Gurao N P, Suwas Satyam
Department of Materials Science and Engineering, Indian Institute of Technology, Kanpur-208016, India.
Department of Materials Engineering, Indian Institute of Science, Bangalore-560012, India.
Sci Rep. 2014 Jul 10;4:5641. doi: 10.1038/srep05641.
Scaling behaviour has been observed at mesoscopic level irrespective of crystal structure, type of boundary and operative micro-mechanisms like slip and twinning. The presence of scaling at the meso-scale accompanied with that at the nano-scale clearly demonstrates the intrinsic spanning for different deformation processes and a true universal nature of scaling. The origin of a ½ power law in deformation of crystalline materials in terms of misorientation proportional to square root of strain is attributed to importance of interfaces in deformation processes. It is proposed that materials existing in three dimensional Euclidean spaces accommodate plastic deformation by one dimensional dislocations and their interaction with two dimensional interfaces at different length scales. This gives rise to a ½ power law scaling in materials. This intrinsic relationship can be incorporated in crystal plasticity models that aim to span different length and time scales to predict the deformation response of crystalline materials accurately.
无论晶体结构、边界类型以及诸如滑移和孪生等起作用的微观机制如何,在介观尺度上都观察到了标度行为。介观尺度上的标度与纳米尺度上的标度同时存在,清楚地表明了不同变形过程的内在跨越性以及标度的真正普遍性。晶体材料变形中与应变平方根成正比的取向差方面的1/2幂律起源,归因于界面在变形过程中的重要性。有人提出,存在于三维欧几里得空间中的材料通过一维位错及其在不同长度尺度上与二维界面的相互作用来适应塑性变形。这在材料中产生了1/2幂律标度。这种内在关系可以纳入晶体塑性模型中,这些模型旨在跨越不同的长度和时间尺度,以准确预测晶体材料的变形响应。