In-situ boron doped PDC element

• US 8,997,900 B2
• Filed: 12/15/2010
• Issued: 04/07/2015
• Est. Priority Date: 12/15/2010
• Status: Active Grant

• Current Assignee: National Oilwell DHT, LP (NOV, Inc.)
• Original Assignee: National Oilwell DHT, LP (NOV, Inc.)
• Inventors: Sue, Jiinjen Albert, Sreshta, Harold
• Primary Examiner(s): Gay, Jennifer H
• Assistant Examiner(s): BUTCHER, CAROLINE N
• Application Number:
  US12/968,590
• Publication Number:
  US 20120152622A1
• Time in Patent Office: 1,574 Days
• Field of Search: None
• US Class Current: 175/434
• CPC Class Codes: B24D 18/0009 using moulds or presses
• CPC Class Codes: B24D 3/06 metallic or mixture of metals with ceramic materials, e.g. hard metals, "cermets", cements
• CPC Class Codes: E21B 10/56 Button-type inserts E21B10/52 takes precedence
• CPC Class Codes: E21B 10/567 with preformed cutting elements mounted on a distinct support, e.g. polycrystalline inserts
• CPC Class Codes: E21B 10/573 characterised by support details, e.g. the substrate construction or the interface between the substrate and the cutting element

Abstract

A polycrystalline diamond compact formed in an in-situ boron-doped process. The in-situ boron-doped process includes consolidating a mixture of diamond crystals and boron-containing alloy via liquid diffusion of boron into diamond crystals at a pressure greater than 5 Gpa and at a temperature greater than the melting temperature of the boron-containing alloy, typically less than about 1450° C.

Claims

1. A polycrystalline diamond compact, comprising:

a layer of polycrystalline diamond integrally formed in a high-temperature, high-pressure in-situ boron-doped process, the layer comprising a generally uniform mixture of diamond crystals and boron-containing alloy formed of Ni—

, Co—

or Fe—

, and boron powder, said boron-containing alloy having a melting temperature between about 960°

C. and about 1200°

C., said mixture being consolidated via liquid diffusion of boron into the diamond crystals at a pressure between about 5 Gpa and about 7 Gpa and at a temperature greater than 950°

C. and less than 1450°

C.

2. The polycrystalline diamond compact of claim 1, wherein the diamond crystals comprise a synthetic diamond and wherein the boron-containing alloy comprises Ni, Co and Fe-base alloys having a melting temperature less than about 1200°

C.

3. The polycrystalline diamond compact of claim 2, wherein the boron-containing alloy comprises Ni, Co and Fe-base alloys having a minimum melting temperature of 1000°

C.

4. The polycrystalline diamond compact of claim 3, wherein the boron-containing alloy and the Ni, Co and Fe-base alloys have a melting temperature below about 1100°

C. and wherein the boron-containing alloy comprises the Ni, Co and Fe-base alloys.

5. The polycrystalline diamond compact of claim 4, wherein the melting temperature is greater than 1000°

C. and less than 1200°

C.

6. The polycrystalline diamond compact of claim 2, wherein the diamond crystals have a particle size between 8 μ

m and 10 μ

m.

7. The polycrystalline diamond compact of claim 1, wherein the diamond crystal comprises synthetic diamond and boron-doped diamond crystals manufactured by chemical vapor deposition and high-temperature, high-pressure processes, and natural diamonds comprising a source material.

8. The polycrystalline diamond compact of claim 7, wherein the boron-containing alloy comprises Ni, Co and Fe-base alloys having a melting temperature below about 1200°

C.

9. The polycrystalline diamond compact of claim 8, wherein the melting temperature of the Ni, Co and Fe-base alloys is below about 1200°

C.

10. The polycrystalline diamond compact of claim 1, wherein a source of the polycrystalline diamond comprises synthetic diamond and wherein the boron-containing alloy comprises Ni, Co and Fe-base alloys having a melting temperature of less than about 1200°

C.

