Methods of fabricating a polycrystalline diamond compact

1. A method of fabricating a polycrystalline diamond compact, the method comprising:

forming a polycrystalline diamond body in a first high-pressure/high-temperature process performed at a first cell pressure of at least 8 GPa;

leaching the polycrystalline diamond body to at least partially remove a catalyst therefrom, thereby forming an at least partially leached polycrystalline diamond body; and

subjecting the at least partially leached polycrystalline diamond body and a substrate to a second high-pressure/high-temperature process, at a second cell pressure of 7.5 GPa to 8.0 GPa, to infiltrate the at least partially leached polycrystalline diamond body with an infiltrant.

2. The method of claim 1 wherein the first cell pressure of the first high-pressure/high-temperature process is 8 GPa to about 12 GPa cell pressure.

3. The method of claim 1 wherein the plurality of diamond particles exhibits an average diamond particle size of about 30 μm or less.

4. The method of claim 3 wherein, before leaching, the polycrystalline diamond body exhibits a coercivity of about 115 Oersteds (“Oe”) or more, and a specific magnetic saturation of about 15 Gauss·cm 3 /grams (“G·cm 3 /g”) or less.

5. The method of claim 4 wherein, before leaching, the coercivity is about 115 Oe to about 250 Oe, and the specific magnetic saturation is about 5 G·cm 3 /g to about 15 G·cm 3 /g.

6. The method of claim 1 , further comprising leaching the infiltrated polycrystalline diamond body to at least partially remove the infiltrant therefrom.

7. The method of claim 6 wherein the infiltrant includes a metallic infiltrant.

8. The method of claim 7 wherein the metallic infiltrant includes cobalt.

9. The method of claim 1 wherein the substrate includes the infiltrant.

10. The method of claim 1 wherein the catalyst includes a metal-solvent catalyst.

11. The method of claim 1 wherein forming a polycrystalline diamond body in a first high-pressure/high-temperature process performed at a first cell pressure includes forming the polycrystalline diamond body on a cemented carbide substrate.

12. The method of claim 1 wherein, before leaching, the polycrystalline diamond body includes greater than 0 weight % to about 7.5 weight % of the catalyst.

13. A method of fabricating a polycrystalline diamond compact, the method comprising:

sintering a plurality of diamond particles in the presence of a metal-solvent catalyst to form a polycrystalline diamond body, wherein the sintering is performed in a first high-pressure/high-temperature process at a first cell pressure and a first temperature effective to form the polycrystalline diamond body with a coercivity of about 115 Oersteds (“Oe”) or more and a specific magnetic saturation of about 15 Gauss·cm 3 /grams (“G·cm 3 /g”) or, wherein the first cell pressure is 9.0 GPa to 15 GPa;

leaching the polycrystalline diamond body to at least partially remove the metal-solvent catalyst therefrom, thereby forming an at least partially leached polycrystalline diamond body; and

subjecting an assembly of the at least partially leached polycrystalline diamond body and a cemented carbide substrate to a second high-pressure/high-temperature process at a second cell pressure and second temperature effective to infiltrate the at least partially leached polycrystalline diamond body with an infiltrant, wherein the second cell pressure of the second high-pressure/high-temperature process is 7.5 GPa to 9.0 GPa.

14. The method of claim 13 wherein the first cell pressure at which the plurality of diamond particles is sintered is 9 GPa to about 12 GPa cell pressure.

15. The method of claim 13 wherein the plurality of diamond particles exhibits an average diamond particle size of about 30 μm or less.

16. The method of claim 13 wherein the coercivity is about 115 Oe to about 250 Oe, and the specific magnetic saturation is about 5 G·cm 3 /g to about 15 G·cm 3 /g.

17. The method of claim 13 wherein the cemented carbide substrate includes chromium carbide.

18. A method of fabricating a polycrystalline diamond compact, the method comprising:

sintering a plurality of diamond particles in the presence of a metal-solvent catalyst to form a polycrystalline diamond body at a first cell pressure of about 8 GPa to about 12 GPa, wherein the plurality of diamond particles exhibits an average particle size of about 20 μm or less, wherein the polycrystalline diamond body exhibits a coercivity of about 115 Oersteds or more, wherein the polycrystalline diamond body exhibits a specific magnetic saturation of about 15 Gauss·cm 3 /grams or less;

at least partially removing the metal-solvent catalyst from the polycrystalline diamond body to form an at least partially leached polycrystalline diamond body; and

subjecting an assembly of the at least partially leached polycrystalline diamond body and a cemented carbide substrate to a high-pressure/high-temperature process to infiltrate the at least partially leached polycrystalline diamond body with an infiltrant from the cemented carbide substrate.

19. The method of claim 18 , further comprising leaching the infiltrated polycrystalline diamond body to at least partially remove the infiltrant therefrom.

20. The method of claim 19 wherein the infiltrant includes a metallic infiltrant.

21. The method of claim 20 wherein the metallic infiltrant includes cobalt.

22. The method of claim 13 wherein a difference between the first cell pressure and the second cell pressure is at least 0.5 GPa.

23. The method of claim 13 , further comprising leaching the infiltrated polycrystalline diamond body to at least partially remove the infiltrant therefrom.

24. The method of claim 23 wherein the infiltrant includes a metallic infiltrant.

25. The method of claim 24 wherein the metallic infiltrant includes cobalt.

26. The method of claim 22 wherein the difference is at least 1.5 GPa.

27. The method of claim 22 wherein the difference is at least 2.5 GPa.