SiCN compositions and methods

• US 20040206008A1
• Filed: 03/22/2004
• Published: 10/21/2004
• Est. Priority Date: 07/16/2001
• Status: Abandoned Application

• Current Assignee: Chien-Min Sung
• Original Assignee: Chien-Min Sung
• Inventors: Sung, Chien-Min
• Application Number:
  US10/807,503
• Publication Number:
  US 20040206008A1
• Time in Patent Office: Days
• US Class Current: 51/307
• CPC Class Codes: C01B 21/0828 Carbonitrides or oxycarbonitrides of metals, boron or silicon
• CPC Class Codes: C09K 3/1427 obtained by division of a mass agglomerated by melting, at least partially, e.g. with a binder
• CPC Class Codes: C09K 3/1436 Composite particles, e.g. coated particles
• CPC Class Codes: C23C 10/02 Pretreatment of the material to be coated C23C10/04 takes precedence
• CPC Class Codes: C23C 26/02 applying molten material to the substrate
• CPC Class Codes: C23C 8/02 Pretreatment of the material to be coated C23C8/04 takes precedence
• CPC Class Codes: C30B 11/00 Single-crystal growth by normal freezing or freezing under temperature gradient, e.g. Bridgman-Stockbarger method C30B13/00, C30B15/00, C30B17/00, C30B19/00 take precedence; under a protective fluid C30B27/00
• CPC Class Codes: C30B 11/12 Vaporous components, e.g. vapour-liquid-solid-growth
• CPC Class Codes: C30B 29/36 Carbides
• CPC Class Codes: C30B 29/38 Nitrides

Abstract

The present invention provides a method for making a superabrasive composite material having the general formula Si_xC_yN_z, and tools containing such a material. In one aspect, vapor forms of Si, C, and N atoms are deposited onto a molten metal catalyst and solid Si_xC_yN_z is precipitated therefrom. The composite Si_xC_yN_z materials have an interatomic structure substantially like that of silicon nitride. Such Si_xC_yN_z materials can be used to form superabrasive particles, fibers, or coatings for various tools.

Claims

1. A method of making a superabrasive composite material having the general formula Si_xC_yN_z, comprising the steps of:

a) depositing a metal-containing catalyst on a substrate;

b) heating the metal-containing catalyst to a temperature sufficient to melt the metal-containing catalyst; and

c) depositing Si, C, and N atoms from a vapor source onto the molten metal-containing catalyst to produce a composite Si_xC_yN_z material having an interatomic structure substantially like that of silicon nitride.

2. The method of claim 1, wherein the Si and C atoms have a Si to C atomic ratio of less than about 1:

4 in the vapor source.

3. The method of claim 1, wherein the N atoms are present at from about 2 to about 8 times the Si and C atoms combined.

4. The method of claim 1, wherein the superabrasive composite material has a hexagonal unit cell substantially throughout the crystal structure.

5. The method of claim 1, wherein the superabrasive composite material is substantially free of silicon-carbide bonds.

6. The method of claim 1, wherein the superabrasive composite has a molecular formula of (Si_VC_W)₃N₄, such that V+W is about 1.

7. The method of claim 1, wherein X is less than or equal to Y and Z is greater than X or Y.

8. The method of claim 7, wherein X is less than Y.

9. The method of claim 1, wherein Z is greater than X+Y.

10. The method of claim 9, wherein X is less than half of Y.

11. The method of claim 1, wherein the compound has a formula of (Si,C)₃N₄

12. The method of claim 1, wherein the substrate contains an element selected from the group consisting of Si, C, N, W, Ta, Ti, as well as compounds, alloys, and mixtures thereof.

13. The method of claim 12, wherein the substrate is Si (111).

14. The method of claim 12, wherein the substrate contains C.

15. The method of claim 1, wherein the substrate is a metal.

16. The method of claim 15, wherein the metal is an alloy of nickel, cobalt, and iron.

17. The method of claim 1, wherein the metal-containing catalyst includes a metal salt.

18. The method of claim 17, wherein the metal salt includes a halide.

19. The method of claim 18, wherein the halide is a member selected from the group consisting of fluorine, chlorine, bromine, iodine, astatine, ions thereof, and mixtures thereof.

