Method for producing Al-Mg aluminum alloy plate for hot blow molding and method for producing hot blow molded product

摘要

PPROBLEM TO BE SOLVED: To provide a plate material for hot blow molding having suitable hot blow moldability, suppressed in a decrease in the smoothness of molding appearance during hot-blowing, and being excellent in appearance when coated. PSOLUTION: The hot-rolled Al-Mg aluminum alloy plate comprises an alloy containing 3.5-6.0 wt.% Mg, containing at least one of 0.5-0.8 wt.% Mn and 0.05-0.20 wt.% Cr, and having an Si content controlled to at most 0.10 wt.%, an Fe content controlled to at most 0.12 wt.%, and a Cu content controlled to at most 0.10 wt.%, and the balance comprising irreversible impurities and is prepared by hot-rolling an ingot after homogenization, cold-rolling the hot- rolled product at a cold rolling rate of at least 25%, subjecting the cold-rolled product to intermediate annealing including heating the product to a temperature range of 400-550C at a rate of temperature increase of at least 1C/sec and keeping the product in this state for at longest 5 min, cold-rolling the product at a cold rolling rate of 25 to below 50%, and subjecting the cold-rolled product to the final annealing including heating the product to a temperature range of 400-550C at a rate of temperature increase of at least 1C/sec and keeping the product in this state for at longest 5 min. PCOPYRIGHT: (C)2004,JPO