Abstract
Anisotropy of Lankford value (r value) were measured and discussed in the relation with crystallographic textures and ear behavior in the 3004 aluminum alloy sheet strain hardened by cold rolling of 86% total reduction after the hot rolling. The rvalue is small in 0° direction from the rolling direction and maximum in near 90° direction as the tensile strength shows the similar distribution. Typical and well developed rolling textures containing weak Cube, RD rotated cube and Goss components are observed in the material. The distribution profile of r value near 30° to 90° direction is estimated to depend on these texture components, however, the small r value in 0° direction is not consistent with the r value which is calculated by Taylor's model using the measured ODF's data. The actual small r value in 0° direction is considered to be caused by not only the crystallographic textures but also the deformation by shear bands that are located parallel to the transverse direction with an angle of 35° from the rolling plane. The characteristic ears in the drawn cup of this material that are six ears at 45° and 0°/180° position seem to correspond to the anisotropy of r value.
