Provided is a surface hardening method for surface hardening a sulfuric acid-anodized aluminum alloy oxide layer, which includes: pre-treatment in which various foreign substances, including an oxide film, attached to a surface of an aluminum alloy are removed; sealing treatment in which the aluminum alloy having been subjected to the pre-treatment is immersed in a sealing solution, whereby fine pores formed in a film are sealed; and heat treatment in which the aluminum alloy having been subjected to the sealing treatment is charged to, and thermally treated in, a heat treatment furnace and then naturally cooled. By lowering the withstand voltage of an aluminum alloy oxide layer and increasing the hardness by subjecting the same to sealing treatment and subsequent post-heat treatment, the present invention has the effect of providing an environmentally-friendly and crack-free lightweight material that can replace steel products.

Some variations provide an aluminum alloy feedstock for additive manufacturing, the aluminum alloy feedstock comprising from 79.8 wt % to 88.3 wt % aluminum; from 1.1 wt % to 2.1 wt % copper; from 3.0 wt % to 4.6 wt % magnesium; from 7.1 wt % to 9.0 wt % zinc; and from 0.5 wt % to 2.8 wt % zirconium as a grain-refiner element. The aluminum alloy feedstock may be in the form of an ingot powder. In some variations, the aluminum alloy feedstock comprises from 81.3 wt % to about 87.8 wt % aluminum; from 1.2 wt % to 2.0 wt % copper; from 3.2 wt % to 4.4 wt % magnesium; from 7.3 wt % to 8.7 wt % zinc; and from 0.5 wt % to 2.8 wt % zirconium.

Some variations provide an aluminum alloy feedstock for additive manufacturing, the aluminum alloy feedstock comprising from 79.8 wt % to 88.3 wt % aluminum; from 1.1 wt % to 2.1 wt % copper; from 3.0 wt % to 4.6 wt % magnesium; from 7.1 wt % to 9.0 wt % zinc; and from 0.5 wt % to 2.8 wt % zirconium as a grain-refiner element. The aluminum alloy feedstock may be in the form of an ingot powder. In some variations, the aluminum alloy feedstock comprises from 81.3 wt % to about 87.8 wt % aluminum; from 1.2 wt % to 2.0 wt % copper; from 3.2 wt % to 4.4 wt % magnesium; from 7.3 wt % to 8.7 wt % zinc; and from 0.5 wt % to 2.8 wt % zirconium.

A sheet or strip made of a hardenable aluminum alloy, a vehicle part made therefrom, a use, and a method for producing the sheet or strip are disclosed. In order to insure a powerful paint bake response (PBR), it is proposed for the aluminum alloy to have from 4.0 to 5.5 wt % magnesium (Mg) and from 2.5 to 5.5 wt % zinc (Zn) and for it to be in the T4-FH state, wherein the wt % of magnesium (Mg) is greater than the wt % of zinc (Zn).

A sheet or strip made of a hardenable aluminum alloy, a vehicle part made therefrom, a use, and a method for producing the sheet or strip are disclosed. In order to insure a powerful paint bake response (PBR), it is proposed for the aluminum alloy to have from 4.0 to 5.5 wt % magnesium (Mg) and from 2.5 to 5.5 wt % zinc (Zn) and for it to be in the T4-FH state, wherein the wt % of magnesium (Mg) is greater than the wt % of zinc (Zn).

This application discloses aluminum alloy products, such as can body stock and can end stock, that have improved processing qualities in high-speed production equipment due to engineered surfaces. For can body stock, processing is improved by providing at least two different surface roughnesses. For can end stock, processing is improved by reducing anisotropy at least at the top and bottom surfaces of the can end stock.

An aluminum alloy foil having a composition contains Si: 0.5 mass % or less, Fe: 0.2 mass % or more and 2.0 mass % or less, Mg: more than 1.5 mass % and 5.0 mass % or less, and Al balance containing inevitable impurities. In the aluminum alloy foil, Mn is desirably 0.1 mass % or less in the inevitable impurities, and preferably, the tensile strength is 180 MPa or more, the elongation is 15% or more, and the average crystal grain diameter is 25 μm or less.

The invention discloses a high-throughout continuous casting and rolling Al—Mg—Mn alloy plate for ships and the preparation process thereof. The chemical components of the Al—Mg—Mn alloy in percentage by mass percentage are: Mg: 0.80-2.80%, Mn: 0.00-1.40%, Zr: 0.10-0.50%, Cr: 0.15-0.35%, Sr: 0.00-0.10%, Er: 0.00-0.60%, Si: 0.10-0.40%, Cu: 0.01-0.10%, Ti: 0.01-0.05%, Fe: 0.00-0.40% and the rest is Al. The preparation processes mainly include smelting and melt treatment, continuous casting, continuous rolling and cold rolling. The invention solves the problems of easy segregation, low strength and toughness and poor formability in the preparation of high-throughout continuous casting and rolling Al—Mg—Mn plates for ships.

The invention discloses a high-throughout continuous casting and rolling Al—Mg—Mn alloy plate for ships and the preparation process thereof. The chemical components of the Al—Mg—Mn alloy in percentage by mass percentage are: Mg: 0.80-2.80%, Mn: 0.00-1.40%, Zr: 0.10-0.50%, Cr: 0.15-0.35%, Sr: 0.00-0.10%, Er: 0.00-0.60%, Si: 0.10-0.40%, Cu: 0.01-0.10%, Ti: 0.01-0.05%, Fe: 0.00-0.40% and the rest is Al. The preparation processes mainly include smelting and melt treatment, continuous casting, continuous rolling and cold rolling. The invention solves the problems of easy segregation, low strength and toughness and poor formability in the preparation of high-throughout continuous casting and rolling Al—Mg—Mn plates for ships.

An aluminum alloy contains equal to or more than 0.005 mass % and equal to or less than 2.2 mass % of Fe, and a remainder of Al and an inevitable impurity. In a transverse section of the aluminum alloy wire, a surface-layer void measurement region in a shape of a rectangle having a short side length of 30 μm and a long side length of 50 μm is defined within a surface layer region extending from a surface of the aluminum alloy wire by 30 μm in a depth direction, and a total cross-sectional area of voids in the surface-layer void measurement region is equal to or less than 2 μm.sup.2.