论文部分内容阅读
对82B在拉拔过程中出现的笔尖状断口进行分析,认为铸坯中心碳、锰、铬成分偏析以及轧后冷却速度过快产生了马氏体组织,相变时引起晶格畸变,由于马氏体硬度高、变形能力差,微裂纹在拉拔过程中萌生并扩展,导致断裂。这是导致笔尖状断裂的主要原因,为此通过采取措施降低铸坯成分偏析,优化轧后冷却工艺,降低马氏体组织尺寸,取得了较好的效果,解决了拉拔过程笔尖状断裂现象。
The pen nib fracture appeared during the drawing process of 82B shows that the segregation of carbon, manganese and chromium in the center of the billet and the rapid cooling after rolling produce the martensite structure and cause the lattice distortion when the phase change occurs. High hardness of martensite, poor deformability, micro-cracks in the drawing process initiation and expansion, leading to fracture. This is the main reason that leads to pen-like fracture. Therefore, by taking measures to reduce segregation of slab, optimizing post-rolling cooling process and reducing the size of martensite, good results are obtained and pen-like fracture phenomenon during drawing process is solved .