Analysis of Thermomechanical Fatigue by using Finite Element Post-pro

Lifetime of a standard dog-bone specimen is assessed under the action of various thermomechanical fatigue loadings. Mechanical and thermal cycles were assumed to occur concurrently and the special effect of phasing between thermal cycles and strains cycles was emphasized. The methodology used is based on finite element post-processing analysis by specialized fatigue software package that takes into account damage from three primary sources: fatigue, oxidation and creep. A parametric study has shown that thermomechanical fatigue is not always more damaging than the isothermal case. In the range of parameters investigated the out-of-phase thermomechanical fatigue was found to be more severe than the in-phase one