特厚P20模具钢加工困难的原因分析与控制措施  

Reason Analysis and Control Measures of Processing Difficulty on Extra-thick P20 Steel Plates

作　　者：李声延 张超 廖桑桑 董富军 Li Shengyan;Zhang Chao;Liao Sangsang;Dong Fujun(Xinyu Iron&Steel Group Co.,L td.)

机构地区：[1]新余钢铁股份有限公司,江西省新余市338000

出　　处：《安徽冶金》2019年第3期12-15,共4页Anhui Metallurgy

摘　　要：根据用户反映厚度在80mm以上的P20模具钢,普遍存在机械加工困难的情况。经过取样分析发现,钢板芯部存在较为严重的C、Mn等奥氏体强稳定元素偏析,使该部位的过冷奥氏体不易分解,且芯部形成大量的马氏体和残余奥氏体的混合组织,使芯部硬度远大于其他部位,影响了钢板的加工和使用。通过优化连铸、轧制及热处理工艺,减轻了钢板的芯部偏析;降低了芯部残余奥氏体量,改善了P20钢板的使用和加工性能。According to the feedback of costumers,the P20 steel plates which were more than 80mm thickness,were very difficult to process.After sampling analysis,it is found that there is a serious austenite strong stable element segregation in the core of the steel plate,which makes the supercooled austenite in this part difficult to decompose,and a large amount of martensite and retained austenite are formed in the core of the steel plate.The mixed structure,the hardness of the core of the steel plate is much larger than other parts which affects the processing and use of the steel plate.By optimizing the continuous casting,rolling and heat treatment processes,the core segregation of the steel plate is reduced;the amount of retained austenite in the core of the steel plate is reduced,and the use and processing properties of the P20 steel plate are improved.

关 键 词：P20钢 偏析 残余奥氏体 

分 类 号：TG1[金属学及工艺—金属学]