Effects of Long-term Creep at Elevated Temperatures on Rupture Ductility in 9Cr-1Mo-V-Nb-N Steel

查看全文 作　　者：Zhu, [1]Lihui; Zhao, [1]Qinxin; Gu, [1]Haicheng; Lu, Yansun [1] 机构地区：[1]Xian Jiao Tong Univ, Sch Mat Sci & Engn, Xian 710049, Peoples R China 出　　处：《Journal of Materials Science & Technology》索引1998年第14卷第3期,共5页 摘　　要：Besides the creep strength, creep ductility has also been recognized as an important material parameter, since low ductility is often associated with notch sensitivity and concomitant prema-ture failure, especially brittle fracture. Creep rupture data of 9Cr-1Mo-V-Nb-N show that the creep ductility decreases with decreasing stress at constant temperatures or with decreasing tem-perature at constant stresses. SEM and TEM were used to investigate the mechanism of creep brittleness. The results indicate that the decrease of rupture ductility after long-term creep is related to the decrease of mobile dislocation density, the coarsening and coalescence of carbides and the decrease of shear lip size. 关 键 词：MO Cr LONG