Wang Mingzhi, Wu Jianjun, Wu Hongfei, Zhang Zengkun, Fan He
School of Mechanical Engineering, Northwestern Polytechnical University, Xi'an 710072, China.
Materials (Basel). 2017 Sep 11;10(9):1065. doi: 10.3390/ma10091065.
In this paper, a methodology is presented for obtaining the plastic anisotropy of bulk metallic materials using cross-sectional indentation. This method relies on spherical indentation on the free edge of a specimen, and examining the out-of-plane residual deformation contour persisting on the cross-section after unloading. Results obtained from numerical simulation revealed that some important aspects of the out-of-plane residual deformation field are only sensitive to the extent of the material plastic anisotropy, and insensitive to strain hardening, yield strain, elastic anisotropy, and the selected displacement threshold value. An explicit equation is presented to correlate the plastic anisotropy with the characteristic parameter of the bottom shape of residual deformation contour, and it is used to uniquely determine the material plastic anisotropy in cross-sectional indentation. Effectiveness of the proposed method is verified by application on magnesium alloy AZ31B, and the plastic anisotropy parameter obtained from indentation and uniaxial tests show good agreement.
本文提出了一种利用横截面压痕获取大块金属材料塑性各向异性的方法。该方法基于对试样自由边缘进行球形压痕，并检查卸载后横截面上持续存在的面外残余变形轮廓。数值模拟结果表明，面外残余变形场的一些重要方面仅对材料塑性各向异性程度敏感，而对应变硬化、屈服应变、弹性各向异性和所选位移阈值不敏感。提出了一个显式方程，将塑性各向异性与残余变形轮廓底部形状的特征参数相关联，并用于唯一确定横截面压痕中的材料塑性各向异性。通过在镁合金AZ31B上的应用验证了该方法的有效性，从压痕和单轴试验获得的塑性各向异性参数显示出良好的一致性。
