Fatigue life prediction of metal structures subjected to combined thermal-acoustic loadings using a new critical plane model

In this paper, the fatigue life of metallic structures under combined thermal-acoustic loadings is predicted based on critical plane model. In order to take into account the effect of mean stresses induced by temperature loading, a new critical plane model based on shear strain is proposed. The proposed model is validated with experimental data from literature through testing four metal materials under various strain paths with zero/non-zero mean stress. It has been shown that the results estimated by the proposed model agree well with the experiment. Furthermore, the proposed model is applied to predict the fatigue life of metal structures under combined thermal-acoustic loadings, and compared with the uniaxial Goodman model. The comparison indicates that the proposed model is conservative, and the thermal loading can significantly reduce the fatigue life.