Stress Analysis And Crack Growth Life Prediction For Selective Reinforcement Structure

In present thesis, the effects of reinforcement material parameters (such as elastic modulus,thickness and reinforcement location) on stress intensity factors (SIFs) for through-the-thicknesscracks in the aluminum alloy (2024-T3aluminum alloy) are studied by use of the linear elasticthree-dimensional finite element method based on the finite element code ABAQUS, thecorresponding fatigue crack propagation simulations are conducted. The reinforcement material isbonded to the cracked specimen through a film-adhesive, it is assumed that the delamination andfracture of reinforcement material do not happen. Some results are obtained:1. The effects of elastic modulus, thickness and reinforcement location of reinforcementmaterials on SIFs for cracks in the2024-T3aluminum alloy plate are studied. The distribution of SIFalong the thickness direction at different crack length, the curve of SIF (the relationship between thelargest SIF and crack length) and the curve of the correction coefficient for the SIF are obtained by thethree-dimensional finite element model. The formulas of SIF and correction coefficient for the SIF aresummarized.2. The fatigue crack propagation simulations are conducted for different stress ratio,0.5and0.06respectively, which include the crack closure effect. The effects of different reinforcement locationand different stiffened thickness of reinforcement material on fatigue crack growth of present modelhave been studied.