船板表面花斑成因分析及改进措施

Cause Analysis and Improvement Measures of Surface Spots of Ship Steel Plate

为查找花斑缺陷形成机理,对带有典型花斑的钢板取样,对表面花斑部位进行光谱分析和扫描电镜分析,发现钢板表面富集Ni、Cu、As、Sb、Si等元素,同时富集Na、Mg、K、Ca等保护渣成分,上述元素的富集形成的除鳞难以去除的复合氧化铁皮是导致船板表面产生花斑的主要因素。通过减少钢中有害元素,提高钢质洁净度,降低钢中Si含量等措施,使船板表面花斑问题得到明显改善。

In order to investigate information mechanism of the fleck defects, the steel plate with typical fleck defects was sampled and the spectrum analysis and SEM analysis of the fleck site were made respectively. The results showed that the steel plate surface enriched Ni, Cu, As, Sb, Si and other elements, at the same time, enriched mould power compositions such as Na, Mg, K and Ca. The complex scales that form by the enriched elements and was difficult to remove by descaling are the main factors lead to forming flecks in ship steel plate surface. By reducing the harmful elements in steel, improving steel cleanliness, decreasing the Si content in steel and so on, ship plate surface fleck defects were markedly improved.