A study on the effect of surface defect on the fatigue performance of metal component based on damage mechanics
Keywords:damage mechanics, residual stress, surface defect, multiaxial fatigue, fatigue life
In order to study the effect of surface defect on the fatigue performance of metal component, the Lemaitre and Chaboche fatigue model is investigated. Then the finite element implementation of a continuum damage mechanics formulation for multiaxial fatigue is presented, in which the coupling relationship between the damage field and the stress field is taken into account. This FE method is validated according to the experimental results for defected multiaxial fatigue for LY7075. At last the influence of defect geometry size and residual stress on structure fatigue life is analysed.