20CrNiMoH连铸坯表面裂纹成因及防止措施  

Crack Causes and Preventive Measures on Surface of 20CrNiMoH Steel Continuous Casting Slab

作　　者：陈庚[1,2] 方琴[1] 彭显平[1] 王泽忠[1] 王正云[2] 

机构地区：[1]四川工程职业技术学院材料工程系,四川德阳618000 [2]西华大学先进材料及能源研究中心,四川成都610039

出　　处：《热加工工艺》2017年第7期251-253,257,共4页Hot Working Technology

基　　金：四川省教育厅资助项目(16ZB0156)

摘　　要：某钢厂采用EAF-LF-VD-CC流程生产的20CrNiMoH齿轮钢出现裂纹,通过金相显微镜、扫描电镜、能谱分析等手段对裂纹成因进行分析。结果表明,连铸坯卷渣是导致裂纹产生的主要原因。通过增大钢水过热度、降低拉坯速度、控制结晶器内钢水液面波动幅度、调整浸入式水口插入深度和助熔剂成分等措施,使裂纹得到有效控制,产品质量得到提升。Cracks were found in the gear steel 20CrNiMoH produced by EAF-LF-VD-CC route in a steel-making plant, and the cracks causes were analyzed by metallurgical microscope, SEM and EDS. The results show that the slag entrapment of the continuous casting stab is the main cause of cracking. The cracks are controlled effectively and the product quality is improved by increasing the superheat of the liquid steel, reducing the casting speed, controlling the fluctuation range of the liquid steel in the mold, adjusting the depth of the submerged nozzle and the composition of the fluxing agent.

关 键 词：20CrNiMoH 表面裂纹 齿轮钢 连铸工艺 卷渣 

分 类 号：TG245[金属学及工艺—铸造] TF703[冶金工程—钢铁冶金]