Composite material containing tungsten and bronze

• US 7,232,473 B2
• Filed: 10/16/2002
• Issued: 06/19/2007
• Est. Priority Date: 10/16/2001
• Status: Expired due to Fees

• Current Assignee: Elliott Cartridge Company (Canada), Ltd.
• Original Assignee: International Non-Toxic Composites
• Inventors: Elliott, Kenneth H.
• Primary Examiner(s): King; Roy
• Assistant Examiner(s): KESSLER, CHRISTOPHER S
• Application Number:
  US10/270,526
• Publication Number:
  US 20030161751A1
• Time in Patent Office: 1,707 Days
• Field of Search: 102/517, 102/506, 419/36, 419/38, 752/47, 752/48, 752/45
• US Class Current: 75/245
• CPC Class Codes: A01K 95/005 Sinkers not containing lead
• CPC Class Codes: B22F 1/09 Mixtures of metallic powders
• CPC Class Codes: B22F 1/10 Metallic powder containing lubricating or binding agents; Metallic powder containing organic material
• CPC Class Codes: B22F 1/148 Agglomerating
• CPC Class Codes: B22F 2998/00 Supplementary information concerning processes or compositions relating to powder metallurgy
• CPC Class Codes: B22F 2998/10 Processes characterised by the sequence of their steps
• CPC Class Codes: B22F 3/10 Sintering only
• CPC Class Codes: B22F 3/1025 not by heating only
• CPC Class Codes: B22F 3/26 Impregnating making ferrous alloys by impregnation C22C33/0242
• CPC Class Codes: C22C 1/0425 Copper-based alloys
• CPC Class Codes: C22C 1/045 Alloys based on refractory metals
• CPC Class Codes: F42B 12/74 of the core or solid body
• CPC Class Codes: F42B 7/046 Pellets or shot therefor

Abstract

High-density composite materials comprising tungsten and bronze are useful as lead replacements in the production of ammunition, weights and other high density articles. The composition of the composite, articles manufactured using the composite, and a process for making the composite are disclosed.

Claims

1. A composite consisting essentially of liquid phase sintered tutgsten particles in a copper/tin bronze matrix.

2. The composite of claim 1, wherein the tungsten is present in the composite in an amount of from 40% to 85% tungsten by weight of the composite.

3. The composite of claim 2, wherein the tungsten is present in the composite in an amount of from 50% to 55% tungsten by weight of the composite.

4. The composite of claim 1, wherein the bronze consists essentially of 80% to 95% copper by weight of the bronze, the balance being tin.

5. The composite of claim 4, wherein the bronze consists essentially of copper and tin in a ratio of about 9:

1 by weight of the bronze.

6. The composite of claim 1, consisting essentially of 52% tungsten and 48% pre-alloyed copper/tin bronze by weight of the composite, the bronze consisting essentially of copper and tin in a ratio of about 9:

1 by weight of the bronze.

7. The composite of claim 1, wherein the tungsten has a mean particle size of from 0.5 to 50 μ

m and the bronze has a mean particle size of less than 100 μ

m.

8. The composite of claim 7, wherein the tungsten has a mean particle size of from 1 to 20 μ

m and the bronze has a mean particle size of less than 50 μ

m.

9. The composite of claim 1, wherein the composite consists essentially of from 45% to 85% tungsten by weight of the composite, and the bronze consists essentially of 80% to 95% copper and balance tin by weight of the bronze.

10. An article comprising a composite as defined in claim 9.

11. An article comprising a composite as defined in claim 1.

12. A composite consisting essentially of liquid phase sintered tungsten particles in a copper/tin bronze matrix and an amount of iron, wherein said amount of iron increases the density of said composite relative to a composite in the absence of iron.

13. The composite of claim 12, wherein the tungsten is present in the composite in an amount of from 40% to 85% tungsten by weight of the composite.

14. The composite of claim 13, wherein the tungsten is present in the composite in an amount of from 50% to 55% tungsten by weight of the composite.

15. The composite of claim 12, wherein the bronze consists essentially of 80% of 95% copper by weight of the bronze, the balance being tin.

16. The composite of claim 15, wherein the bronze consists essentially of copper and tin in a ratio of about 9:

1 by weight of the bronze.

17. The composite of claim 12, consisting essentially of 52% W, 47.2% pre-alloyed copper/tin bronze, and 0.8% Fe by weight of the composite, the bronze consisting essentially of copper and tin in a ratio of about 9:

1 by weight of the bronze.

18. The composite of claim 12, wherein the tungsten has a mean particle size of from 0.5 to 50 μ

m and the bronze has a mean particle size of less than 100 μ

m.

19. The composite of claim 18, wherein the tungsten has a mean particle size of from 1 to 20 μ

m and the bronze has a mean particle size of less than 50 μ

m.

20. The composite of claim 12, wherein the composite consists essentially of from 40% to 85% tungsten by weight of the composite, and the bronze consists essentially of 80% to 95% copper and balance tin by weight of the bronze.

21. An article comprising a composite as defined in claim 12.

22. An article comprising a composite as defined in claim 20.

23. A composite consisting essentially of liquid phase sintered tungsten particles in a copper/tin bronze matrix, sintered at a temperature of at least about 600 C., the composite having no visible voids in its microstructure at 1000 times optical magnification, the composite having a strength under compression of at least about 155 MPa.

24. The composite of claim 23, wherein the tungsten is present in the composite in an amount of from 40% to 85% tungsten by weight of the composite.

25. The composite of claim 24, wherein the tungsten is present in the composite in an amount of from 50% to 55% tungsten by weight of the composite.

26. The composite of claim 23, wherein the bronze consists essentially of 80% to 95% copper and balance tin, by weight of the bronze.

27. The composite of claim 23, wherein the bronze consists essentially of copper and tin in a ratio of about 9:

1 by weight of the bronze.

28. The composite of claim 23, wherein the composite consists essentially of from 40% to 85% tungsten by weight of the composite, and the bronze consists essentially of 80% to 95% copper and balance tin by weight of the bronze.

29. The composite of claim 23, wherein the composite consists essentially of 52% tungsten and 48% bronze by weight of the composite, the bronze consisting essentially of copper and tin in a ratio of about 9:

1 by weight of the bronze.

30. The composite of claim 23, further including an amount of iron, wherein said amount of iron increases the density of said composite relative to a composite in the absence of iron.

31. The composite of claim 23, wherein the tungsten has a mean particle size of from 0.5 to 50 μ

m and the bronze has a mean particle size of less than 100 μ

m.

32. The composite of claim 31, wherein the tungsten has a mean particle size of from 1 to 20 μ

m and the bronze has a mean particle size of less than 50 μ

m.

33. The composite of claim 23, wherein the temperature is in the range from about 800–

1100 C.

34. The composite of claim 33, wherein the strength under compression is at least about 460 MPa.

35. An article comprising a composite as defined in claim 23.

36. An article comprising a composite as defined in claim 28.