Article révisé par les pairs
Résumé : The Cr-Mo steels are widely used in the power generation industry for equipment used at high temperatures and remaining in service for long periods of time. Under such conditions, creep is the main cause for premature failure. The evolution of the precipitate carbides and the reduction in Mo concentration in solid solution are the controlling mechanisms responsible for their properties. Estimating damage and the remaining life of power plants or high-temperature pressurized petrochemical equipment has become relatively common. As operating conditions vary considerably over time in such plants, inspection techniques are necessary to estimate the extent of damage, although these may not always provide clear evaluations of remaining life. An alternative assessment method is to use hardness measurements that can be correlated with creep damage and remaining life. In this study, using such a correlation, specimens of 2.25Cr-1Mo steel from accelerated creep tests performed under different conditions of temperature and stress have been examined. The results indicate that the Larson-Miller parameter can be used to correlate the recorded hardness values and so estimate the extent of damage and of remaining life