High volume density polycrystalline diamond with working surfaces depleted of catalyzing material

• US 20020034631A1
• Filed: 08/30/2001
• Published: 03/21/2002
• Est. Priority Date: 09/20/2000
• Status: Active Grant

• Current Assignee: Reedhycalog UK (National Oilwell Varco Incorporated)
• Original Assignee: Reedhycalog UK (National Oilwell Varco Incorporated)
• Inventors: Griffin, Nigel Dennis, Hughes, Peter Raymond
• Granted Patent: US 6,544,308 B2
• Time in Patent Office: Days
• US Class Current: 428/332
• CPC Class Codes: C04B 37/021 in a direct manner, e.g. direct copper bonding [DCB]
• CPC Class Codes: E21B 10/567 with preformed cutting elements mounted on a distinct support, e.g. polycrystalline inserts
• CPC Class Codes: Y10T 407/27 comprising tool of specific chemical composition
• CPC Class Codes: Y10T 428/12493 Composite; i.e., plural, adjacent, spatially distinct metal components [e.g., layers, joint, etc.]
• CPC Class Codes: Y10T 428/12625 Free carbon containing component
• CPC Class Codes: Y10T 428/24942 including components having same physical characteristic in differing degree
• CPC Class Codes: Y10T 428/26 Web or sheet containing structurally defined element or component, the element or component having a specified physical dimension
• CPC Class Codes: Y10T 428/265 1 mil or less
• CPC Class Codes: Y10T 428/30 Self-sustaining carbon mass or layer with impregnant or other layer

Abstract

Disclosed is a polycrystalline diamond or diamond-like element with greatly improved wear resistance without loss of impact strength. These elements are formed with a binder-catalyzing material in a high-temperature, high-pressure (HTHP) process. The PCD element has a body with a plurality of bonded diamond or diamond-like crystals forming a continuous diamond matrix that has a diamond volume density greater than 85%. Interstices among the diamond crystals form a continuous interstitial matrix containing a catalyzing material. The diamond matrix table is formed and integrally bonded with a metallic substrate containing the catalyzing material during the HTHP process. The diamond matrix body has a working surface, where a portion of the interstitial matrix in the body adjacent to the working surface is substantially free of the catalyzing material, and the remaining interstitial matrix contains the catalyzing material. Typically, less than about 70% of the body of the diamond matrix table is free of the catalyzing material.

Claims

1. A PCD element comprising a body of bonded diamonds with a working surface integrally formed with a metallic substrate, the body having at least an 85% by volume diamond density, wherein a first volume of the body remote from the working surface contains a catalyzing material, a second volume of the body adjacent to the working surface is substantially free of the catalyzing material.

2. The PCD element of claim 1, wherein the second volume extends to a depth of at least about 0.1 mm from the working surface.

3. The PCD element of claim 2, wherein the second volume extends to a depth of between about 0.2 mm and 0.3 mm from the working surface.

4. The PCD element of claim 1, wherein the first volume of the body contacts the substrate and has an average thickness greater than 0.15 mm.

5. The PCD element of claim 1, wherein a majority of the catalyzing material remaining in the second volume of the body adheres to surfaces of diamond crystals.

6. The PCD element of claim 1, wherein an amount of catalyzing material within the second volume of the body continuously decreases with distance from the first volume.

7. The PCD element of claim 1 wherein the first volume comprises more than 30% of the body remote from the working surface.

8. The PCD element of claim 7 wherein the substrate is tungsten carbide with an iron group binder material.

9. The PCD element of claim 1 comprising a preform cutting element having a facing table and a cutting surface, wherein the working surface comprises a portion of the cutting surface.

10. The PCD element of claim 9, wherein the cutting element is mounted upon a cutting face of a fixed cutter rotary drill bit.

11. The PCD element of claim 9, wherein the cutting element is mounted upon a body of a rolling cutter drill bit.

12. The PCD element of claim 1, wherein the body comprises diamond crystals and an interstitial matrix, and wherein the part of the interstitial matrix located within the second volume is substantially free of the catalyzing material, and the interstitial matrix where the body contacts the substrate contains the catalyzing material and has an average thickness greater than 0.15 mm.

13. The PCD element of claim 12, wherein the second volume extends to a depth of at least about 0.1 mm from the working surface.

14. The PCD element of claim 13, wherein the second volume extends to a depth of between about 0.2 mm and 0.3 mm from the working surface.

15. The PCD element of claim 12 wherein the first volume comprises more than 30% of the body remote from the working surface.

16. The PCD element of claim 12, wherein a majority of diamond crystals located within the second volume of the body have a surface which is substantially free of catalyzing material.

17. The PCD element of claim 12, wherein a majority of the catalyzing material remaining in the second volume of the body adheres to surfaces of the diamond crystals.

18. The PCD element of claim 12, wherein the diamond crystals in the second volume remote from the first volume have less catalyzing material adhering to their surfaces than the diamond crystals in the second volume which are adjacent to the first volume.

19. The PCD element of claim 12, wherein an amount of catalyzing material within the second volume of the body continuously decreases with distance from the first volume.

