ALUMINUM ALLOY FOR BUTT RESISTANCE WELDING WITH SUPERIOR STRESS CORROSION CRACKING RESISTANCE AT JOINT

摘要

PURPOSE:To provide an Al-Mg alloy having high stress corrosion cracking resistance at a joint formed especially by butt resistance welding and consisting of a prescribed percentage each of Mg and Cu and the balance essentially Al. CONSTITUTION:Said Al-Mg alloy consists of, by weight, 3.0-5.0% Mg, 0.05- 1.00%, especially 0.10-0.50% Cu and the balance Al with inevitable impurities. This alloy is semiconductinously cast and hot rolled as usual, and it is optionally cold rolled and subjected to final annealing to obtain a soft rolled plate. The resulting plate has superior strength, high formability and high stress corrosion cracking resistance at a joint formed especially by flash butt welding. Accordingly, this alloy is most suitable for use as a structural material for a 2-piece wheel for a car, and it is preferably applied to a seam welded pipe, machine parts, etc. each having a butt resistance weld zone.