Grain refinement in the formability of aluminium thin cup
A refinement of the grain diameter of 300μm thick Aluminium foil through an ARB process up to four cycles followed by a stress relief annealing has increased the formability of a cup drawing. The formability in terms of LDR has increased from 1.87 in full annealed condition to 2.00 for the ARB processed sample subjected to a stress relief anneal at 200°C. In addition to an improved formability obtained in a cup formation, the combined ARB process and annealing can also reduce cup earing and wrinkle on the cup wall. This was reflected in the normal and planar anisotropy values.