Host: The Japan Society of Mechanical Engineers
Name : [in Japanese]
Date : September 08, 2019 - September 11, 2019
Creep damage preferentially extends at a stress concentration portion under multiaxial stress. It is necessary to clarify the relationship between the creep damage extension process under the multiaxial stress states. In this study, creep tests using a plain specimen and two kinds of round notch bar specimens with different notch radius (notch tip radius 0.5 mm (R0.5) and 2.0 mm (R2.0)) on a 2.25Cr-1Mo steel were carried out. Creep rupture times of the notch specimens were longer than those of the plain specimens. Creep rupture times of R0.5 was longer than those of R2.0 notch specimens. Greater number of voids was observed at around 0.5 mm from notch root in R0.5, and around center of the specimen in R2.0. The finite element creep analysis of the notch specimens showed the three stress component took the maximum values at around 0.5 mm from notch root in R0.5, and around center of the specimen in R 2.0. It was found that these stress component distribution tendencies correspond with the distribution tendencies of the void number density.
