The difference of the creep curves of P92 steel was comparatively analyzed by theta projection method and composite model. The results show that both the creep-time curves of P92 steel with two methods have a higher accuracy. However, when describing the creep rate-time curves, the theta projection method exhibits big error, while, the composite model can show more accurate results; When extrapolating creep rate, the theta projection method has large deflection, while, the composite model can predict more near the actual trend. When extrapolating creep rupture life based on creep curves,the results show that the fracture strain between 5% and 50% has little effect on the life prediction. The values of endurance life extrapolated by the two models are approximately the same.
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