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arXiv · 1712.08909

Anisotropic Deformation in the Compressions of Single Crystalline Copper Nanoparticles

Jianjun Bian·Hao Zhang·Xinrui Niu·Gangfeng Wang
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Abstract

Atomistic simulations are performed to probe the anisotropic deformation in the compressions of face-centred-cubic metallic nanoparticles. In the elastic regime, the compressive load-depth behaviors can be characterized by the classical Hertzian model or flat punch model, depending on the surface configuration beneath indenter. On the onset of plasticity, atomic-scale surface steps serve as the source of heterogeneous dislocation in nanoparticle, which is distinct from indenting bulk materials. Under [111] compression, the gliding of jogged dislocation takes over the dominant plastic deformation. The plasticity is governed by nucleation and exhaustion of extended dislocation ribbons in [110] compression. Twin boundary migration mainly sustain the plastic deformation under [112] compression. This study is helpful to extract the mechanical properties of metallic nanoparticles and understand their anisotropic deformation behaviors.

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Jianjun Bian, Hao Zhang, Xinrui Niu, Gangfeng Wang. 2017-12-24. Anisotropic Deformation in the Compressions of Single Crystalline Copper Nanoparticles. https://doi.org/10.3390/cryst8030116

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