Composite conductor and electric wire using the same

Patent metadata

Field	Value
Publication number	US-9293232-B2
Application number	US-201214362868-A
Country	US
Kind code	B2
Filing date	Dec 6, 2012
Priority date	Dec 7, 2011
Publication date	Mar 22, 2016
Grant date	Mar 22, 2016

Abstract

A composite conductor 10 , including an internal layer 11 having a conductive material A, the conductive material A having fatigue strength of at least 150 MPa after being subjected to 10 6 cycles of cyclic loading in a fatigue test, and an external layer 12 having a conductive material B, the external layer coating the internal layer 11 , the conductive material B having tensile strength higher than that of the conductive material A, the tensile strength being at least 250 MPa, in which the composite conductor 10 has fracture resistance to a sudden load and impact as well as bending durability.

First claim

The invention claimed is:

1. A composite conductor, comprising:
an internal layer comprising a conductive material A, the conductive material A having fatigue strength of at least 150 MPa after being subjected to 10 6 cycles of cyclic loading in a fatigue test; and
an external layer comprising a conductive material B, the external layer coating the internal layer, the conductive material B having tensile strength higher than that of the conductive material A, the tensile strength being at least 250 MPa;
wherein the composite conductor has fracture resistance to a sudden load and impact as well as bending durability.

2. The composite conductor according to claim 1 ,
wherein the conductive material A comprises a metal texture including (i) a crystal grain of aluminium or an aluminium-based alloy, the crystal grain having an average grain size of 2 μm or less, and (ii) a nanoparticle C existing in a grain boundary between the crystal grains, and
wherein the conductive material B comprises a metal texture including a crystal grain of copper or a copper-based alloy, the crystal grain having an average grain size of 2 μm or less.

3. The composite conductor according to claim 2 ,
wherein the nanoparticle C comprises any one of fullerene, carbon nanotube, a silicon nanoparticle, a transition metal nanoparticle, and a compound nanoparticle including a compound of a metal forming the conductive material A, the nanoparticle C being 0.1 mass % or more but not exceeding 20 mass %.

4. The composite conductor according to claim 2 ,
wherein the nanoparticle C is a nanoscale aluminium-scandium precipitate, the nanoscale precipitate being 0.1 mass % or more but not exceeding 1 mass %.

5. The composite conductor according to claim 2 ,
wherein the conductive material A comprises the aluminium-based alloy and the aluminium-based alloy further comprises 0.1 mass % or more but not exceeding 0.2 mass % of zirconium.

6. The composite conductor according to claim 2 ,
wherein the metal texture of the conductive material A comprises 20% or more of the crystal grains by cross sectional area with a grain size of 1 μm or less.

7. The composite conductor according to claim 2 ,
wherein the conductive material B comprises the copper-based alloy, and the copper-based alloy is any one of a copper silver alloy, a copper tin alloy, and a copper nickel alloy.

8. The composite conductor according to claim 1 ,
wherein the conductive material A comprises a metal texture including a crystal grain of copper, the crystal grain having an average grain size of 2 μm or less,
wherein the conductive material B comprises a metal texture including a crystal grain of a copper-based alloy, the crystal grain having an average grain size of 2 μm or less, and
wherein a strength ratio σ B /σ A of tensile strength σ B of the conductive material B to tensile strength σ A of the conductive material A is 1.6 or more.

9. The composite conductor according to claim 8 ,
wherein 0.1 mass % or more but not exceeding 20 mass % of a nanoparticle D exists in a grain boundary of the crystal grains in the metal texture forming the conductive material B.

10. The composite conductor according to claim 9 ,
wherein the nanoparticle D comprises any one of fullerene, carbon nanotube, a silicon nanoparticle, a transition metal nanoparticle, and a compound nanoparticle comprising a compound of a metal forming the conductive material B.

11. An electric wire made of the composite conductor according to claim 1 , comprising:
a composite strand having a diameter of 0.05 mm or more but not exceeding 0.5 mm,
wherein the electric wire is used as an electric wire for wiring a drive member for a robot.

12. A composite conductor, comprising:
an internal layer comprising a conductive material A, the conductive material A having fatigue strength of at least 150 MPa after being subjected to 10 6 cycles of cyclic loading in a fatigue test; and
an external layer comprising a conductive material B, the external layer coating the internal layer, the conductive material B having tensile strength higher than that of the conductive material A, the tensile strength being at least 150 MPa;
wherein the composite conductor has bending durability.

13. The composite conductor according to claim 12 ,
wherein the conductive material A comprises a metal texture including (i) a crystal grain of aluminium, the crystal grain having an average grain size of 2 μm or less, and (ii) a nanoscale aluminium-scandium precipitate existing in a grain boundary between the crystal grains, the nanoscale precipitate being 0.1 mass % or more but not exceeding 1 mass % and
wherein the conductive material B comprises a metal texture including a crystal grain of silver or a silver-based alloy, the crystal grain having an average grain size of 2 μm or less.

14. The composite conductor according to claim 12 ,
wherein the conductive material A comprises a metal texture including a crystal grain of copper or a copper-based alloy, the crystal grain having an average grain size of 2 μm or less, and
wherein the conductive material B comprises a metal texture including a crystal grain of silver or a silver-based alloy, the crystal grain having an average grain size of 2 μm or less.

15. The composite conductor according to claim 12 ,
wherein the conductive material A comprises a metal texture including (i) a crystal grain of aluminium or an aluminium-based alloy, the crystal grain having an average grain size of 2 μm or less, and (ii) a nanoparticle C existing in a grain boundary between the crystal grains,
wherein the conductive material B comprises a metal texture including a crystal grain of silver or a silver-based alloy, the crystal grain having an average grain size of 2 μm or less, and
wherein the nanoparticle C comprises any one of fullerene, carbon nanotube, a silicon nanoparticle, a transition metal nanoparticle, and a compound nanoparticle including a compound of a metal forming the conductive material A, the nanoparticle C being 0.1 mass % or more but not exceeding 20 mass %.

16. An electric wire made of the composite conductor according to claim 12 , comprising:
a composite strand having a diameter of 0.05 mm or more but not exceeding 0.5 mm,
wherein the electric wire is used as an electric wire for wiring an automobile or an aircraft.

Assignees

• Dyden Corp
• Fukuoka Prefecture
• Univ Kumamoto Nat Univ Corp
• Nat L University Corp Kumamoto University

Inventors

• In Hiroyuki
• ANNOU Fumiyo
• Matsunaga Daisuke
• KITAHARA Hiromoto
• Ando Shinji
• TSUSHIDA Masayuki
• Ogawa Toshifumi

Classifications

• C22C5/06

  Alloys based on silver · CPC title

• H01B1/026 Primary

  Alloys based on copper · CPC title

• C22F1/00

  Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working (apparatus for mechanical working of metal B21, B23, B24) · CPC title

• C22C9/00

  Alloys based on copper · CPC title

• C22C5/08

  with copper as the next major constituent · CPC title