found that the oxide of Fe existed continually in the crack, and on both sides of the crack, inner oxidation occurred and the microstructure was obviously different. It is concluded that the fold defect produced in the hot-rolling process is responsible for the plate cracking, which would not affect the mechanical properties of the material. The hot-rolled plate would be in common use if the part of the fold defect were cut off.