Creep Life Evaluation Research On1.25Cr0.5MoSi Material

Larson-Miller creep life evaluation method was used in residual life assessment, it required that some short-time high temperature and high stress creep rupture tests should be carried out in order to extrapolate, a long time extrapolation without considering materials’ aging and damage that made extrapolation confidence drop. A new creep life assessment method had been used widely overseas, which was called the Omega creep life assessment method. American Materials Council laughed this Omega project on remaining life assessment of the components in1986, it could be used in life prediction of high temperature component only through carrying out creep test in the design stress and operating temperature. In this paper,1.25Cr0.5MoSi material was used to carry out uniaxial creep tests and small punch creep (SPC) tests, then the creep data are both analyzed using the Omega method. Such conclusions are shown as follows.1. Ω and initial creep strain rate ε0are obtained through uniaxial creep tests with different stress and the same temperature550℃.2. Practical rupture time is compared with the predicted rupture time using Omega method, the result is relatively correct.3. The SPC Omega and initial deflection rate also can be obtained through carrying out SPC tests and then analyzed using the Omega method.