Anisotropic effects in elastic and incipient plastic deformation under (001), (110), and (111) nanoindentation of Al and Cu
Anisotropic effects in elastic and incipient plastic deformation under (001), (110), and (111) nanoindentation of Al and Cu
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DOI：
10.1103/physrevb.75.035415
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发表时间：
2007-01
影响因子：
3.7
通讯作者：
T. Tsuru;Y. Shibutani
中科院分区：
文献类型：
--
作者：
T. Tsuru;Y. Shibutani
对 001、110 和 111 纳米压痕进行原子模拟，以研究纳米压痕下弹性和初塑性行为的各向异性效应。我们比较了单晶铝和铜两种材料，重点关注它们各向异性特性之间的巨大差异。 Al 在弹性变形过程中的压痕载荷深度行为表现出轻微的各向异性，而 Cu 的压痕载荷深度随压痕轴变化很大。此外，初始塑性变形，即位错成核，很大程度上取决于预测的滑移系统。当用小半径的球形压头压入时，位错会在表面发射，而集体位错发射则发生在材料内部。在材料内位错发射的情况下，临界平均压力是位错成核的重要指标，是两种材料中压痕轴固有的。
Atomistic simulations of 001 , 110 , and 111 nanoindentation are performed to investigate anisotropic effects in elastic and incipient plastic behavior under nanoindentation. We compared two materials, singlecrystalline Al and Cu, focusing on the large difference between their anisotropic properties. The indent loaddepth behavior of Al during elastic deformation exhibits slight anisotropy, while that of Cu varies greatly according to the indentation axis. In addition, incipient plastic deformation, that is, dislocation nucleation, depends largely on the predicted slip system. While dislocations are emitted on the surface when indented by a spherical indenter with small radius, collective dislocation emission occurs from within the material. In the case of dislocation emission within the material, the critical mean pressure, which is an important indicator of dislocation nucleation, is inherent to the indentation axis in both materials.