灯罩坯件开裂分析

Fracture Analysis on Semi-products of Lamp Chimney

分析了灯罩用薄钢板在冲压过程中发生开裂的原因,采用金相显微镜、扫描电镜和能谱仪对开裂样品的微观组织和夹杂物进行了分析,发现材料内部存在着硫化锰夹杂物,在薄钢板的冲压过程中,这些聚集的夹杂物在平面双向拉伸应力的作用下,形成微裂源和低应力破坏,导致了灯罩坯件的开裂失效。

The cracking of semi-products of lamp chimneys made of thin steel sheets during punch process was analyzed in this paper. Metallographic microscope, SEM and EDX were used to investigate the microstructure,the distributions and the compositions of non-metallic inclusions. The sulfured manganese inclusions were found in the steel sheets ,it was likely to cause cracking under plain tensile stress conditions when the steel sheets were punched, thus leading to the failure of the semi-products of lamp-chimney.