Method for manufacturing aluminum alloy exterior material for smart device

Patent metadata

Field	Value
Publication number	US-11654477-B2
Application number	US-201916672419-A
Country	US
Kind code	B2
Filing date	Nov 1, 2019
Priority date	Jul 16, 2019
Publication date	May 23, 2023
Grant date	May 23, 2023

Abstract

Provided is a method for manufacturing an aluminum alloy exterior material for smart devices which is formed not by extrusion or die casting but by a strip casting method using a rotating mold, and an aluminum alloy exterior material manufactured by the method. In accordance with an embodiment, the method includes: preparing a molten aluminum alloy; casting the molten aluminum alloy into a sheet shape using a rotating mold to form an aluminum alloy cast sheet; and anodizing the aluminum alloy cast sheet, wherein in the forming of an aluminum alloy cast sheet, X in Equation 1 below may have a value in the range of greater than 0 and equal to or less than 0.15.

X =( W Zn +W Mg +W Cu +W Si )/TC  <Equation 1>

Here, W Zn +W Mg +W Cu +W Si is the total content (wt %) of zinc, magnesium, copper and silicon) in the aluminum alloy, and TC is the thermal conductivity (W/m·K) of the rotating mold.

First claim

What is claimed is:

1. A method for manufacturing an aluminum alloy exterior material for smart devices, the method comprising:
preparing a molten aluminum alloy;
casting the molten aluminum alloy into a sheet shape using a rotating mold to form an aluminum alloy cast sheet; and
anodizing the aluminum alloy cast sheet, wherein in the forming of an aluminum alloy cast sheet, X in Equation 1 below has a value in a range of greater than 0 to equal to or less than 0.15,
X =( W Zn +W Mg +W Cu +W Si )/TC(wt %/( W/m·K ))  <Equation 1>

where W zn is the content (wt %) of the zinc (Zn) in the aluminum alloy, W Mg is the content (wt %) of the magnesium (Mg) in the aluminum alloy, W Cu is the content (wt %) of the copper (Cu) in the aluminum alloy and W Si is the content (wt %) of the silicon (Si) in the aluminum alloy, and where W Zn +W Mg +W Cu +W Si is the total content (wt %) of the zinc (Zn), magnesium (Mg), copper (Cu) and silicon (Si) in the aluminum alloy, and TC is the thermal conductivity (W/m K) of the rotating mold,
wherein the aluminum alloy cast sheet comprises a 6000 series aluminum alloy or a 7000 series aluminum alloy,
wherein the rotating mold comprises a copper twin roll, and
wherein the copper twin roll has thermal conductivity in a range of 200 W/m·K to 500 W/m·K.

2. The method of claim 1 , further comprising heat-treating the aluminum alloy cast sheet after performing forming of the aluminum alloy cast sheet.

3. The method of claim 2 , wherein the heat-treating comprises performing a solution treatment for 30 minutes to 10 hours at a temperature of 420° C. to 570° C.

4. The method of claim 3 , wherein the heat-treating further comprises, after performing the solution treatment, performing an aging treatment for 1 hour to 30 hours at a temperature of 100° C. to 250° C.

5. The method of claim 2 , further comprising cutting the aluminum alloy cast sheet after performing the forming of the aluminum alloy cast sheet.

6. The method of claim 1 , wherein the aluminum alloy cast sheet comprises:
zinc (Zn) in the range of 5 wt % to 10 wt %;
magnesium (Mg) in the range of 1 wt % to 4 wt %;
copper (Cu) in the range of greater than 0 wt % to 3 wt %;
silicon (Si) in the range of greater than 0 wt % to 0.5 wt %; and
the remainder being aluminum and inevitable impurities.

7. The method of claim 1 , wherein the aluminum alloy cast sheet comprises:
silicon (Si) in the range of greater than 0 wt % to 1.5 wt %;
magnesium (Mg) in the range of greater than 0 wt % to 1.2 wt %;
copper (Cu) in the range of greater than 0 wt % to 1 wt %;
zinc (Zn) in the range of greater than 0 wt % to 0.5 wt %; and
the remainder being aluminum and inevitable impurities.

Assignees

• Korea Inst Mach & Materials
• Korea Institute Materials Science

Inventors

• Lee Yun Soo
• Kim Hyoung Wook
• Kim Su Hyeon
• Euh Kwang Jun

Classifications

• C22F1/053

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

• B22D11/003 Primary

  Aluminium alloys · CPC title

• C25D11/04

  of aluminium or alloys based thereon · CPC title

• B22D11/0405

  Rotating moulds · CPC title

• B22D11/06

  into moulds with travelling walls, e.g. with rolls, plates, belts, caterpillars · CPC title