Aluminum alloy plate for battery lid for molding of integrated circular explosion-proof valve and its manufacturing method

摘要

Aluminum alloy sheet for battery lid use excellent in heat radiation ability, deformation resistance, and formability, which aluminum alloy sheet for battery lid use enabling formation of an integrated explosion-proof valve with little variation in operating pressure and excellent in cyclic fatigue resistance, and a method of production of the same are provided, the aluminum alloy sheet for battery lid use for forming an integrated explosion-proof valve having a component composition containing Fe: 1.05 to 1.50 mass%, Mn: 0.30 to 0.70 mass%, Ti: 0.002 to 0.15 mass%, and B: less than 0.04 mass%, having a balance of Al and impurities, having an Fe/Mn ratio restricted to 1.8 to 3.5, restricting, as impurities, Si to less than 0.20 mass%, Cu to less than 0.03 mass%, Mg to less than 0.05 mass%, and V to less than 0.03 mass%, having a conductivity of 53.0% IACS or more, having a 0.2% yield strength of 40 MPa or more, having a value of elongation of 40% or more, having a recrystallized structure, and having both a value of elongation after cold rolling by a rolling reduction of 80% and a value of elongation after cold rolling by a rolling reduction of 90% of 5.0% or more. Furthermore, an average grain size of the recrystallized grains of the recrystallized structure is preferably 15 to 30 µm.