Grain structure and texture in aluminium alloy AA5083 after equal angular channel extrusion, warm rolling and subsequent annealing

摘要

An aluminium alloy AA5083, having a submicrometre grain structure generated by equal angular channel extrusion, was rolled at ～200°C to make flat sheets with 37.5 to 75% thickness reductions. The evolution of grain structure and texture upon warm rolling and subsequent annealing was studied by transmission electron microscopy, scanning electron microscopy and X-ray diffraction technique. It has been demonstrated that dynamic recovery occurs during the warm rolling, the submicrometre grain structure could be retained with low rolling reduction, but as the reduction increases it develops into a cell structure, and after subsequent annealing, an equiaxed fine grain structure of ～5 μm mean size is obtained which is thermally stable at temperature as high as 500°C.