文档介绍：第 13卷第 1期 2007年2月 宽厚板 WIDE AND HEAVY PLATE February 2007 ‘19‘ 技术讨论· Q460高性能钢表面裂纹的分析 蒋联民胡湘红 (舞钢钢铁有限责任公司) 摘 要 针对Q460/Z35高层建筑用钢板表面出现的裂纹缺陷,采用光学、电子扫描显微镜和INCa能谱仪 进行分析。结果表明,裂纹具有沿钢板纵向延伸、多分布在板尾、偏向板边且深度很小的规律性,对缺陷作定性 分析发现含氧量很高,多数裂纹中夹带细小、脆性较大的氧化物夹杂,裂纹根部三叉晶处富碳。产生缺陷的原因 是在不平衡冷却条件下形成的薄膜状富碳奥氏体及夹带的夹杂物,在热加工过程中因形变不均匀,造成局部表 面开裂。 关键词裂纹热加工形变 Analysis on the Surface Cracks of High Performance Q460/z35 Plate Jiang Lianrnin and Hu Xianghong (W uyang Iron and Steel ) Abstract Analysis on the surface cracks of Q460/Z35 plate for high rise building is carried out by using optical scanning microscope,electronic scanning microscope and INCa energy result shows that the cracking always propagates along the length of plate,mostly scatters over plate tail,locates more closer to plate sides and qualitative analysis on the cracking defects demonstrates that there are higher oxygen concentration and tiny oxide inclusions with higher brittleness entrapped among most cracks, rich carbon concentration in three pronged crystal structure at the root of defects are caused by the membrane type austenite of rich carbon concentration and entrapped inclusions formed under unbalanced cooling conditions. As a result of non——uniform deformation during hot forming,local surface cracking happens at last. Keywords Crack,Hot forming,Deformation 1 前言 与普