IP Library Granted Patent US 12,296,435
Granted Patent B2
US 12,296,435 · App. 18/371,298 · Granted May 13, 2025

Leached superabrasive elements and systems, methods and assemblies for processing superabrasive materials

Inventors: Daniel Marin Scott (Laie, HI); Daren Nathaniel Heaton (Spanish Fork, UT); Jeremy Brett Lynn (Nephi, UT); Mark Pehrson Chapman (Provo, UT); Oakley D. Bond (Nephi, UT)
Assignee: US Synthetic Corporation
B24D3/005B24D3/10B24D18/00B24D18/0009B24D99/005C25F3/02C25F7/00F16C33/043F16C33/26B22F2999/00F16C17/02F16C17/04
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Quick Facts
Patent No.
US 12,296,435
App. No.
18/371,298
Granted
May 13, 2025
Kind
B2
Abstract

A method of processing a superabrasive element includes providing a superabrasive element including a polycrystalline diamond table that includes a metallic material disposed in interstitial spaces defined within the polycrystalline diamond table. The method also includes leaching the metallic material from at least a volume of the polycrystalline diamond table to produce a leached volume in the polycrystalline diamond table.

Claims (58)

1. A superabrasive element comprising:

a polycrystalline diamond table comprising:

a metallic material disposed in interstitial spaces defined within the polycrystalline diamond table;

an unleached volume including the metallic material disposed in the interstitial spaces defined within the polycrystalline diamond table; and

a leached volume where at least some of the metallic material disposed in the interstitial spaces defined within the polycrystalline diamond table has been removed with a leaching process,

wherein at least a portion of a cobalt material has been removed from the metallic material in the interstitial spaces in the leached volume of the polycrystalline diamond table while a tungsten material remains in the interstitial spaces in the leached volume of the polycrystalline diamond table, and

wherein the metallic material in the interstitial spaces in the leached volume of the polycrystalline diamond table includes a ratio of the cobalt material relative to the tungsten material that is greater than a ratio of a cobalt material relative to a tungsten material in the unleached volume of the polycrystalline diamond table.

2. The superabrasive element of claim 1 , wherein the cobalt material in the interstitial spaces in the leached volume of the polycrystalline diamond table has been substantially removed from the metallic material.

3. The superabrasive element of claim 1 , wherein an amount of the tungsten material in the interstitial spaces in the leached volume of the polycrystalline diamond table is similar to another amount of tungsten material in the interstitial spaces in the unleached volume of the polycrystalline diamond table.

4. The superabrasive element of claim 1 , wherein the metallic material from a portion of the polycrystalline diamond table has been leached to a first depth relative to a superabrasive face of the superabrasive element, and wherein the metallic material from an external side region of the polycrystalline diamond table has been leached to a second depth relative to the superabrasive face of the superabrasive element, the second depth being greater than the first depth.

5. The superabrasive element of claim 1 , wherein the leaching process comprises:

exposing at least a portion of the polycrystalline diamond table to a processing solution; and

applying a charge to the processing solution to generate a voltage between the polycrystalline diamond table and an electrode via the processing solution.

6. The superabrasive element of claim 5 , wherein the processing solution includes an organic acid and a divalent metal salt.

7. The superabrasive element of claim 6 , wherein the divalent metal salt comprises a Group II metal salt selected from the group consisting of fluoride, chloride, bromide, and iodide salts of beryllium, magnesium, calcium, strontium and barium, and combinations thereof.

8. The superabrasive element of claim 1 , wherein the interstitial spaces in the leached volume of the polycrystalline diamond table substantially lacks the cobalt material while the tungsten material remains in the interstitial spaces in the leached volume of the polycrystalline diamond table.

9. The superabrasive element of claim 1 , further comprising a substrate attached to the polycrystalline diamond table.

10. The superabrasive element of claim 9 , further comprising a protective layer surrounding at least the substrate.

11. A superabrasive element comprising:

a polycrystalline diamond table comprising:

a metallic material disposed in interstitial spaces defined within the polycrystalline diamond table;

an unleached volume including the metallic material disposed in the interstitial spaces defined within the polycrystalline diamond table; and

a leached volume where at least some of the metallic material disposed in the interstitial spaces defined within the polycrystalline diamond table has been removed with a leaching process,

wherein at least a portion of a cobalt material has been removed from the metallic material in the interstitial spaces in the leached volume of the polycrystalline diamond table while a tungsten material remains in the interstitial spaces in the leached volume of the polycrystalline diamond table, and

wherein:

an amount of the tungsten material in the interstitial spaces in the leached volume of the polycrystalline diamond table is similar to another amount of tungsten material in the interstitial spaces in the unleached volume of the polycrystalline diamond table; or

the metallic material from a portion of the polycrystalline diamond table has been leached to a first depth relative to a superabrasive face of the superabrasive element, and wherein the metallic material from an external side region of the polycrystalline diamond table has been leached to a second depth relative to the superabrasive face of the superabrasive element, the second depth being greater than the first depth.

