FORMABLE ALUMINIUM ALLOY SHEET PRODUCT

摘要

An aluminium sheet product is formed from an alloy containing Fe 0.6 - 1.0%, Si 0.5 - 0.9% and Cu 0.3 - 0.5% and incl ies Ti and B in conventional grain refining amount. Mn is permissible in amount up to 0.2 - 0.3% but is preferably held below 0.1%. The Mg impurity content is preferably held at a very low value so as to avoid difficulties with adhesion of lacquer. The principle use of the sheet product is for the production of bottle closures and for that purpose it is preferably produced in a thickness of 0.15 - 0.25 mm. and in a quality having a low percentage earing and fine grain size. For this purpose the sheet is subjected to a temper cold rolling reduction of 30 - 60% after the last interannealing treatment. No homogenisation treatment is required before hot reduction of the cast ingot and no precipitation heat-treatment is applied to the hot-rolled product before cold rolling.