Aluminum-cerium-iron electrical conductor and method for making same

• US 3,964,935 A
• Filed: 10/07/1974
• Issued: 06/22/1976
• Est. Priority Date: 04/03/1972
• Status: Expired due to Term

• Current Assignee: Southwire Company
• Original Assignee: Southwire Company
• Inventors: Wilks, Van C.
• Primary Examiner(s): Dean, R.
• Application Number:
  US05/512,821
• Time in Patent Office: 624 Days
• Field of Search: 75/138, 75/147, 29/193, 29/193.5, 29/527.7, 148/11.5 A, 148/2, 148/32, 148/32.5, 164/76
• US Class Current: 148/550
• CPC Class Codes: C22C 21/00 Alloys based on aluminium
• CPC Class Codes: C22F 1/04 of aluminium or alloys based thereon
• CPC Class Codes: Y10T 29/49991 Combined with rolling

Abstract

Aluminum alloy electrical conductors are produced from aluminum base alloys consisting essentially from about 0.20 percent to about 1.50 percent by weight cerium, from about 0.55 percent to about 1.2 percent by weight iron, with the further proviso that the combined weight amount of cerium and iron should range from about 1.2 percent to about 2.5 percent. Optionally magnesium and cobalt in small amounts, e.g., about 0.15 percent can be employed. The alloy conductors of the present invention have an electrical conductivity of at least 59% based on the Internatinal Annealed Copper Standard (IACS), and improved properties of increased thermal stability, ductility, fatigue resistance and yield strength as compared to conventional aluminum alloys with similar electrical properties. The preferred method employed utilizes continuous casting, e.g., casting wheel technique, followed immediately with continuous rolling to rod and/or wire.

Claims

1. An aluminum alloy electrical conductor manufactured in the form of an at least partially annealed wire by means of continuous casting and rolling, drawing without preliminary or intermediate anneals, and then at least partially annealing the wire, said wire having a minimum conductivity of 61% IACS in the final at least partially annealed condition and consisting essentially of from about 0.55 to about 1.2 weight percent iron, from about 0.2 to about 1.5 weight percent cerium, optionally up to about 0.15 weight percent each of cobalt and magnesium in a total amount not exceeding about 0.25 weight percent, and the remainder aluminum with associated trace elements, the combined amounts of cerium and iron ranging from at least about 1.2 percent to about 2.5 percent;

said wire having dispersed therein intermetallic precipitates comprising cerium aluminate and iron aluminate to further improve the physical properties of said conductor.

2. The aluminum alloy electrical conductor according to claim 1, wherein iron is present in an amount ranging from about 0.65 to about 1.0 percent, and cerium is present in an amount ranging from about 0.3 percent to about 1.0 percent.

3. The aluminum alloy electrical conductor according to claim 2, wherein the cerium aluminate precipitated compounds are oriented in the direction of drawing.

4. The aluminum alloy electrical conductor according to claim 1, said conductor being in the form of a fully annealed wire having a yield strength in excess of 8,000 psi.

5. The aluminum alloy electrical conductor according to claim 1, wherein the weight percentages of the constituents are as follows:

space="preserve" listing-type="tabular">cerium 0.60 percent iron 0.70 percent magnesium 0.15 percent aluminum remainder.

6. The aluminum alloy electrical conductor according to claim 1, wherein the weight percentages of the constituents are as follows:

space="preserve" listing-type="tabular">cerium 0.80 percent iron 0.70 percent aluminum remainder.

7. The aluminum alloy electrical conductor according to claim 1, wherein the weight percentages of the constituents are as follows:

space="preserve" listing-type="tabular">cerium 1.0 percent iron 0.60 percent aluminum remainder.

8. The aluminum alloy electrical conductor according to claim 1, wherein the weight percentages of the constituents are as follows:

space="preserve" listing-type="tabular">cerium 0.40 percent iron 1.0 percent aluminum remainder.

9. The aluminum alloy electrical conductor according to claim 1, wherein the weight percentages of the constituents are as follows:

space="preserve" listing-type="tabular">cerium 1.50 percent iron 0.55 percent aluminum remainder.

10. A method of preparing the aluminum alloy electrical conductor according to claim 1, comprising the steps of:

A. alloying said named constituents;

B. continuously casting the alloy in a moving mold formed between a groove in the periphery of a rotating casting wheel and a metal belt laying adjacent said groove for a portion of its length;

C. hot-rolling the cast alloy substantially immediately after casting while the cast alloy is in substantially that condition as cast to form a continuous rod;

D. drawing the rod through a series of wire-drawing dies, without any preliminary or intermediate anneals, to form wire; and

E. thereafter annealing or partially annealing the wire to achieve a conductivity of at least 61% IACS.