2009 年 3 巻 12 号 p. 1285-1296
In this study, for prediction of free surface roughening behavior with a simple model, we focus on finite element (FE) modeling considering microscopic material inhomogeneity due to different flow stresses for each crystal grain. For this purpose, an evaluation method of microscopic material inhomogeneity using the micro Vickers hardness distribution was proposed and discussed. It was found that decreasing the ratio of the average impression size to the average grain size is necessary to express the microscopic material inhomogeneity appropriately using the hardness distribution. The flow stress-strain curve of the inhomogeneous FE model was in good agreement with those of the conventional homogeneous FE model and the experiment. Therefore, the deformation response of FE simulation considering microscopic material inhomogeneity presents a real response macroscopically. The free surface roughening obtained from FE model considering microscopic material inhomogeneity is closer to the experimental result of the plane strain bending test with decreasing indentation load in the hardness test for evaluating the microscopic inhomogeneity of the material.
