6xxx Series Al Alloy Sheets with High Formability Produced by Twin-roll Strip Casting and Asymmetric Rolling

Abstract

We report on the feasibility of producing 6xxx series Al alloy sheets using a combination of twin-roll strip casting and asymmetric rolling. The Al alloy sheets produced in this study exhibited an excellent formability ((r) over bar = 1.2, Delta r = 0.17) and mechanical properties (sigma(TS) similar to 260 MPa, epsilon > 30%), which cannot be feasibly obtained via the conventional technique based on ingot casting and conventional rolling. The enhanced formability as evaluated in terms of (r) over bar and Delta r was clarified by examining the evolution of textures associated with strip casting and subsequent thermo-mechanical treatments. The evaluation of the formability leads us to conclude that the combined technique based on strip casting and asymmetric rolling is a feasible process for enhancing the formability of Al alloy sheets to a level beyond which the conventional technique can reach.