Investigation of creep crack growth. A comparison between experimental and numerical results.

Creep crack in the 21 CrMoNiV 5 7 stell can be described by a power law using the C * integral. At the lower end of the data plot, some indications of size (triaxiality) dependences seem to exist. Calculations on the basis of a Norton law for the minimum-creep rate of uniaxial tension specimens are already in good agreement with experimental results. The consideration of primary creep is desirable for a more realistic simulation and for better understanding of the whole. A stationary model is adequate to simulate the first part of an experiment where crack growth plays no specific role. If crack growth is significant, calculations including crack growth under plane-strain and plane-stress situations supply lower and upper bounds, respectively to the experimental results.