| CPC C22F 1/043 (2013.01) [C22C 21/02 (2013.01)] | 4 Claims |

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1. A method for producing an aluminum alloy extruded material, comprising:
casting a billet at a casting speed of 60 mm/min or more using an aluminum alloy,
the aluminum alloy containing, by mass: 0.50 to 1.0% of Mg, 0.80 to 1.30% of Si, 0.36 to 0.60% of Mn, 0.05 to 0.35% of Fe, 0.35% or less of Cu, less than 0.10 of Cr, less than 0.10% of Zr, less than 0.10% of Zn, 0.10% or less of Ti, and the balance being aluminum and unavoidable impurities,
the aluminum alloy having a stoichiometric Mg2Si content limited to 1.35 to 1.75% with excess Si limited to 0.33 to 0.85%, and a total Mn and Fe content of 0.41% to 0.95% by mass;
homogenizing the billet at 560 to 590° C. for 2 to 8 hours, followed by cooling the billet at a rate of 50° C./h or more;
preheating the billet at 400 to 550° C. and then extruding the billet into an aluminum alloy extruded material,
cooling the aluminum alloy extruded material immediately after extruding from 460 to 550° C. at an average cooling rate of 350° C./min or more; and
subsequently applying artificial aging treatment to the aluminum alloy extruded material.
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