Stochastic modelling of the small disc creep test

Abstract

Obtaining accurate estimates of remanent creep life is currently of great importance to the power generating industry. The small disc creep test promises to be a useful way forward in this respect and this paper develops a stochastic finite element model of the small creep disc test. The model can be considered as a stochastic version of that used by the author, which is based on realistic creep deformations laws, including strain hardening, thermal softening and damage accumulation for 0·5Cr–0·5Mo–0·25V steel. This extension was necessary to validate the models predictions in the presence of the substantial experimental scatter that is present in existing minidisc test data. It is shown that the models predictions are capable of replicating the available experimental data to be within the approximate 99% confidence intervals for the model.