冷轧深冲汽车板表面夹杂缺陷的研究

Research on Surface Inclusion in Deep-drawing Cold Rolled Sheet for Automobile

采用扫描电子显微镜和电子探针等设备,对冷轧深冲汽车板表面存在的两种不同形貌夹杂缺陷进行了观察分析;结果表明:两种不同形貌的夹杂缺陷的产生一部分主要是因为中间包钢液太少,液面形成漩涡导致覆盖剂卷入造成的。另一部分是由于冶炼过程中的脱氧产物未充分上浮,或者是连铸过程中未保护浇铸产生的二次氧化产物留在钢液中,在钢液凝固过程中低熔点的FeS、FeO由于钢液选分结晶,在晶粒边界及枝晶间析出,经过具有还原性气氛的连续退火炉高温段时被还原产生的。

Surface defect of two diversity pattern caused by inclusion in deep-drawing cold rolled sheet for automobile were observed and analyzed by scanning electronic microscope （SEM） and electronprobe microanalyzer （EPMA）. The results show that a part of two different feature inclusion defects is mainly caused by the tundish haing little of molten steel hence cover powder being involved in molten steel by cyclone; Tthe other inclusion defects are caused by the not fully ascents deoxidation products, and the other is caused by the secondary oxidation products of molten steel because continuous casting process is not protected. It is precipitates in the grain boundaries and inter-dendritic, after having reduction the atmosphere of the continuous annealing furnace is created to reduction.