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

摘要

Provided are: an aluminum alloy sheet for a battery lid that has excellent deformation resistance, moldability, and heat dissipation properties and that makes it possible to form an integrated explosion prevention valve having little variation in operating pressure and excellent cyclic fatigue resistance properties; and a method for producing the aluminum alloy sheet for a battery lid. The aluminum alloy sheet for a battery lid for forming an integrated explosion prevention valve is characterized by having a component composition that includes 0.85-1.50 mass% of Fe, 0.30-0.70 mass% of Mn, 0.002-0.15 mass% of Ti, less than 0.05 mass% of B, and a remainder of Al and impurities, in which the Fe/Mn ratio is controlled so as to be 1.8-3.5, and in which Si, Cu, Mg, and V present as impurities are controlled such that Si is less 0.40 mass%, Cu is less than 0.03 mass%, Mg is less than 0.05 mass%, and V is less than 0.03 mass%. The aluminum alloy sheet for a battery lid for forming an integrated explosion prevention valve is also characterized in that the 0.2% proof stress is 40 MPa or more, the elongation value is 40% or more, the conductivity is 53.0% IACS or more, a recrystallized structure is present, and the elongation value after cold rolling is performed at a rolling reduction ratio of 80% is 6.5% or more. In addition, the average crystal grain size of the recrystallized grains of the recrystallized structure is preferably 15-25 µm.