Effect of Crystal Grain Size on Strain Localization -Observation of Surface Temperature Distribution under Deformation-
Hidetoshi SAKAMOTO, Jian SHI and Eiji NAKAMACHI
Abstract:The stress-strain characteristics and plastic behaviors of Aluminum alloy were examined by tensile test and infrared thermo-viewer. Al-Mg FCC@polycrystalline sheet plates icrystal grain size d=12, 42, 3000Ęm j were used. The effect of grain size and initial orientation distribution on the harding evolution, strain localization and crystal rotation by using X-ray diffraction and ODF analyses. Furthermore, the behaviors of the plastic deformation and the fracture were continuously observed by using the thermo-viewer in order to make clear the effect of the different crystal grain sizes on macroscopic local plastic behavior. The results obtained in this study are summarized as follows; (1) The strength level increase with decreasing crystal grain size, (2) The lager crystal grain, the quicker the strain localization occurs, (3) By making differential thermal images, a macroscopic local plastic deformation can be estimated. Key Words:Strain concentration, Local plastic behavior, Thermo-viewer, Crystal grain size effect