消除7×××系铝合金表面“黑条子”缺陷的方法

Tackle key problem of eliminate black strip limitation on surface of 7××× aluminium alloy

在热轧包铝的7A04、7A09等7×××合金时,板材表面经常会出现"黑条子"缺陷。分析认为"黑条子"缺陷是氧化铝粉等粉尘及氧化铝粉与乳液反应生成的金属皂在铝板上的沉积物。采用热轧开坯使锭坯减薄可减少热轧干轧道次,减少氧化铝粉的产生,从而避免"黑条子"缺陷产生。

When hot wiling encased 7xxx series aluminium alloy, such as 7A04,7A09 and so on, there always black strip limitation appearance on the surface of aluminium plates. From the analyzing, we come to the conclusion that the black strip limitation is the precipitate of metallic soap exist on the surface of aluminium plates, which is the reaction product that is obtained by the reaction of aluminium oxide powder,oxide aluminium powder and the emulsion. The black strip limitation could be avoid through the methods of reduce the engender of the aluminium oxide powder, and reduce the frequency of hot roiling dry roiling path through reduce the thickness of ingots by hot roiling start ingot.