Grain boundary engineering for enhancing intergranular damage resistance of ferritic/martensitic steel P92  

作　　者：Lei Peng Shang-Ming Chen Jing-Yi Shi Yong-Jie Sun Yi-Fei Liu Yin-Zhong Shen Hong-Ya He Hui-Juan Wang Jie Tian 

机构地区：[1]State Key Laboratory of Particle Detection and Electronics,University of Science and Technology of China,Hefei 230026,China [2]School of Nuclear Science and Technology,University of Science and Technology of China,Hefei 230027,China [3]School of Materials Engineering,Shanghai University of Engineering Science,333 Long Teng Road,Shanghai 201620,China [4]Experimental Center of Engineering and Material Science,University of Science and Technology of China,Hefei 230026,China

出　　处：《Nuclear Science and Techniques》2024年第5期186-199,共14页核技术（英文）

基　　金：supported by the National Natural Science Foundation of China(Nos.12175231 and 11805131),Anhui Natural Science Foundation of China(No.2108085J05);Projects of International Cooperation and Exchanges NSFC(No.51111140389);the Collaborative Innovation Program of the Hefei Science Center,CAS(Nos.2021HSC-CIP020 and 2022HSCCIP009).

摘　　要：Ferritic/martensitic(F/M)steel is widely used as a structural material in thermal and nuclear power plants.However,it is susceptible to intergranular damage,which is a critical issue,under service conditions.In this study,to improve the resistance to intergranular damage of F/M steel,a thermomechanical process(TMP)was employed to achieve a grain boundary engineering(GBE)microstructure in F/M steel P92.The TMP,including cold-rolling thickness reduction of 6%,9%,and 12%,followed by austenitization at 1323 K for 40 min and tempering at 1053 K for 45 min,was applied to the as-received(AR)P92 steel.The prior austenite grain(PAG)size,prior austenite grain boundary character distribution(GBCD),and connectivity of prior austenite grain boundaries(PAGBs)were investigated.Compared to the AR specimen,the PAG size did not change significantly.The fraction of coincident site lattice boundaries(CSLBs,3≤Σ≤29)and Σ3^(n) boundaries along PAGBs decreased with increasing reduction ratio because the recrystallization fraction increased with increasing reduction ratio.The PAGB connectivity of the 6%deformed specimen slightly deteriorated compared with that of the AR specimen.Moreover,potentiodynamic polarization studies revealed that the intergranular damage resistance of the studied steel could be improved by increasing the fraction of CSLBs along the PAGBs,indicating that the TMP,which involves low deformation,could enhance the intergranular damage resistance.

关 键 词：Grain boundary engineering Ferritic/martensitic steel Prior austenite grain boundary character distribution Grain boundary connectivity Intergranular damage resistance 

分 类 号：TL341[核科学技术—核技术及应用]