Method of fabricating polycrystalline diamond and a polycrystalline diamond compact
View Patent ↗Embodiments of the invention relate to polycrystalline diamond (“PCD”) exhibiting enhanced diamond-to-diamond bonding. In an embodiment, PCD includes a plurality of diamond grains defining a plurality of interstitial regions. A metal-solvent catalyst occupies at least a portion of the plurality of interstitial regions. The plurality of diamond grains and the metal-solvent catalyst collectively exhibit a coercivity of about 115 Oersteads (“Oe”) or more and a specific magnetic saturation of about 15 Gauss·cm 3 /grams (“G·cm 3 /g”) or less. Other embodiments are directed to polycrystalline diamond compacts (“PDCs”) employing such PCD, methods of forming PCD and PDCs, and various applications for such PCD and PDCs in rotary drill bits, bearing apparatuses, and wire-drawing dies.
1. A method of forming a polycrystalline diamond compact, comprising:
enclosing a plurality of diamond particles that exhibit an average particle size of about 30 μm or less, and a cemented carbide substrate including a metal-solvent catalyst therein in a pressure transmitting medium to form a cell assembly; and
subjecting the cell assembly to a temperature of at least about 1400° Celsius and a pressure in the pressure transmitting medium of at least about 7.5 GPa to infiltrate the plurality of diamond particles with a portion of the metal-solvent catalyst and catalyze formation of a polycrystalline diamond table that bonds to the cemented carbide substrate, wherein the polycrystalline diamond table includes about 1 weight % to about 6 weight % of the metal-solvent catalyst therein.
2. The method of claim 1 wherein subjecting the cell assembly to a temperature of at least about 1400° Celsius and a pressure in the pressure transmitting medium of at least about 7.5 GPa comprises subjecting the cell assembly to a pressure in the pressure transmitting medium of at least about 8.0 GPa.
3. The method of claim 1 wherein subjecting the cell assembly to a temperature of at least about 1400° Celsius and a pressure in the pressure transmitting medium of at least about 7.5 GPa comprises subjecting the cell assembly to a pressure in the pressure transmitting medium of at least about 9.0 GPa.
4. The method of claim 1 wherein subjecting the cell assembly to a temperature of at least about 1400° Celsius and a pressure in the pressure transmitting medium of at least about 7.5 GPa comprises subjecting the cell assembly to a pressure in the pressure transmitting medium of at least about 10.0 GPa.
5. The method of claim 1 wherein the polycrystalline diamond table exhibits a coercivity of about 115 Oe or more.
6. The method of claim 1 wherein the polycrystalline diamond table exhibits a coercivity of about 115 Oe to about 250 Oe and a specific magnetic saturation of about 5 G·cm 3 /g to about 15 G·cm 3 /g.
7. The method of claim 1 wherein the polycrystalline diamond table exhibits a coercivity of about 130 Oe to about 160 Oe, a specific magnetic saturation of about 10 G·cm 3 /g to about 15 G·cm 3 /g, and the metal-solvent catalyst is present in an amount of about 3 weight % to about 6 weight %.
8. The method of claim 1 wherein the polycrystalline diamond table comprises a plurality of diamond grains defining a plurality of interstitial regions, the metal-solvent catalyst occupying at least a portion of the plurality of interstitial regions.
9. The method of claim 1 wherein the amount of the metal-solvent catalyst present in the polycrystalline diamond table is about 3 weight % to about 6 weight %.
10. The method of claim 1 wherein the amount of the metal-solvent catalyst present in the polycrystalline diamond table is about 1 weight % to about 3 weight %.
11. The method of claim 1 wherein the amount of the metal-solvent catalyst present in the polycrystalline diamond is about 1 weight %.
12. The method of claim 1 wherein the cemented carbide substrate comprises chromium carbide.
13. The method of claim 1 wherein the average particle size of the plurality of diamond particles is about 20 μm or less.
14. The method of claim 1 wherein the average particle size of the plurality of diamond particles is about 10 μm or less.
15. The method of claim 1 wherein subjecting the cell assembly to a temperature of at least about 1400° Celsius and a pressure in the pressure transmitting medium of at least about 7.5 GPa comprises selecting the pressure so that the polycrystalline diamond exhibits a residual principal stress on a working surface thereof of about −345 MPa to about 0 MPa.
16. The method of claim 1 wherein the polycrystalline diamond table exhibits a thermal stability of at least about 1300 m as determined by a distance cut, prior to failure, in a vertical lathe test.
17. The method of claim 1 wherein the pressure transmitting medium comprises a gasket material, and wherein the cell assembly is a cubic cell assembly.
18. A method of fabricating a polycrystalline diamond compact, comprising:
enclosing a plurality of diamond particles that exhibit an average particle size of about 20 μm or less, and a substrate including a metal-solvent catalyst therein in a pressure transmitting medium to form a cell assembly; and
subjecting the cell assembly to a temperature of at least about 1000° Celsius and a pressure in the pressure transmitting medium of at least about 7.5 GPa to infiltrate the plurality of diamond particles with a portion of the metal-solvent catalyst and catalyze formation of a polycrystalline diamond table bonded to the substrate, wherein the polycrystalline diamond table includes about 1 weight % to about 7.5 weight % of the metal-solvent catalyst therein.
19. The method of claim 18 wherein the polycrystalline diamond table exhibits a coercivity of about 130 Oe to about 160 Oe, a specific magnetic saturation of about 10 G·cm 3 /g to about 15 G·cm 3 /g, and the metal-solvent catalyst is present in an amount of about 3 weight % to about 7.5 weight %.
20. The method of claim 18 wherein the pressure in the pressure transmitting medium is about 7.5 GPa to about 15 GPa.
21. The method of claim 18 wherein the polycrystalline diamond table exhibits a coercivity of about 115 Oe or more.
22. The method of claim 18 wherein the polycrystalline diamond table exhibits a coercivity of about 115 Oe to about 250 Oe and a specific magnetic saturation of about 5 G·cm 3 /g to about 15 G·cm 3 /g.
23. The method of claim 18 wherein the polycrystalline diamond table exhibits a coercivity of about 130 Oe to about 160 Oe, a specific magnetic saturation of about 10 G·cm 3 /g to about 15 G·cm 3 /g, and the metal-solvent catalyst is present in an amount of about 3 weight % to about 6 weight %.
24. The method of claim 18 wherein the amount of the metal-solvent catalyst present in the polycrystalline diamond table is about 3 weight % to about 6 weight %.
25. The method of claim 18 wherein the amount of the metal-solvent catalyst present in the polycrystalline diamond table is about 1 weight % to about 3 weight %.
26. The method of claim 18 wherein the polycrystalline diamond table exhibits a thermal stability of at least about 1300 m as determined by a distance cut, prior to failure, in a vertical lathe test.
27. The method of claim 1 wherein the pressure in the pressure transmitting medium is about 7.5 GPa to about 15 GPa.