摘要
针对生产中316LN钢出现的表面裂纹,采用宏观检验、微观检验及化学成分分析等手段对316LN钢中厚板表面裂纹产生的原因进行分析。结果表明:裂纹的形成可能是轧制前铸坯表面存在的凸起导致的。利用ANSYS/LS-DYNA有限元软件模拟轧板表面凸起在轧制后压入轧板表面的情况。结果表明:表面裂纹的形成是由于轧制前铸坯上凸起区域的表面除鳞不完全,Fe、Cr等复合氧化物没有被完全除去,在轧辊和铸坯较大的摩擦力作用下,凸起区域被翻转、压延进入基体,裸露在铸坯表面的氧化物脱落,嵌入内部的氧化物由于硬度高、脆性大,与基体不易结合,在进一步轧制过程中无法焊合。
The formation causes of surface cracks on medium plate of 316 LN steel were studied by macroscopic examination,microscopic examination and chemical composition analysis. The results showed that the formation of cracks was possibly due to surface bulge of cast slab before rolling. The instrusion situation of surface bulge on rolled plate surface after rolling was simulated by finite element software ANSYS/LS-DYNA. The results showed that surface cracks were formed due to the incomplete surface descaling of bulge zone on cast slab before rolling. The composite oxides of Fe and Cr were not removed completely. The bulge zone was rolled and turned into the substrate in the rolling process because of the high friction between the roller and slab. The oxides on the surface of the slab was peeled off and embedded into the matrix. Due to the high hardness and brittleness,the embedded oxides were hardly combined with the matrix. As a result,the seaming was not realized in the further rolling process,causing surface cracks.
出处
《物理测试》
CAS
2015年第4期36-40,共5页
Physics Examination and Testing
基金
国家自然科学基金资助项目(51374151)
高等学校博士点专项科研基金资助项目(20091402110010)
山西省科技重大专项资助项目(20111101053)
