INFLUENCE OF COLD-ROLLING AND ANNEALING CONDITIONS ON FORMABILITY OF ALUMINUM-ALLOY SHEET

Using an Al-Mg-Cu alloy developed for auto body panels, strip sheets a re experimentally produced by various cold-rolling and annealing proce dures. Tensile and metallographic properties of the sheets and their r elations are examined to attain high formability. The elongation is cl osely related to the grain size, and increases with the final annealin g temperature. The rolling texture influences the plastic anisotropy, the Lankford value of the sheets. The comparatively high Lankford valu es are obtained under the condition that both the intermediate and the final annealing temperatures are higher and the reduction ratio after the intermediate annealing is smaller.