Method of fabricating an aluminum alloy electrical conductor

• US 4,140,549 A
• Filed: 05/12/1976
• Issued: 02/20/1979
• Est. Priority Date: 09/13/1974
• Status: Expired due to Term

• Current Assignee: Southwire Company
• Original Assignee: Southwire Company
• Inventors: Chia, E. Henry, Schoerner, Roger J.
• Primary Examiner(s): Dean, R.
• Application Number:
  US05/685,469
• Time in Patent Office: 1,014 Days
• Field of Search: 148/2, 148/3, 148/11.5 A, 148/32, 148/32.5, 75/139, 75/141, 75/142
• US Class Current: 148/551
• CPC Class Codes: B22D 11/0602 formed by a casting wheel and belt, e.g. Properzi-process
• CPC Class Codes: C22F 1/057 of alloys with copper as the next major constituent

Abstract

This invention relates to a method for continuously casting an aluminum-copper and an aluminum-copper-iron alloy having an acceptable electrical conductivity and improved elongation, bendability and tensile strength wherein the method generally comprises the steps of pouring molten aluminum alloy into the groove of a continuous casting mold, cooling the molten aluminum in the casting groove, hot forming the cast bar to form a rod and continuously coiling the rod at a temperature of from about 250° F. to 700° F.

Claims

1. A method of continuously casting an aluminum-copper-iron alloy to form an electrical conductor having a minimum conductivity of fifty-seven percent (57%) IACS comprising the steps of:

(a) pouring a molten aluminum base alloy, consisting essentially of from about 0.10 weight percent to about 1.00 weight percent copper, the remainder being aluminum with associated trace elements wherein the total concentration of trace elements is no greater than about 0.30 weight percent, into the casting groove of a continuous casting mold at a temperature above the melting point of the aluminum base alloy;

(b) cooling the molten aluminum base alloy in the casting groove to a temperature below the melting point of said alloy and removing a substantially solid cast bar from the casting groove;

(c) continuously hot forming the cast bar, at a temperature sufficient to cause substantial precipitation of aluminum-copper intermetallic compounds, to form a rod; and

(d) continuously hot coiling the rod at a temperature of from about 250°

F. to about 700°

F., thereby coarsening the intermetallic precipitates.

2. The method of claim 1 wherein the aluminum alloy consists of 99.15 weight percent aluminum with associated trace elements and 0.85 weight percent copper.

3. The method of claim 1 wherein the aluminum alloy consists of from about 99.25 to about 99.85 weight percent aluminum with associated trace elements and from about 0.15 weight percent to about 0.75 weight percent copper.

4. The method of claim 1 wherein the aluminum alloy consists of from about 0.20 weight percent to about 0.30 weight percent copper with the balance being aluminum with associated trace elements.

5. The method of claim 1 wherein the aluminum alloy consists of from about 0.10 weight percent to about 1.00 weight percent copper, from about 0.30 weight percent to about 0.95 weight percent iron and from about 98.50 weight percent to about 99.60 weight percent aluminum, said aluminum containing no more than about 0.10 weight percent each of trace elements selected from the group consisting of vanadium, silicon, manganese, magnesium, zinc, boron and titanium with the total concentration of all trace elements never exceeding about 0.30 weight percent.

6. The method of claim 5 wherein the total copper and iron concentration of the aluminum alloy does not exceed about 1.20 weight percent and the rod contains aluminum-copper-iron compounds as intermetallic precipitates..

7. A method of continuously casting an aluminum alloy to form an electrical conductor having a minimum electrical conductivity of 57% IACS and having dispersed therein particles of an aluminum-copper intermetallic compound having, after cold working, a cross-sectional diameter of up to 1 micron, said aluminum alloy consisting essentially of from about 0.10 to about 1.00 weight percent copper and from about 98.70 to about 99.90 weight percent aluminum, said aluminum containing no more than about 0.10 weight percent each of trace elements selected from the group consisting of vanadium, silicon, manganese, magnesium, zinc, boron and titanium, with the total trace element concentration never exceeding about 0.30 weight percent, comprising the steps of:

(a) pouring the molten aluminum alloy into the casting groove of a continuous casting mold at a temperature above the melting point of the alloy;

(b) cooling the molten aluminum base alloy in the casting groove to form a substantially solid cast bar and removing a cast bar from the casting groove;

(c) continuously hot forming the cast bar to form a rod at a temperature sufficient to cause intermetallic compounds to precipitate; and

(d) continuously hot coiling the rod at a temperature of from about 250°

F. to about 700°

F. thereby coarsening the intermetallic compound precipitates.

8. The method of claim 7 wherein the aluminum alloy consists of from about 99.25 to about 99.85 weight percent aluminum with associated trace elements and from about 0.15 to about 0.75 weight percent copper.

9. The method of claim 7 wherein the aluminum alloy consists of from about 0.20 to about 0.30 weight percent copper with the balance being aluminum with associated trace elements.