Prediction of grain boundary stress fields induced by the impingement of persistent slip bands

International audiencePersistent slip band (PSB) Grain boundary (GB) crack initiation is widely observed and documented. Therefore, the prediction of stress fields at PSB-GB interfaces in polycrystals subjected to cyclic deformation is necessary to predict micro-crack initiation. Our FE simulations are based on physically based models, accounting for (i) cubic elasticity and crystal CSS behavior using single crystal data and (ii) production, annihilation, and diffusion of vacancies inducing an increasing free dilatation of PSBs, without using any fitted parameter. We investigate the impact of grain size and PSB width on GB stress fields for both Austenitic stainless Steel and Copper polycrystals. The predicted stress fields will be used to predict the number of cycles to initiate GB micro-cracks