Synergistic Effect of Different Plastic Deformation Modes: Molecular Dynamics Study on Strength of Crystalline/Amorphous Mixed Systems

抄録

In order to investigate the synergistic effect of different deformation modes (dislocations and local atomistic rearrangements) on the strength of mixed crystalline and amorphous materials, tensile and compressive deformation analyses of a two-dimensional binary system with various microstructures is performed through molecular dynamics simulations. The binary system is composed of atoms with two different atomic radii. By varying the mixing ratio and the interaction force between different atoms, 66 binary system models with various structures are represented, and each model is classified into three categories, crystalline, amorphous, and mixed crystalline/amorphous, through structural analysis. Deformation analysis shows that the strength of the mixed crystalline/amorphous models tends to be weaker than that of the crystal and amorphous models. The is because the edge of the force chain in the amorphous phase appears at the crystalline/amorphous interface, where dislocation release from the interface to the crystalline phase occurs easily.

 

This Paper was Originally Published in Japanese in J. Soc. Mater. Sci., Japan 71 (2022) 135–142.

Fig. 10 Force chain development around the amorphous/crystalline interface shown in Fig. 9 under compressive deformation.