CREEP CAVITIES AND CREEP CRACKS IN STEEL 20Cr11MoVNbNB
FU Changpu; FU Yalin; CHEN Yuhang (Xi'an University of Science and Technology;Xi'an 710048)
Cite this article:
FU Changpu; FU Yalin; CHEN Yuhang (Xi'an University of Science and Technology;Xi'an 710048). CREEP CAVITIES AND CREEP CRACKS IN STEEL 20Cr11MoVNbNB. Acta Metall Sin, 1997, 33(3): 287-291.
Abstract Studies were made on the nucleation of creep cavities and propagation of creep cracks in steel 20Cr11MoVNbNB at 550-650℃. Results show that creep cavities are mainly nucleated at the big particles of undissolved Nb (C, N) and M23C6 carbides, both of which exist at prior austenite grain boundaries and lath martensite boundaries. It is also found that creep creacks crossed the prior austenite grain boundaries and lath martensite boundaries along the direction normal to applied stress, propagated into the grains, and finally leaded to the transgranular fracture.
