电池壳钢夹杂物分析及冲压开裂缺陷解决措施

Analysis of inclusions in battery case steel and measures to solve stamping crack defects

电池壳钢中夹杂物是影响其深冲性能的重要因素。对某厂电池壳钢铸坯和冷轧板不同部位分别进行取样,并且对有砂眼缺陷的电池壳外壳样品进行取样,采用金相显微镜(OM)、扫描电镜(SEM)等表征方法分析电池壳钢洁净度水平并寻找电池壳钢砂眼质量缺陷的成因。研究结果显示,电池壳钢铸坯中夹杂物平均尺寸最大、密度最高的部位为内弧1/4处。冷轧板中夹杂物平均尺寸最大的部位是中心处,同时也是密度最低的部位。与其他六厂电池壳钢相比,该样品中夹杂物尺寸偏大,是导致与其他厂产品差距的主要原因。通过研究发现,不合理的脱硫工艺是导致电池壳钢冲压开裂缺陷的主要原因,通过将生产工艺优化为铁水预处理并经转炉直上后,产品未出现显著开裂问题。

The cleanliness of battery case steel is an important factor affecting the deep drawing performance.Characterization methods such as metallographic microscopy(OM)and scanning electron microscopy(SEM)were used to sample different parts of the slab and cold rolled plate of a certain factory s battery case steel,and samples of battery cases with sand hole defects were taken to analyze the cleanliness level of battery case steel and identify the causes of quality defects in battery case steel sand holes.The results show that the part which has the largest and densest inclusions in the battery case steel slab is the inner arc 1/4.The part which has the largest size of inclusions in the cold rolled plate is the center,and it also has the lowest density of inclusions.Compared with the battery case steel of other six factories,the larger size of inclusions in this sample is the main reason for the difference from other factory products.Through research,the unreasonable desulphurization process is the main reason for the cracking defects of the battery case steel.After optimizing the production process to pretreat the hot metal and direct casting after converter smelting,the product has no significant cracking problem.