基于二维离散位错动力学的塑性变形研究进展

Two-dimensional discrete dislocation dynamics (2D-DDD) model is one of the effective methods to investigate the plastic deformation behavior of materials under complex loading conditions at micro scale. Based on the existent modelling framework, three main developments regarding the DDD methodology were reviewed. The algorithm framework based on superposition principle in 2D-DDD was first introduced. The introduction of anisotropic elastic fields effectively extends the applications of discrete dislocation dynamics model in polycrystalline and multi-phase materials. Then the dislocation escape mechanisms related to the strain rate sensitivity were discussed systematically. By introducing the thermally activated dislocation escape mechanism from pinning barriers, the prediction of strain rate sensitivity at low strain rate regions was realized. Finally, the interactions between dislocations and interfaces were discussed. The developments in the modelling methodology together with the applications to solve real-world problems were analyzed, aiming at providing theoretical guidance for the research in the plastic deformation mechanisms of metals.