A continuum damage model for prediction of crack initiation life of pitting corrosion and fatigue

Abstract

Corrosion fatigue damage can lead to degradation of engineering structures and components. As a major stage of the total corrosion fatigue life, the crack initiation of pitting corrosion and fatigue is studied. A continuum damage mechanics model for predicting the crack initiation life of pitting corrosion fatigue is presented based on a pure fatigue damage model and a fracture-mechanics-based pit-to-crack transition criterion. The synergistic effect of pitting corrosion and fatigue are quantified as a time-varying amplification of the fatigue stress field. The proposed model is validated by corrosion fatigue test data of two different metallic materials. The predicted curves of corrosion fatigue crack initiation life are in good agreement with the test data. The model demonstrates a good prediction of corrosion fatigue crack initiation life, i.e., corrosion fatigue life is always lower than fatigue life, and the lower the stress, the more significant the life reduction.

Effect of individualized narrative nursing mode on recovery of elderly patients with fracture complicated with cerebrovascular accident

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Optimization towards Walker’s equation using intrinsic damage dissipation energy

“…Next, the generalized damage driving force Y is expressed as follows regardless of anisotropy (Yang et al, 2022):…”

“…Next, the generalized damage driving force Y is expressed as follows regardless of anisotropy (Yang et al., 2022): Where R ν denotes the triaxiality function, and σeq is the von Mises stress. It should be noted that equation (5) was established without considering the crack-closure effect under compression stress.…”

Application of continuum damage mechanics in fatigue assessment of A516 steel specimens considering residual stresses

“…Gonzalez et al (2022) presented numerical analysis of damage evolution in wire drawing process considering bilinear path of damage. Yang et al (2022) used the CDM to predict fatigue crack initiation life of pitting corrosion fatigue. The model is based on pure fatigue damage model and a fracture-mechanics-based pitto-crack transition criterion.…”

“…(2022) presented numerical analysis of damage evolution in wire drawing process considering bilinear path of damage. Yang et al. (2022) used the CDM to predict fatigue crack initiation life of pitting corrosion fatigue.…”