CSP生产C-Mn钢薄带组织与表面裂纹研究  

Surface Crack Analysis and Microstructure of C-Mn Thin Slab Steel Produced by CSP

作　　者：张超[1,2] 宋畅[1] 韩斌[2] 谭佳梅[2] 郭茜[1] 吴润[1] 

机构地区：[1]武汉科技大学材料与冶金学院,湖北武汉430081 [2]武汉钢铁集团公司条材总厂CSP分厂和技术中心,湖北武汉430081

出　　处：《钢铁研究学报》2011年第5期50-54,共5页Journal of Iron and Steel Research

基　　金：湖北省自然科学基金资助项目(2008CDB256)

摘　　要：在武钢CSP生产线上,通过控轧控冷工艺生产低成本低碳C-Mn钢薄板。结果表明,生产出的薄板屈服强度大于313 MPa,抗拉强度高于400 MPa,伸长率超过37%,屈强比低于0.83,冷弯性能良好,满足塑性要求,但常出现表面裂纹。从热力学角度分析出尺寸大于83 nm的硬脆粒子会引起裂纹,而钢中析出物尺寸约为30 nm,不足以引起裂纹。金相和扫描电镜观察到裂纹周围有混晶现象,计算表明混晶造成的应力集中约为120 MPa,大于F3轧制时钢带的强度,容易导致裂纹的产生。经提高开轧温度、降低终轧温度及卷取温度后,表面裂纹发生率从3.67%降低到了1.34%。C-Mn thin slab steel had been produced at low cost by controlled rolling and cooling method in CSP factory of Wuhan Iron and Steel（Group） Corporation.The mechanical properties of tested steels were measured as： the yield strength of 313MPa,the tensile strength of ≥400 MPa and the elongation of ≥37%.The YR was below 0.83 and ductility was good.However,the surface cracks often appeared.The particles with size of 83 nm can cause cracks by thermodynamics analysis,while the particles in the experimental steel was about 30 nm,which cannot bring about cracks.Meanwhile,mixed-grain was observed in the vicinity of the crack.The stress concentration calculated to be 120 MPa,which was more than the strength of the steel rolled by F3 pass,may probably lead to crack.The rate of surfacial crack reduces from 3.67% to 1.34% with higher start rolling temperture as well as lower finishing rolling temperture and coiling temperature.

关 键 词：CSP 表面裂纹 热力学 混晶 

分 类 号：TG335.55[金属学及工艺—金属压力加工]