Aluminum-alloy sheet and method for producing the same

Patent metadata

Field	Value
Publication number	US-9574258-B2
Application number	US-201213403389-A
Country	US
Kind code	B2
Filing date	Feb 23, 2012
Priority date	Mar 10, 2011
Publication date	Feb 21, 2017
Grant date	Feb 21, 2017

Abstract

An aluminum-alloy sheet includes 0.10 to 0.40 mass % of Si, 0.35 to 0.80 mass % of Fe, 0.10 to 0.35 mass % of Cu, 0.20 to 0.80 mass % of Mn, and 1.5 to 2.5 mass % of Mg, the balance being Al and unavoidable impurities, wherein a content ratio (Si/Fe) of the Si to the Fe is 0.75 or less, the area fraction of Mg 2 Si intermetallic compound grains having a maximum length of 1 μm or more is 0.10% or more in a region of a section of the aluminum-alloy sheet, the region being a central region in the thickness direction of the aluminum-alloy sheet, and the aluminum-alloy sheet has a proof stress of 225 to 270 N/mm 2 after having been baked at 270° C. for 20 seconds.

First claim

What is claimed is:

1. An aluminum-alloy sheet, comprising
0.10 to 0.40 mass % of Si,
0.35 to 0.80 mass % of Fe,
0.10 to 0.35 mass % of Cu,
0.20 to 0.80 mass % of Mn,
1.77 to 2.5 mass % of Mg, and
the balance being Al and unavoidable impurities,
wherein
a content ratio (Si/Fe) of Si to Fe is 0.75 or less,
an area fraction of Mg 2 Si intermetallic compound grains having a length of at least 1 μm is 0.10% or more in a central region in a thickness direction of a section of the aluminum-alloy sheet, and
the aluminum-alloy sheet has a proof stress of 225 to 270 N/mm 2 after baking at 270° C. for 20 seconds.

2. The aluminum-alloy sheet according to claim 1 , further comprising at least one of 0.10 mass % or less of Cr, 0.40 mass % or less of Zn, and 0.10 mass % or less of Ti.

3. A method for producing the aluminum-alloy sheet according to claim 1 or 2 for a resin-coated can body, the method comprising:
melting an aluminum alloy having the composition of the aluminum-alloy sheet to obtain a molten alloy and casting the alloy into a slab;
homogenizing the slab by a single heat treatment at a maximum temperature of 450° C. to 530° C. to obtain a homogenized slab;
hot rolling the homogenized slab without being cooled, at a finish rolling temperature of 300° C. to 380° C. to form a hot-rolled sheet; and
cold rolling the hot-rolled sheet without being annealed, with a total rolling reduction of 80% to 90%.

4. The method according to claim 3 , wherein the cold rolling is performed with a tandem mill.

5. The aluminum-alloy sheet according to claim 1 , comprising 0.2 to 0.69 mass % of Mn.

6. The aluminum-alloy sheet according to claim 1 , comprising 0.2 to 0.67 mass % of Mn.

7. The aluminum-alloy sheet according to claim 1 , comprising 1.88 to 2.5 mass % of Mg.

Assignees

• Inoue Yuji
• Aruga Yasuhiro
• Matsumoto Katsushi
• Tsuruda Kiyohito
• Masada Kazuharu
• Kobe Steel Ltd

Inventors

• Inoue Yuji
• Aruga Yasuhiro
• Matsumoto Katsushi
• Tsuruda Kiyohito
• Masada Kazuharu

Classifications

• C22C21/06

  with magnesium as the next major constituent · CPC title

• C22F1/047 Primary

  of alloys with magnesium as the next major constituent · CPC title

• C22C1/026

  Alloys based on aluminium · CPC title

• C22C21/08

  with silicon · CPC title