Superabrasive articles and methods for removing interstitial materials from superabrasive materials

1. A method of processing a polycrystalline diamond material, the method comprising:

leaching a metal-solvent catalyst from a polycrystalline diamond material by exposing at least a portion of the polycrystalline diamond material to a leaching composition, the leaching composition comprising:

water;

a complexing agent at a molar concentration of between approximately 0.01 M and approximately 0.5 M;

hydrofluoric acid.

2. The method of claim 1 , wherein the complexing agent comprises a chelating agent.

3. The method of claim 1 , wherein the complexing agent comprises a phosphate.

4. The method of claim 1 , wherein the complexing agent comprises a weak acid having an acid dissociation constant (pKa) of between approximately −2 and 12.

5. The method of claim 1 , wherein the complexing agent comprises at least one of:

phosphoric acid;

citric acid;

tartaric acid;

oxalic acid;

ammonium chloride.

6. The method of claim 1 , wherein the leaching composition comprises the complexing agent at a molar concentration of approximately 0.125 M.

7. The method of claim 1 , wherein the metal-solvent catalyst comprises at least one of:

cobalt;

nickel;

iron.

8. The method of claim 1 , wherein the leaching composition further comprises at least one of:

nitric acid;

hydrochloric acid;

sulfuric acid;

boric acid.

9. The method of claim 1 , wherein the leaching composition comprises the hydrofluoric acid at a molar concentration of between approximately 0.1 M and approximately 3 M.

10. The method of claim 1 , wherein the leaching composition comprises the hydrofluoric acid at a molar concentration of approximately 1.5 M.

11. The method of claim 1 , wherein the leaching composition further comprises a peroxide.

12. The method of claim 1 , wherein the complexing agent forms metal complexes with tungsten.

13. The method of claim 12 , wherein the metal complexes are soluble in the leaching composition.

14. The method of claim 12 , wherein each of the metal complexes comprises:

a tungsten atom:

between 2 and 4 ligands.

15. The method of claim 1 , wherein:

the polycrystalline diamond material comprises bonded diamond grains;

at least a portion of tungsten in the polycrystalline diamond material and at least a portion of the metal-solvent catalyst are disposed between the bonded diamond grains.

16. The method of claim 1 , further comprising exposing at least a portion of the polycrystalline diamond material and the leaching composition to a temperature of between approximately 25° C. and approximately 280° C.

17. The method of claim 1 , further comprising exposing at least a portion of the polycrystalline diamond material and the leaching composition to a pressure of between approximately 20 bar and approximately 100 bar.

18. The method of claim 1 , further comprising exposing at least a portion of the polycrystalline diamond material and the leaching composition to at least one of:

an electric current;

microwave radiation;

ultrasonic energy.

19. A method of processing a superabrasive element, the method comprising:

providing a superabrasive element comprising:

a substrate;

a polycrystalline diamond table bonded to the substrate, the polycrystalline diamond table comprising tungsten and a metal-solvent catalyst;

leaching at least a portion of the metal-solvent catalyst from the polycrystalline diamond table by exposing at least a portion of the polycrystalline diamond table to a leaching composition, the leaching composition comprising:

water;

a complexing agent at a molar concentration of between approximately 0.01 M and approximately 0.5 M;

hydrofluoric acid.

20. A method of processing a polycrystalline diamond material, the method comprising:

providing a polycrystalline diamond material, the polycrystalline diamond material comprising:

bonded diamond grains;

tungsten;

a metal-solvent catalyst;

exposing the polycrystalline diamond material to a leaching composition, the leaching composition comprising:

water;

a complexing agent at a molar concentration of between approximately 0.01 M and approximately 0.5 M;

hydrofluoric acid;

forming metal complexes within the polycrystalline diamond material, the metal complexes comprising:

at least a portion of the tungsten;

at least a portion of the complexing agent;

extracting the metal-solvent catalyst from the polycrystalline diamond material.

21. The method of claim 1 , wherein the leaching composition comprises the hydrofluoric acid at a molar concentration of between approximately 1 M and approximately 2 M.