逆相变退火对连铸坯组织和力学性能的影响  

Effect of ART-Annealing on Microstructure and Mechanical Properties of Continuous Casting Billet

作　　者：占炜[1,2] 胡俊[1,2] 徐国富[1,2] 王存宇[2] 曹文全[2] 董瀚[2] 

机构地区：[1]华中科技大学材料科学与工程学院,湖北武汉430074 [2]钢铁研究总院结构材料研究所,北京100081

出　　处：《钢铁》2013年第3期66-70,共5页Iron and Steel

基　　金：国家973计划资助项目(2010CB630803)

摘　　要：研究了逆相变退火温度对0.1C5Mn钢连铸坯的组织结构和力学性能的影响规律,采用SEM进行组织结构的表征,利用XRD技术分析连铸坯退火后奥氏体含量,并测试了退火试样的力学拉伸性能。试验结果表明,连铸坯退火过程中发生奥氏体逆转变且在较低退火温度下有少量碳化物析出,随着退火温度升高,奥氏体含量先增加后减少,析出物逐渐溶解消失。提高退火温度可以显著提高试验钢的抗拉强度但却降低它的屈服强度,另外随退火温度升高,断后伸长率和强塑积先增高后降低。在625～650℃退火,可以获得20%～25%的伸长率。研究结果说明利用逆转变退火可以大幅度提高中锰钢铸坯的力学性能。The effects of annealing temperature in the intercritical region on microstructure and mechanical properties of 0.1CSMn continuous casting billet were investigated. Scanning electron microscopy was used to characterize microstructure evolution during annealing process. The residual austenite content in the continuous casting billet after being annealed was measured by X-ray diffraction. It is found that carbides precipitate in the matrix on a low annea- ling temperature and then it is decreased with increasing annealing temperature. In addition, increasing annealing temperature increases the tensile strength but decreases the yield strength. Furthermore, with the increasing of annealing temperature increase the product of tensile strength to total elongation tensile strength first increases with temperature high up to 650 ℃ and then decreases with further increasing of annealing temperature. The total elonga- tion of the steels annealed at 625-650℃ could be high up to 20%-25%, indicating that intercritical annealing for the medium-Mn steels could be applied to improve the mechanical properties of the cast billets of medium-Mn steels.

关 键 词：连铸 退火温度 逆相变退火 

分 类 号：TF777[冶金工程—钢铁冶金]