Electrical contact alloy for vacuum contactors

• US 10,468,205 B2
• Filed: 12/13/2016
• Issued: 11/05/2019
• Est. Priority Date: 12/13/2016
• Status: Active Grant

• Current Assignee: Eaton Intelligent Power Limited (Eaton Corporation PLC.)
• Original Assignee: Eaton Intelligent Power Limited (Eaton Corporation PLC.)
• Inventors: Campbell, Louis Grant, Balasubramanian, Ganesh Kumar, Rosenkrans, Benjamin Alex
• Primary Examiner(s): Nguyen, Truc T
• Assistant Examiner(s): Bolton, William A
• Application Number:
  US15/377,258
• Publication Number:
  US 20180166225A1
• Time in Patent Office: 1,057 Days
• Field of Search: 218123, 218130, 218132, 200266, 75247
• CPC Class Codes: B22F 1/09 Mixtures of metallic powders
• CPC Class Codes: B22F 2003/1051 by electric discharge
• CPC Class Codes: B22F 2003/247 Removing material: carving, cleaning, grinding, hobbing, honing, lapping, polishing, milling, shaving, skiving, turning the surface
• CPC Class Codes: B22F 2009/041 by mechanical alloying, e.g. blending, milling
• CPC Class Codes: B22F 2009/043 by ball milling
• CPC Class Codes: B22F 2301/10 Copper
• CPC Class Codes: B22F 2301/20 Refractory metals
• CPC Class Codes: B22F 2302/10 Carbide
• CPC Class Codes: B22F 2998/10 Processes characterised by the sequence of their steps
• CPC Class Codes: B22F 3/1035 Liquid phase sintering
• CPC Class Codes: B22F 3/105 by using electric current other than for infrared radiant energy, laser radiation or plasma B22F3/11 takes precedence; by ultrasonic bonding B22F3/115 takes precedence
• CPC Class Codes: B22F 3/15 Hot isostatic pressing
• CPC Class Codes: B22F 3/16 in successive or repeated steps
• CPC Class Codes: B22F 3/24 After-treatment of workpieces or articles B22F3/1146 takes precedence
• CPC Class Codes: B22F 9/04 starting from solid material, e.g. by crushing, grinding or milling C22C1/1084 takes precedence; crushing, grinding or milling, in general, see the relevant subclasses, e.g. B02C
• CPC Class Codes: C22C 30/02 containing copper
• CPC Class Codes: C22C 32/0052 only carbides
• CPC Class Codes: C22C 9/00 Alloys based on copper
• CPC Class Codes: H01B 1/026 Alloys based on copper
• CPC Class Codes: H01H 1/0203 specially adapted for vacuum switches
• CPC Class Codes: H01H 1/0206 : containing as major components Cu and Cr
• CPC Class Codes: H01H 1/0233 : and containing carbides
• CPC Class Codes: H01H 1/025 : having copper as the basic material
• CPC Class Codes: H01H 1/027 : containing carbon particles or fibres

Abstract

An improved electrical contact alloy, useful for example, in vacuum interrupters used in vacuum contactors is provided. The contact alloy according to the disclosed concept comprises copper particles and chromium particles present in a ratio of copper to chromium of 2:3 to 20:1. The electrical contact alloy also comprises particles of a carbide, which reduces the weld break strength of the electrical contact alloy without reducing its interruption performance.

Claims

1. An electrical contact alloy comprising:

a homogenous mixture of copper particles;

chromium particles;

wherein the copper particles to chromium particles relative to each other have a weight ratio of 55;

45;

particles of a carbide present in an amount ranging from 0 to 73 wt. % relative to the alloy; and

sintering activation elements present in an amount less than 0.5 wt. % to increase density.

2. The alloy recited in claim 1 wherein the carbide is selected from the group of silicon carbides and metal carbides.

3. The alloy recited in claim 2 wherein the metal carbides are selected from the group consisting of tungsten carbide, molybdenum carbide, vanadium carbide, chromium carbide, niobium carbide, and tantalum carbide, titanium carbide, and hafnium carbide.

4. The alloy recited in claim 1 wherein the sintering activation elements are selected from the group consisting of cobalt, nickel, nickel-iron, and iron aluminide.

5. The alloy recited in claim 1 wherein the carbide is tungsten carbide.

6. The alloy recited in claim 1 wherein the carbide is molybdenum carbide.

7. The alloy recited in claim 1 wherein the carbide is vanadium carbide.

8. The alloy recited in claim 1 wherein the carbide is niobium carbide.

9. The alloy recited in claim 1 wherein the carbide is tantalum carbide.

10. The alloy recited in claim 1 wherein the carbide is chromium carbide.

11. The alloy recited in claim 1 wherein the carbide is titanium carbide.

12. The alloy recited in claim 1 wherein the carbide is hafnium carbide.

13. The alloy recited in claim 1 wherein the chromium is present in an amount ranging from 5 to 60 wt. % relative to copper, the balance being copper.

14. An electrical contact for use in a vacuum interrupter comprising:

an electrically conductive contact member formed from an alloy comprised of;

a homogenous mixture of copper particles and chromium particles, wherein the copper particles to chromium particles have a weight ratio relative to each other of 55;

45;

particles of a carbide present in an amount ranging from 0 to 73 wt. % relative to the alloy; and

sintering activation elements present in an amount less than 0.5 wt. % to increase density.

15. The contact recited in claim 14 wherein the carbide is selected from the group consisting of silicon carbide, tungsten carbide, molybdenum carbide, vanadium carbide, chromium carbide, niobium carbide, tantalum carbide, titanium carbide, and hafnium carbide.

16. An electrical contact alloy comprising:

a homogenous mixture of copper particles;

chromium particles;

wherein the copper particles to chromium particles have a weight ratio relative to each other ranging from 2;

3 to 20;

1 by weight;

particles of a carbide present in an amount ranging from 0 to 73 wt. % relative to the alloy; and

,

sintering activation elements present in an amount less than 0.5 wt. % to increase density.

17. The alloy recited in claim 16 wherein the sintering activation elements are selected from the group consisting of cobalt, nickel, nickel-iron, and iron aluminide.

18. The alloy recited in claim 16 wherein the carbide is selected from the group of silicon carbides and metal carbides.

19. The alloy recited in claim 18 wherein the metal carbides are selected from the group consisting of tungsten carbide, molybdenum carbide, vanadium carbide, chromium carbide, niobium carbide, and tantalum carbide, titanium carbide, and hafnium carbide.

20. The alloy recited in claim 16 wherein the chromium is present in an amount ranging from 5 to 60 wt. % relative to copper, the balance being copper.