20. The method of claim 1, wherein the metal-containing catalyst consists of a metal and alloys thereof.

21. The method of claim 20, wherein the metal is a member selected from the group consisting of gold, silver, platinum, copper, nickel, iron, cobalt, chromium, manganese, zinc, alloys thereof, and mixtures thereof.

22. The method of claim 21, wherein the metal catalyst is gold.

23. The method of claim 1, wherein the metal-containing catalyst is fixed to the substrate.

24. The method of claim 1, wherein the vapor source includes a Si compound, a C compound, and an N compound, each of which contains no more than single bonding arrangements.

25. The method of claim 24, wherein at least one of the Si, C, and N compounds is either a hydride or a halide.

26. The method of claim 24, wherein each of the Si, C, and N compounds is either a hydride or a halide.

27. The method of claim 24, wherein the Si compound is SH₄, the C compound is CH₄, and the N compound is NH₃.

28. The method of claim 24, wherein the Si compound is SCl₄, the C compound is CCl₄, and the N compound is NCl₃.

29. The method of claim 1, wherein the composite material is produced at a rate of from about 20 μ

m/hr to about 2 mm/hr.

30. The method of claim 1, wherein the substrate is a tool body.

31. The method of claim 30, wherein the tool body is a cutting tool body.

32. The method of claim 30, wherein the tool body is a light emitting diode.

33. The method of claim 1, wherein the superabrasive composite material is in the form of a member selected from the group consisting of hexagonal column, fiber, grit, film, and combinations thereof.

34. The method of claim 33, wherein the composite material is in the form of grits having a size greater than about 40 micrometers.

35. A method of making a superabrasive composite material having the general formula Si_xC_yN_z, comprising the steps of:

a) depositing a metal-containing a catalyst selected from the group consisting of gold, silver, platinum, copper, nickel, iron, cobalt, alloys thereof, and mixtures thereof, on a substrate;

b) heating the metal-containing catalyst to a temperature of from about 800°

C. to about 1000°

C., thereby melting the metal-containing catalyst;

c) decomposing single bond compounds containing Si, C, and N atoms from a vapor source; and

d) depositing the Si, C, and N atoms from the single bond compounds onto the molten metal-containing catalyst, to produce a composite Si_xC_yN_z material having an interatomic structure substantially like that of silicon nitride, such that X is less than half of Y and Z is greater than X or Y.

36. A method for making a Si_xC_yN_z compound comprising:

a) depositing Si, C and N elements from a vapor source into a molten metal catalyst; and

b) precipitating the Si_xC_yN_z compound out of the molten metal catalyst.

37. The method of claim 36, wherein said vapor source includes Si, C and N single bond compounds.

38. The method of claim 36, wherein the Si_xC_yN_z compound has an interatomic structure substantially like that of silicon nitride.

39. The method of claim 36, wherein X is less than half of Y and Z is greater than X or Y.

40. A superabrasive composite material having the general formula Si_xC_yN_z such that X is less than half of Y and is substantially free of silicon-carbide bonds.

41. The composite material of claim 40, further having an interatomic structure substantially like that of silicon nitride.

42. The composite material of claim 40, wherein the composite material has a molecular formula of (Si_VC_W)₃N₄, such that V+W is about 1.

43. The composite material of claim 40, wherein the composite material is in the form of a member selected from the group consisting of hexagonal column, fiber, grit, film, and combinations thereof.

44. The composite material of claim 40, wherein X is from about 0.05Y to about 0.35Y.

45. A superabrasive composite material having the general formula Si_xC_yN_z such that X is from about 0.05Y to about 0.35Y and is substantially free of silicon-carbide bonds.