25mm7A09厚板心部裂纹成因分析

Analysis on Reasons of Center Cracks for 7A09 Plates of 25mm Thickness

25 m m7A0 9厚板边部区域沿厚度方向中心部位产生小裂口 ,小裂口的产生非铸锭冶金缺陷引起的。这是由于 轧制初期板材心部存在低塑性铸态组织 ,在此情况下板材进行滚边处理 ,滚边量过大导致板材边部出现内部开裂。为了消除此类小裂口 ,热轧时应控制铸锭加热温度 。

The small cracks in the center of 7A09 plates along the direction of thickness are due to the low plastic casting structure existed in the center of plates during early rolling. In the case,if the plates are edging rolled,center cracks at the edgc of plates will occur.In order to eliminate such small cracks, the heating temperature should be controlled during hot rolling,reduction in pass should be assigned appropriately.The edging in rolling should also be controlled at the same time.