The Effect of Stress Concentration and Material Structure on the Kinetics of Damage Accumulation

Abstract In the study we investigated development of surface microcracks under static loading of flat specimens with different geometry (smooth, key-hole and sharp notch) from low-(0.2%C), medium carbon (0.45%C) and stainless (0.12C-18Cr-9Ni) steels. The real damage estimation was carried out by studying the microcracks patterns at various stages of specimen’s deformation. The increase in damage during tension was characterized by a change in such damage parameters as concentration k-criterion and the relative area of the damaged surface S* occupied by microcracks. Staging of damage accumulation process was established by analyzing changes in damage parameters at different stages of loading. The influence of the stress concentration on the regularities of damage accumulation was analyzed.