Al-Mg-Si-BASED ALUMINUM ALLOY SHEET FOR AUTOMOBILE PANEL AND MANUFACTURING METHOD THEREFOR

• Main Authors: TAKIGUCHI KOICHIRO, SHINZATO YOSHIFUMI
• Format: Patent
• Language: English; Japanese
• Published: 13.04.2015
• Subjects: ALLOYS; CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS ANDNON-FERROUS ALLOYS; CHEMISTRY; FERROUS OR NON-FERROUS ALLOYS; METALLURGY; TREATMENT OF ALLOYS OR NON-FERROUS METALS

PROBLEM TO BE SOLVED: To provide an Al-Mg-Si-based aluminum alloy sheet for automobile panel excellent in press moldability, bendability capable of flat hem processing, shape freezing property, coating galling curability and corrosion resistance, and to provide a manufacturing method therefor.SOLUTION: A Al-Mg-Si-based aluminum alloy sheet for automobile panel contains Si:0.4 to 1.5%, Mg:0.2 to 1.2%, Cu:0.001 to 1.0%, Zn:0.5% or less, Ti:0.1% or less, B:50 ppm or less, one or more kind of Mn:0.30% or less, Cr:0.20% or less and Zr:0.15% or less, and the balance Al with inevitable impurities. A Cube direction density distribution at 1/4 depth part of sheet thickness from a surface is in a range of 10 to 25, an average of r value r(r=(r+r+r×2)/4) is 0.50 or more, an absolute value of an in-plane anisotropy index of the r value r( r=(r+r-r×2)/2) is 0.30 or less and an average crystal particle diameter is 50 μm or less. 【課題】プレス成形性、フラットヘム加工が可能な曲げ加工性、形状凍結性、塗装焼付硬化性、及び耐食性のすべてに優れた自動車パネル用Ａｌ−Ｍｇ−Ｓｉ系アルミニウム合金板及びその製造方法を提供すること。【解決手段】Ｓｉ：０．４〜１．５％、Ｍｇ：０．２〜１．２％、Ｃｕ：０．００１〜１．０％、Ｚｎ：０．５％以下、Ｔｉ：０．１％以下、Ｂ：５０ｐｐｍ以下を含有し、Ｍｎ：０．３０％以下、Ｃｒ：０．２０％以下、Ｚｒ：０．１５％以下のいずれか１種又は２種以上を含有し、残部がＡｌおよび不可避不純物からなる。表面から板厚の１／４深さ部分におけるＣｕｂｅ方位密度分布が１０〜２５の範囲、ｒ値の平均値ｒave（ｒave＝（ｒ0＋ｒ90＋ｒ45?２）／４）が０．５０以上、ｒ値の面内異方性指数 ｒ（ ｒ＝（ｒ0＋ｒ90−ｒ45?２）／２）の絶対値が０．３０以下、平均結晶粒径が５０μｍ以下である。【選択図】なし