Distribution of Plastic Anisotropy in Thickness Direction for Plate

A small-cube compression test is proposed to measure local plastic anisotropy for bulk material. The small-cubic specimen with a side length of 1 mm was cut out of a thick plate of pure aluminum. It was compressed in specific directions under a well-lubricated condition. The initial square cross-section was transformed into a rectangular when the plastic-anisotropic metal was tested. For the sheet material, the Lankford-value of small-cube compression test is nearly equal to that of a conventional tensile test. The anisotropic coefficients, namely F, G, H, and N, of Hill's quadratic yield criterion (1948) are calculated from Lankford-values which are measure by small-cube compression test. Also anisotropic coefficients L and M are calculated to measure planar anisotropy on the planes which normal to rolling- and width direction. It is found that plastic anisotropy is distributed in thickness direction for thick plate of pure aluminum. And the distribution is influence on the deformation of thick plate upsetting. Then, this deformation is verified by FE analysis considering anisotropy.