Life Prediction of Low Alloy Ferritic Steels Based upon the Tertiary Creep Behavior

摘要

In the present work, the applicability of the PHI projection to the life prediction for 1.25Cr-0.5Mo and 2.25Cr-1 Mo steel has been examined. The linear relationship between strain rate and strain at the tertiary creep stage is observable and its slope, which is equivalent to PHI_4 in the PHI projection technique, can be uniquely correlated with rupture life independently of chemical compositions, creep strength and testing conditions. Therefore, it can be considered that strain rate monitoring for the remnant life prediction is very effective to improve the accuracy of the life assessment, especially for parent material of a low alloy ferritic steel in which creep cavitation is rather unlikely.