In order to characterize creep deformation in a modified 9Cr-1Mo steel, stress change tests were conducted during creep. It was confirmed that the               dislocation               behavior               during

the creep test was viscous in nature; since instant plastic strains were not observed at stress changes. The mobility of dislocations was also deduced by comparing the backward creep behavior, observed after a stress reduction, with an analysis which was based upon the idea that the backward behavior was caused by the viscous back-motion of bowed-out dislocations. The deduced dislocation mobility was in good agreement with the theoretical one.

Characterization of Creep Deformation Mechanism and Evaluation of Dislocation Mobility of Modified 9Cr-1Mo Steel by Stress Change Test. H.Hayakawa, D.Terada, F.Yoshida, H.Nakashima, Y.Gotou: Journal of the Japan Institute of Metals, 2003, 67[1], 22-6