DC51D+AZ热镀铝锌薄板弯曲成形时出现了弯曲折痕缺陷, 对正常产品和缺陷产品的化学成分、组织和性能进行对比分析以找出缺陷产生的原因。结果表明: 较低温度的终轧、卷取工艺导致薄板晶粒细化、硬度增高、屈服伸长率增大、塑性变形的稳定性变差是导致产生弯曲折痕缺陷的主要原因。建议钢板生产厂家生产DC51D+AZ热镀铝锌薄板时应采用较高温度的终轧、卷取工艺和充分的退火。

Bending creases appeared on the DC51D+AZ hot-dip Al-Zn alloy coating thin plate in the process of bending forming. Chemical composition, microstructure and mechanical properties of normal product were contracted with those of defective product in order to find the causes of the defects. The results show that lower ultimate rolling temperature and coiling temperature were the main reasons for the defects because they refined the grain size of the thin plate, increased the hardness and the yield elongation and reduced the stability of plastic deformation. Consequently, it is proposed that the manufacturer raise ultimate rolling temperature and coiling temperature and enough annealing to produce the DC51D+AZ hot-dip Al-Zn alloy coating thin plate.