Influence of Geometrical Features of Meso-Defects on Damage Evolution of Metal Structure

Abstract

To study the failure process of metal structure with meso-defects, RVE (representative volume element) with various initial meso-defects were analyzed by using ABAQUS software, the parameter f (void volume fraction) of GTN damage model was regarded as the criterion of structural damage. The result shows that f increased more obvious with volume of defects for spherical defects with the same shape but different size. When the radius of defects is less than 0.15mm, the influence of defects’ volume on increases of f is clear enough. When the radius is greater than 0.15mm, the effects is diminishing. For ellipsoidal defects with the same volume but different aspect ratio, when the long axis perpendicular to the direction of load, the increased trend of f according to plastic deformation more obvious along with aspect ratio of defects. Apparently, as aspect ratio approaches infinity, f would have the fastest growth. Consequently, the bigger defect volume and aspect ratio, the more conducive for damage evolution of the metal structure.