Electrical cable with improved resistance to galvanic corrosion

• US 10,734,130 B2
• Filed: 04/06/2017
• Issued: 08/04/2020
• Est. Priority Date: 04/11/2016
• Status: Active Grant

• Current Assignee: Nexans Incorporated (Nokia Corporation)
• Original Assignee: Nexans Incorporated (Nokia Corporation)
• Inventors: Dablement, Sebastien, Morice, Stephane
• Primary Examiner(s): Thompson, Timothy J
• Assistant Examiner(s): McAllister, Michael F
• Application Number:
  US16/092,145
• Publication Number:
  US 20190164660A1
• Time in Patent Office: 1,216 Days
• Field of Search: 174 74 R
• CPC Class Codes: B21C 1/003 Drawing materials of special alloys so far as the composition of the alloy requires or permits special drawing methods or sequences
• CPC Class Codes: B21C 1/02 Drawing metal wire or like flexible metallic material by drawing machines or apparatus in which the drawing action is effected by drums
• CPC Class Codes: B22D 11/0602 formed by a casting wheel and belt, e.g. Properzi-process
• CPC Class Codes: H01B 1/023 Alloys based on aluminium
• CPC Class Codes: H01B 1/026 Alloys based on copper
• CPC Class Codes: H01B 13/0036 Details
• CPC Class Codes: H01B 13/148 Selection of the insulating material therefor
• CPC Class Codes: H01B 3/441 from alkenes
• CPC Class Codes: H01B 7/295 using material resistant to flame

Abstract

The invention relates to an elongated electrically conductive copper-aluminum bimetal element, a cable comprising at least one such elongated electrically conductive element, a process for preparing said elongated electrically conductive element and said cable, and a device comprising such an electric cable and at least one metal connector.

Claims

1. An elongated electrically conductive element comprising:

an aluminum or aluminum alloy core; and

a copper or copper alloy layer surrounding said aluminum or aluminum alloy core,

wherein the copper or copper alloy layer represents a volume greater than 30% of the volume of the elongated electrically conductive element, and

wherein said element is capable of being obtained according to a process comprising at least one step i) of forming a copper of copper alloy layer around an aluminum or aluminum alloy core by continuous casting.

2. The element as claimed in claim 1, wherein the copper layer represents from 40% to 80% by volume, of the volume of the elongated electrically conductive element.

3. The element as claimed in claim 1, wherein the copper or copper alloy layer is the outermost layer of the elongated electrically conductive element.

4. The element as claimed in claim 1, wherein said element has an external diameter ranging from 0.01 to 30 mm.

5. The element as claimed in claim 1, wherein the copper or copper alloy layer is directly in contact with the aluminum or aluminum alloy core.

6. The element as claimed in claim 1, wherein the aluminum content of the aluminum alloy is at least 95.00% by weight.

7. The element as claimed in claim 1, wherein the copper content of the copper alloy is at least 95.00% by weight.

8. The element as claimed in claim 1, wherein said element has a reduction of at most 20%, in newtons, of the mechanical strength of the terminals in a tensile test, when it is subjected to an exposure to a salt spray of at least 50 h.

9. An electric cable, comprising at least one elongated electrically conductive element as defined in claim 1 and at least one polymer layer surrounding said elongated electrically conductive element.

10. The electric cable as claimed in claim 9, wherein the polymer layer is an electrically insulating layer.

11. The electric cable as claimed in claim 9, wherein the polymer layer comprises a polymer material chosen from crosslinked and non-crosslinked polymers, and polymers of inorganic type and of organic type.

12. The electric cable as claimed in claim 9, wherein the polymer layer does not comprise halogenated compounds and the cable is a HFFR cable.

13. A device comprising:

an electric cable having at least one elongated electrically conductive element as defined in claim 1, and at least one polymer layer surrounding said elongated electrically conductive element; and

at least one metal connector,

wherein said metal connector is connected to said at least one elongated electrically conductive element.

14. The element as claimed in claim 1, wherein the metals used during step i) of forming a copper or copper alloy layer around an aluminum or aluminum alloy core by continuous casting are:

for the copper or the copper alloy, in the liquid state, and

for the aluminum or the aluminum alloy, in the liquid or solid state.

15. The element as claimed in claim 1, wherein the aluminum or the aluminum alloy is in the solid state, and

step i) is a step i-1) during which copper or a copper alloy in the liquid state is cast on aluminum or an aluminum alloy in the solid state, or aluminum or aluminum alloy in the solid state is immersed in copper or a copper alloy in the liquid state.

16. The element as claimed in claim 1, wherein the aluminum is in the liquid state, and step i) is a step i-2) during which a hollow element made of copper or of copper alloy is preformed from copper or a copper alloy in the liquid state;

then said hollow element is cooled;

then the hollow element is filled with aluminum or an aluminum alloy in the liquid state;

then the assembly obtained is cooled.

17. An elongated electrically conductive element comprising:

an aluminum or aluminum alloy core; and

a copper or copper alloy layer surrounding said aluminum or aluminum alloy core,

wherein the copper or copper alloy layer represents from 45% to 70% by volume of the volume of the elongated electrically conductive element.