GRAIN REFINEMENT AND TOUGHENING OF LOW CARBON LOW ALLOY MARTENSITIC STEEL WITH YIELD STRENGTH 900 MPA GRADE BY AUSFORMING
Instead of off-line quenching and tempering(QT),on-line ausforming(non-recrystallization controlled roling)and direct quenching(DQ)was employed to improve the toughness of low alloy steel with yield strength of 900 MPa Grade.Low carbon content ensured a high level of upper shelf energy,while the fine-grained martensite substructures decreased the ductile-tobrittle transition temperature and compensated the strength loss due to carbon reduction.Two mechanisms for the refinement of martensite substructure were proposed: one was the austenite grain refinement in the thickness direction,and the other was the self-accommodation of martensite variants due to austenite grain hardening.More than 200 J of Charpy V-notch impact absorbed energy at 233 K was obtained in the industrial ausformed plate,which was about the double in the traditional QT steel with the same strength grade.
ausforming martensite grain refinement HSLA steel
Zhaodong Li Xinjun Sun Zhigang Yang Qilong Yong
Department of Structural Steels,Central Iron and Steel Research Institute,No.76 Xueyuan nan Road,Hai Department of Structural Steels,Central Iron and Steel Research Institute,No.76 Xueyuan nan Road,Hai School of Materials Science and Engineering,Tsinghua University,No.1 Tsinghua Yuan,Haidian District,
国内会议
杭州
英文
195-201
2015-11-11（万方平台首次上网日期，不代表论文的发表时间）