It is an universal phenomenon that the dislocation are produced in metal plastic deformation, which will plays potentially value on fundamental research field for mental strengthening?and?toughening if the evolution characteristics and laws of its movable dislocation are investigated and make full used according to them features. Therefore, the transfer behavior of movable dislocation for typical metal Al was studied by atomic simulation method, and the microscopic mechanism for improving metal strengthening and toughening revealed through research the interaction between movable dislocation induced by nano-indentation and twin boundary constructed by interface engineering designing. Furthermore, the movable dislocation and phase transformation as well as adhesive effect were analyzed and compared between single and multilayer twin boundary. It was found that the plastic deformation of aluminum mental can be dominant by coordinating the amorphous generation and phase transformation behaviour. During nano-indentation process, the twin boundary has two obvious effect on movable dislocation moving changes, the one is hinder dislocation migration, the other is to induce dislocation produced a cell, which result in the transition of Burt’s vector, dislocation entanglement and generation of cross slip, it’s also the main reason to realize metal has excellent mechanical properties with strengthening?and?toughening features. The results shows that the local non-contact region on the surface of Al substrate can induce the appearance of atomic mismatch spots during loading, and When the distance between the twin boundary and the upper surface of the substrate decreases, the effect of dislocation winding and dislocation slip becomes more obvious, and the anti-adhesion effect is also decreases. In addition,?the twin boundary was treated as the the propagation of plastic ring source at dislocation emission process when substrate was continuously loaded. This results in this article provides an important theoretical source for improving metal strengthening and toughening effect, and also play an important fundamental role in promoting the physical property potential of movable dislocation-controlled micro/nano devices, and on the development of designing micro-structure with excellent mechanical properties has important significance values.
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