通过微观形貌和成分分析研究了低碳铝镇静钢经氮氢罩式炉退火处理后冷轧钢板表面出现的丝斑缺陷。结果表明,无丝斑缺陷的钢板表面均匀光亮,钢板表层无异常的碳元素富集;有丝斑缺陷的钢板表面明显发黑、呈丝带状,缺陷部位呈岛状或线状,异常元素是石墨碳,在钢板表层一定深度范围内碳元素含量明显高于钢板基体。 The microstructure and composition analysis of the surface defects of the cold-rolled steel plate after the low carbon aluminum killed steel was annealed by the nitrogen-hydrogen shroud furnace was studied. The results showed that the surface of the steel without fusiform defects was uniform and bright, and there was no abnormal carbon enrichment in the surface of the steel. The surface of the steel with fusiform defects was obviously black and ribbon-shaped. The defects were islands or linear. The abnormal elements were Graphite carbon, the surface of the steel sheet within a certain depth of carbon content was significantly higher than the steel substrate.