A composite model for residual creep life assessment in T/P92 heat-resistant steel

In this paper, a composite model is proposed to describe the overall creep deformation by combining the power and logarithmic laws and considering the relationship between strengthening and softening in the creep deformation. The results demonstrate that the proposed composite model can fit well the creep curves of T/P92 heat-resistant steel under different stress and temperature values. Based on the relationship between the model parameter K and creep life, an extrapolation method of residual creep life denoted as the K-parameter method is proposed. The results demonstrate that the K-parameter method has high prediction accuracy for both low and high stress creeps under different temperatures. The proposed method has the potential for predicting the long-term creep life based on the primary creep data.