12MnNiVR钢的连续冷却转变行为及相变动力学  

Continuous cooling transformation behavior and transformation kinetics of 12MnNiVR steel

作　　者：张志敏[1] 蔡庆伍[1] 余伟[1] 

机构地区：[1]北京科技大学冶金工程研究院,北京100083

出　　处：《材料热处理学报》2013年第4期143-147,共5页Transactions of Materials and Heat Treatment

基　　金：国家高技术研究发展计划(863)(2012AA03A508)

摘　　要：用热膨胀仪测定了12MnNiVR钢的连续冷却转变曲线,并结合显微组织观察和硬度测定,研究了低冷速下奥氏体向铁素体转变及向贝氏体转变的动力学,分析了铁素体转变及贝氏体转变的生长方式。实验钢在连续冷却过程中的计算相变动力学结果与实测相变数据吻合很好。研究结果表明实验钢在低冷速下冷却时奥氏体向铁素体转变,形核位置主要在晶棱处,生长方式主要为二维长大,奥氏体向贝氏体转变,形核位置主要在界面处,生长方式主要为一维长大。Continuous cooling transformation curves of 12MnNiVR steel were measured by a thermal dilatometer, and then transformation kinetics of austenite to ferrite at low cooling rate as well as austenite to bainite was studied and growth modes of transformed ferrite and bainite were analyzed on the basis of measured CCT curves, and observation of microstructure and hardness measurement. The calculated result of transformation kinetics for the tested steel during continuous cooling is in reasonable agreement with experimental data. Results show that nucleation sites of ferrite transformed from austenite at low cooling rate are mainly at crystal edges and ferrite grains grow mainly following two-dimensional mode whereas nucleation sites of transformed bainite are mainly at austenite grain boundaries and bainite grains grow mainly following one-dimensional mode.

关 键 词：12MnNiVR钢 连续冷却转变 相变动力学 生长方式 

分 类 号：TG151.2[金属学及工艺—热处理]