Quantitative analysis of surface roughness evolution in FCC polycrystalline metal during uniaxial tension

• Published in: Computational materials science 2017-05, Vol.132, p.19-29
• Main Authors: Zhang, Lei, Xu, Wujiao, Liu, Chengshang, Ma, Xin, Long, Jiang
• Format: Article
• Language: English
• Subjects: Crystal plasticity; Grain size; Orientation distribution; Periodic boundary condition; Surface roughness
• ISSN: 0927-0256; 1879-0801
• DOI: 10.1016/j.commatsci.2017.02.018

[Display omitted] •Quantitative description of surface roughness evolution was established.•Effects of material parameters on roughness evolution were quantitatively analyzed.•Two new parameters were proposed to represent the effects of grain size and texture. The purpose of this work is to present a quantitative description of surface roughness evolution in face-centered cubic (FCC) polycrystalline metal under uniaxial tension. The crystal plasticity model, in which the crystal plasticity constitutive law and the periodic boundary condition are incorporated, is established to analyze the effect of initial surface roughness, grain size and crystallographic orientation distribution on the surface roughness evolution. It is found that the surface topography during plastic straining can be divided into heterogeneous deformation surface and homogeneous deformation surface according to whether considering the heterogeneity of polycrystalline material or not. To quantitatively descript the surface roughness evolution during uniaxial tension, the concepts of equivalent grain size, which represents the comprehensive effect of grain sizes in different directions, and standard deviation of the direction cosines between crystal plane and rolling direction of grains (SD_cHR), which represents the effect of orientation distribution, are proposed. The roughness of the model with flat free surface depends approximately linearly on both the tension strain and the grain size, and exponential on the texture distribution. The uniaxial tensile test is performed to verify the accuracy of the established quantitative description of surface roughness evolution, which shows a favorable agreement with the predicted results.