11. An earth boring drill bit, comprising:

a polycrystalline diamond cutting element with a layer of polycrystalline diamond integrally formed in a high-temperature, high-pressure in-situ boron-doped process, the layer comprising an in-situ boron-doped polycrystalline diamond compact comprising a generally uniform mixture of diamond crystals and boron-containing alloy formed of Ni—

, Co—

or Fe—

, and boron powder, said boron-containing alloy having a melting temperature between about 960°

C. and about 1200°

C., said mixture being consolidated via liquid diffusion of boron into the diamond crystals at a pressure greater than 5 Gpa and less than 7 Gpa and at a temperature greater than 950°

C. and less than 1450°

C.

12. A method for making an in-situ boron-doped polycrystalline diamond compact, comprising:

forming a layer of polycrystalline diamond integrally in a high-temperature, high-pressure in-situ boron-doped process comprising in-situ boron-doped polycrystalline diamond compact by consolidating a generally uniform mixture of diamond crystals and boron-containing alloy formed of Ni—

, Co—

or Fe—

, and boron powder, said boron-containing alloy having a melting temperature between about 960°

C. and about 1200°

C., said mixture formed via liquid diffusion of boron into diamond crystals at a pressure greater than 5 Gpa and less than 7 Gpa and at a temperature greater than 950°

C. and less than 1195°

C.

13. The method of claim 12 wherein synthetic diamond and boron-doped diamond crystals manufactured by chemical vapor deposition and high-temperature, high-pressure processes, and natural diamonds are used as a source material.

14. The method of claim 13 wherein the boron-containing alloy comprises Ni-, Co-, and Fe-base alloys, or mixtures thereof, having melting temperatures below 1200°

C. and wherein the method further comprises converting diamond from graphite having a pressure of greater than 5.5 Gpa.

15. The method of claim 14, wherein the melting temperature of the boron-containing alloy is between about 960°

C. to 1200°

C.

16. The method of claim 15, wherein the boron-containing alloy suppresses sp2 carbon formation, thereby improving crystallinity of the in-situ boron-doped polycrystalline diamond compact.

17. The method of claim 15, wherein the boron-containing alloy is enabled by the in-situ boron doped high-temperature, high-pressure to effectively consolidate a polycrystalline diamond mass with diamond crystals sizes less than 10 μ

m.

18. A polycrystalline diamond cutting element, comprising:

a preform cutting element in a fixed cutter rotary drill bit, the preform cutting element having a body in a form of a circular tablet with a front facing table of polycrystalline diamond that is integrally formed with a substrate of less hard material and bonded on a generally cylindrical carrier, the preformed cutting element formed in a high-temperature, high-pressure in-situ boron-doped process, the tablet comprising an in-situ boron-doped formed polycrystalline diamond compact comprising a generally uniform mixture of diamond crystals and boron-containing alloy formed of Ni—

, Co—

or Fe—

, and boron powder, said boron-containing alloy having a melting temperature between about 960°

C. and about 1200°

C., said mixture consolidated via liquid diffusion of boron into diamond crystals at a pressure between about 5 Gpa and about 7 Gpa and at a temperature greater than 950°

C. and less than 1450°

C.

19. The polycrystalline diamond cutting element of claim 18, wherein the preform cutting element has relatively lower residual compressive stress compared to un-doped preform cutting element that was manufactured under the same high-temperature, high-pressure process parameters.

20. The polycrystalline diamond cutting element of claim 18, wherein the cutting element is located on the body of the fixed cutter rotary drill bit adapted for casing milling and formation drilling such that it is a primarily cutting element for drilling through steel casing.

21. The polycrystalline diamond cutting element of claim 18, wherein the in-situ boron doped polycrystalline diamond cutting element is fixed upon a body of the fixed cutter rotary drill bit adapted for geothermal drilling.