High proof stress Al—Zn aluminum alloy extrusion material superior in bendability

Patent metadata

Field	Value
Publication number	US-10202671-B2
Application number	US-201514707599-A
Country	US
Kind code	B2
Filing date	May 8, 2015
Priority date	May 13, 2014
Publication date	Feb 12, 2019
Grant date	Feb 12, 2019

Abstract

A high proof stress aluminum alloy extrusion material having superior bendability and crack resistance. The high proof stress aluminum alloy extrusion material is an aluminum alloy comprising: 5.0 to 7.0 wt % of zinc; 0.5 to 1.5 wt % of magnesium; 0.05 to 0.3 wt % of copper; no greater than 0.15 wt % of zirconium; 0.1 to 0.4 wt % of iron; 0.05 to 0.4 wt % of silicon; with the balance being Al and impurities, in which at least 90% of a metallographic structure is a recrystallized structure.

First claim

What is claimed is:

1. An aluminum alloy extrusion material including an aluminum alloy comprising: 5.0 to 7.0 wt % of zinc; 0.5 to 1.5 wt % of magnesium; 0.05 to 0.3 wt % of copper; no greater than 0.15 wt % of zirconium; 0.1 to 0.4 wt % of iron; 0.05 to 0.4 wt % of silicon; 0.005 to 0.12 wt % of titanium; with the balance being aluminum and impurities, wherein at least 90% of a metallographic structure is a recrystallized structure.

2. The aluminum alloy extrusion material according to claim 1 , wherein the aluminum alloy comprises at least one of: 0.05 to 0.08 wt % of zirconium; 0.05 to 0.3 wt % of chromium; 0.05 to 0.2 wt % of manganese; and 0.003 to 0.1 wt % of boron.

3. The aluminum alloy extrusion material according to claim 1 , wherein an average crystal particle diameter of the recrystallized structure is no greater than 500 μm.

4. The aluminum alloy extrusion material according to claim 1 , wherein the extrusion material has been subjected to a bending process.

5. A manufacturing method of the aluminum alloy extrusion material according to claim 1 , comprising:
homogenizing by heating and holding a billet of the aluminum alloy at 450 to 560° C. for 1 to 16 hours and then cooling to an ambient temperature;
obtaining the extrusion material by heating the billet to 400 to 570° C. and extruding at an extrusion rate of 2 to 50 m/min; and
aging treating by heating the extrusion material to 110 to 200° C. and holding for 4 to 24 hours.

6. The manufacturing method of the aluminum alloy extrusion material according to claim 5 , further comprising performing a bending process on the extrusion material having been subjected to the aging treatment.

7. A manufacturing method of the aluminum alloy extrusion material according to claim 1 , comprising:
homogenizing by heating and holding a billet of the aluminum alloy at 450 to 560° C. for 1 to 16 hours and then cooling to an ambient temperature;
obtaining the extrusion material by heating the billet to 400 to 570° C. and extruding at an extrusion rate of 2 to 50 m/min; and
aging treating by, in a first stage, performing pre-aging by heating the extrusion material to 90 to 120° C. and holding for 4 to 20 hours, and then, in a second stage, heating to 110 to 200° C., at a higher temperature than a holding temperature in the first stage, to thereby hold for 4 to 24 hours as a total holding time of the first and second stages.

8. The manufacturing method of aluminum alloy extrusion material according to claim 7 , further comprising performing a bending process on the extrusion material having been subjected to the aging treatment.

Assignees

• Nippon Light Metal Co
• Honda Motor Co Ltd

Inventors

• Xing Jie
• YATSUKURA Masato
• Sumi Shinichiro
• Lin Peizheng
• Mochizuki Shoji
• Takaki Naoki
• Sugimoto Nao

Classifications

• C22F1/053

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

• C22C21/10 Primary

  with zinc as the next major constituent · CPC title