摘要
研究了W18Cr4V高速钢激光相变强化层的组织及奥氏体晶粒超细化的机理.强化层的组织由马氏体、残余奥氏体及未溶碳化物组成,其中片状马氏体量较多,板条马氏体量较少,其亚结构分别为孪晶和密度较高的位错.残余奥氏体量约为10%~15%,较常规热处理有明显减少,激光相变强化后晶粒度由原来的8级提高到12级.
Deals with the structure and the mechanism of grain super-refining ofthe laser phase transformation strengthening layer in a high-speed steel of W18Cr4V. Thestructure of the strengthened layer is consisted of martensite,retained austenite and undisolved carbide, in which there are a large amount of plate martensite with twinned substructure and a small amount of lath martensite with high density dislocations substructure. The amount of the retained austenite is about 10% -15 % after laser treatment,beingclearly less than that of treated by conventional treatment. The grade of grain size is increased from 8 to 12 after laser phase transformation strengthening.
基金
山东省科委资助
关键词
激光相变强化
激光热处理
高速钢
晶粒度
High-speed tool steels
Laser heating
Martensite
Refined crystaline strengthening