12. The superabrasive element of claim 11 , wherein at least a portion of the polycrystalline diamond table has been exposed to a charged processing solution including an organic acid and a divalent metal salt in the leaching process.

13. The superabrasive element of claim 11 , further comprising a substrate having a protective layer attached to the polycrystalline diamond table.

14. A superabrasive element comprising:

a polycrystalline diamond table comprising:

a metallic material disposed in interstitial spaces defined within the polycrystalline diamond table;

an unleached volume including the metallic material disposed in the interstitial spaces defined within the polycrystalline diamond table; and

a leached volume where at least some of the metallic material disposed in the interstitial spaces defined within the polycrystalline diamond table has been removed with a leaching process,

wherein at least a portion of a cobalt material has been removed from the metallic material in the interstitial spaces in the leached volume of the polycrystalline diamond table while a tungsten material remains in the interstitial spaces in the leached volume of the polycrystalline diamond table;

wherein the leaching process comprises:

exposing at least a portion of the polycrystalline diamond table to a processing solution; and

applying a charge to the processing solution to generate a voltage between the polycrystalline diamond table and an electrode via the processing solution; and

wherein the processing solution includes an organic acid and a divalent metal salt.

15. The superabrasive element of claim 14 , wherein the divalent metal salt comprises a Group II metal salt selected from the group consisting of fluoride, chloride, bromide, and iodide salts of beryllium, magnesium, calcium, strontium and barium, and combinations thereof.

16. The superabrasive element of claim 14 , wherein an amount of the tungsten material in the interstitial spaces in the leached volume of the polycrystalline diamond table is similar to another amount of tungsten material in the interstitial spaces in the unleached volume of the polycrystalline diamond table.

17. The superabrasive element of claim 14 , wherein the metallic material from a portion of the polycrystalline diamond table has been leached to a first depth relative to a superabrasive face of the superabrasive element, and wherein the metallic material from an external side region of the polycrystalline diamond table has been leached to a second depth relative to the superabrasive face of the superabrasive element, the second depth being greater than the first depth.

18. A superabrasive element comprising:

a polycrystalline diamond table comprising:

a metallic material disposed in interstitial spaces defined within the polycrystalline diamond table;

an unleached volume including the metallic material disposed in the interstitial spaces defined within the polycrystalline diamond table; and

a leached volume where at least some of the metallic material disposed in the interstitial spaces defined within the polycrystalline diamond table has been removed with a leaching process,

wherein at least a portion of a cobalt material has been removed from the metallic material in the interstitial spaces in the leached volume of the polycrystalline diamond table while a tungsten material remains in the interstitial spaces in the leached volume of the polycrystalline diamond table; and

wherein the interstitial spaces in the leached volume of the polycrystalline diamond table substantially lacks the cobalt material while the tungsten material remains in the interstitial spaces in the leached volume of the polycrystalline diamond table.

19. A superabrasive element comprising:

a polycrystalline diamond table comprising:

a metallic material disposed in interstitial spaces defined within the polycrystalline diamond table;

an unleached volume including the metallic material disposed in the interstitial spaces defined within the polycrystalline diamond table; and

a leached volume where at least some of the metallic material disposed in the interstitial spaces defined within the polycrystalline diamond table has been removed with a leaching process;

a substrate attached to the polycrystalline diamond table; and

a protective layer surrounding at least the substrate,

wherein at least a portion of a cobalt material has been removed from the metallic material in the interstitial spaces in the leached volume of the polycrystalline diamond table while a tungsten material remains in the interstitial spaces in the leached volume of the polycrystalline diamond table.

20. The superabrasive element of claim 19 , wherein the metallic material in the interstitial spaces in the leached volume of the polycrystalline diamond table includes relatively less of the cobalt material than the metallic material in the interstitial spaces in the unleached volume of the polycrystalline diamond table.

Assignments (2)
SECURITY INTEREST Recorded Jul 18, 2025
From: US SYNTHETIC CORPORATION
To: KEYBANK NATIONAL ASSOCIATION
Reel/Frame 074973/0089 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Sep 22, 2023
From: SCOTT, DANIEL MARIN; HEATON, DAREN NATHANIEL; LYNN, JEREMY BRETT; CHAPMAN, MARK PEHRSON; BOND, OAKLEY D.
To: US SYNTHETIC CORPORATION
Reel/Frame 064994/0105 →
Continuity (5)
Continuation 16993055 · Aug 13, 2020
Continuation In Part 16020751 · Jun 27, 2018
Continuation 14864152 · Sep 24, 2015
Provisional Application 62062553 · Oct 10, 2014
Related Publication 20240009808A1 · Jan 11, 2024
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