Effect of Hydrogen on the plastic deformation characteristics of closed-packed and BCC metals

Abstract

A new model has been proposed for homogeneous and heterogenous alloys, it characterizes three variables mobile and immobile dislocation in cell interiors and immobile dislocations in the cell walls. The evolution law is proposed for each dislocation population taking into account three phenomena namely dislocation annihilation, dislocations locks, and dislocations dipole and equations take under consideration of active glide system, thus introducing the evolution of texture in second-phase alloy with the help of the Taylor factor as polycrystal material is used here. The Hydrogen enhanced localized plasticity (HELP) is a mechanism which is adding valuable understanding to the simulation observations for hydrogen embrittlement. The effect of this mechanism on the material is modelled under the influence of hydrogen segregation, decreases the barriers which obstruct the dislocation motion and thus induces plasticity. The Hydrogen takes up both the Trapping Sites and Normal Interstitial Lattice Sites (NILS) connected with plastic deformations. The uniaxial tension under plain strain conditions is taken into account for localized plastic flow stress and plastic deformation. The above model is used to find the effect of hydrogen in microstructure evolution. The edge dislocations are taken into account under the considered volume in which the phenomenon of segregation of hydrogen solute atoms takes place, this can be shown by plotting the corresponding contour plots and thus trying to evaluate the hardening behaviour of alloy in the presence of hydrogen by plotting the stress-strain curves with different parameters. Furthermore, based on the study of this paper, our interest is to find the three main objectives. Firstly, the shielding effect of hydrogen for edge dislocations. Secondly, reduction in activation energy. Thirdly, reduction in dislocation line energy due to solute segregation.