热轧带钢表面边部与中部氧化铁皮颜色差异探究

针对邯宝热轧厂热轧卷开卷后边部表面氧化铁皮呈蓝黑色，中部表面氧化铁皮呈灰白色，用户把这种氧化铁皮颜色差异与产品的力学性能差异相关联的问题，分析了热轧钢卷边部与中部氧化铁皮颜色差异的根本原因，即钢卷边部与中部层间缝隙大小和降温速率存在差异，导致热轧钢卷表面氧化铁皮结构不同。为此，提出了减小带钢凸度、杜绝带钢边部厚度突降、适当增加卷取张力、保证带钢均匀降温等措施，有效改善了带钢表面氧化铁皮颜色差异现象。

Study on color difference of oxide between edge and middle surface of hot rolled coil

In view of the problems of blue-black oxide on the edge and gray oxide on the middle surface of hot rolled strip,and some users relate the difference of the oxide color to the mechanical properties of the product,the causes of oxide colour difference at edge and middle of strip were analyzed,which there were difference of coil interlayer gap size and cooling rate between edge and middle of strip and resulting in different oxide structure.Therefore,some measures were put forward,such as reducing strip crown,avoiding edge thinkness drop,appropritately increasing coiling tension and ensuring strip evenly cooling,which could be effectively improve the oxide color difference of strip.