柳钢冷轧板表面出现了不同程度的发黑现象。采用表面粗糙度分析、微观形貌分析、表面残留氧化物分析等方法，对冷轧板表面发黑的原因进行了分析。结果表明：冷轧板表面发黑的原因是冷轧板在酸洗过程中发生了水腐蚀，导致冷轧板表面生成了一层薄的铁的氧化物。采取相关措施降低冷轧板表面残留的Cl^-质量浓度后，冷轧板表面发黑程度明显减轻。

The cold-rolled strip surface of Liuzhou iron and steel Co., Ltd. appeared blackening phenomenon in varying degrees. The causes of surface blackening of cold-rolled strip were analyzed by means of surface roughness analysis, micro morphology analysis and surface residual oxide analysis. The results show that the reason for blackening of the cold-rolled strip surface was the water corrosion during the pickling process, which resulted in a thin layer of iron oxide on the cold-rolled strip surface. After taking relevant measures to reduced the residual Cl^- mass concentration on the cold-rolled strip surface, the blackening degree on the surface of the cold-rolled strip was obviously reduced.