Finite Element Analysis of the Stress and Deformation Fields around the Blunting Crack Tip

The main object is to define the stress and deformation fields in a vicinity of a crack in an elasto-plastic power law hardening material under plane strain tensile loading. Hydrogen-enhanced localized plasticity (HELP) is recognized as an acceptable mechanism of hydrogen embrittlement and hydrogen-induced failure in materials. A possible way by which the HELP mechanism can bring about macroscopic material failure is through hydrogen-induced cracking. The distributions of the hydrostatic stress and plastic strain are simulated around the blunting hydrogen induced crack tip. The model of Sofronis and McMeeking is used in order to investigate the crack plasticity state. The approach is valid as long as small scale yielding conditions hold. Finite element analyses are employed to solve the boundary value problems of large strain elasto-plasticity in the vicinity of a blunting crack tip under mode I (tensile) plane-strain opening and small scale yielding conditions. Three different FEM softwares; MSC.Marc, ADVENTURE-Solid and ZeBuLoN are used for structural analysis and results are verified by the previous works. The aim is to compare the results of different rate equilibrium equations in the case of large deformation and large strain elasto-plastic analysis