20. The PCD element of claim 14 comprising a preform cutting element having a facing table and a cutting surface, wherein the working surface comprises a portion of the cutting surface.

21. The PCD element of claim 20, wherein the cutting element is mounted upon a cutting face of a fixed cutter rotary drill bit.

22. The PCD element of claim 20, wherein the cutting element is mounted upon a body of a rolling cutter drill bit.

23. The PCD element of claim 12, comprising a cutting element with a cutting surface adapted for use as a cutting insert in a machining operation, wherein the working surface comprises a portion of the cutting surface.

24. The PCD element of claim 12, comprising a drawing die, wherein the working surface comprises a portion of the drawing die contact surface.

25. The PCD element of claim 12 wherein the substrate is tungsten carbide with an iron group binder material.

27. The preform cutting element of claim 26, wherein the cutting element is mounted upon a cutting face of a fixed cutter rotary drill bit.

28. The preform cutting element of claim 26, wherein the cutting element is mounted upon a body of a rolling cutter drill bit.

29. The preform cutting element of claim 26, comprising a cutting element with the cutting surface adapted for use as a cutting insert in a machining operation.

30. The preform cutting element of claim 26 wherein the substrate is tungsten carbide with an iron group binder material.

26. A preform cutting element comprising a body of a superhard polycrystalline material comprising a plurality of partially bonded superhard crystals integrally formed with a metallic substrate, a plurality of interstitial regions among the superhard crystals and a catalyzing material, the body having at least an 85% by volume diamond density and a cutting surface, wherein the interstitial regions adjacent to at least a portion of the cutting surface are substantially free of the catalyzing material and the interstitial regions where the body contacts the substrate contain the catalyzing material and have an average thickness greater than 0.15 mm.

31. A PCD element comprising a diamond containing body integrally formed with a metallic substrate, the body having at least an 85% by volume diamond density and an interstitial matrix, wherein the interstitial matrix in the body adjacent to a working surface is substantially free of the catalyzing material, and the interstitial matrix where the body contacts the substrate contains the catalyzing material and has an average thickness greater than 0.15 mm.

32. The PCD element of claim 31, wherein the interstitial matrix in the body adjacent to the working surface is substantially free of the catalyzing material to a depth of at least about 0.1 mm from the working surface.

33. The PCD element of claim 32, wherein the interstitial matrix in the body adjacent to the working surface is substantially free of the catalyzing material to a depth of between about 0.2 mm and 0.3 mm from the working surface.

34. The PCD element of claim 31, wherein the interstitial matrix in the body adjacent to the working surface of the body has a diamond density higher than elsewhere in the body.

35. The PCD element of claim 31, wherein a majority of the catalyzing material remaining in the interstitial matrix in the body adjacent to the working surface of the body adheres to surfaces of diamond crystals.

36. The PCD element of claim 31, wherein an amount of catalyzing material within the interstitial matrix in the body adjacent to the working surface of the body continuously decreases with distance from the remaining interstitial matrix.

37. The PCD element of claim 31 comprising a preform cutting element having a facing table and a cutting surface, wherein the working surface comprises a portion of the cutting surface.

38. The PCD element of claim 37, wherein the cutting element is mounted upon a cutting face of a fixed cutter rotary drill bit.

39. The PCD element of claim 37, wherein the cutting element is mounted upon a body of a rolling cutter drill bit.

40. The PCD element of claim 37 wherein the substrate is tungsten carbide with an iron group binder material.

41. A PCD element comprising a body integrally formed with a metallic substrate, the body comprising a plurality of bonded diamond crystals having surfaces and a catalyzing material, the body having at least an 85% by volume diamond density, wherein at least 30% of the crystals in the body contact the catalyzing material and the surfaces of a majority of the remaining crystals that are within at least a 0.1 mm depth from a working surface are substantially free of the catalyzing material.

42. The PCD element of claim 41, wherein said majority of the crystals in the body are within between about 0.2 mm and 0.3 mm depth from the working surface.

43. The PCD element of claim 41 wherein the substrate is tungsten carbide with an iron group binder material.

44. A method of manufacture of a PCD element comprising a body integrally formed with a metallic substrate, the body comprising bonded diamond crystals and a catalyzing material, by treating the body to render a volume thereof substantially free of the catalyzing material while permitting the catalyzing material to remain in at least some of the remaining volume of the body and while permitting the substrate to remain substantially unaffected when treating the body.

45. The method of claim 44, wherein the volume is rendered substantially free of catalyzing material by leaching the catalyzing material from the second volume.

46. The method of claim 44, wherein the volume is rendered substantially free of catalyzing material by converting the catalyzing material in the second volume to a form in which it does not have a catalyzing effect.

47. The method of claim 44, wherein the volume is rendered substantially free of catalyzing material by reacting the catalyzing material to form a substance which does not have a catalyzing effect.

48. The method of claim 44, wherein the volume is rendered substantially free of catalyzing material by electrical discharge.

49. The method of claim 44, wherein the volume is rendered substantially free of catalyzing material using a galvanic process.

50. The method of claim 44, wherein the volume is rendered substantially free of catalyzing material using an evaporation process.