Polycrystalline diamond compacts having leach depths selected to control physical properties and methods of forming such compacts

Patent metadata

Field	Value
Publication number	US-2017029338-A1
Application number	US-201514815608-A
Country	US
Kind code	A1
Filing date	Jul 31, 2015
Priority date	Jul 31, 2015
Publication date	Feb 2, 2017
Grant date	—

Abstract

A method of forming a polycrystalline diamond compact includes forming a polycrystalline diamond material at a temperature and a pressure sufficient to form diamond-to-diamond bonds in the presence of a catalyst; substantially removing the catalyst from a volume of the polycrystalline diamond material from a first surface to a first leach depth; and substantially removing the catalyst from a volume of the polycrystalline diamond material from a second surface to a second, different leach depth. A polycrystalline diamond compact includes a polycrystalline diamond material having a first volume, a second volume, and a boundary between the first volume and the second volume. The first volume includes a catalyst disposed in interstitial spaces between diamond grains. The second volume is substantially free of the catalyst. The boundary's location is selected to control thermal stability and/or impact resistance.

First claim

What is claimed is:

1 . A method of forming a polycrystalline diamond compact, the method comprising:
forming a polycrystalline diamond material from diamond particles at a temperature and a pressure sufficient to form diamond-to-diamond bonds in the presence of a catalyst; selecting a first leach depth from a first surface of the polycrystalline diamond material to control at least one of thermal stability and impact resistance; substantially removing the catalyst from a volume of the polycrystalline diamond material from the first surface to the first leach depth; selecting a second, different leach depth from a second surface of the polycrystalline diamond material to control at least one of thermal stability and impact resistance; and substantially removing the catalyst from a volume of the polycrystalline diamond material from the second surface to the second leach depth.

2 . The method of claim 1 , wherein forming a polycrystalline diamond material comprises forming the polycrystalline diamond material on a supporting substrate.

3 . The method of claim 1 , wherein forming a polycrystalline diamond material comprises forming the polycrystalline diamond material as a freestanding structure.

4 . The method of claim 1 , wherein the first surface comprises a cutting face of the polycrystalline diamond material, and wherein the second surface comprises a side surface of the polycrystalline diamond material.

5 . The method of claim 1 , wherein substantially removing the catalyst from a volume of the polycrystalline diamond material from the second surface to the second leach depth comprises:
removing the catalyst through the second surface without substantially removing the catalyst through the first surface; and removing the catalyst through the second surface and the first surface simultaneously.

6 . The method of claim 5 , further comprising masking the first surface before removing the catalyst through the second surface without substantially removing the catalyst through the first surface.

7 . The method of claim 1 , wherein substantially removing the catalyst from the volume of the polycrystalline diamond material comprises leaching the catalyst.

8 . The method of claim 1 , further comprising providing a backfill material into the volume of the polycrystalline diamond material.

9 . The method of claim 8 , wherein the catalyst and the backfill material each comprise substantially the same material.

10 . The method of claim 8 , wherein the backfill material exhibits a coefficient of thermal expansion lower than a coefficient of thermal expansion of the catalyst.

11 . A polycrystalline diamond compact, comprising:
a polycrystalline diamond material comprising a first volume, a second volume, and a boundary between the first volume and the second volume; the first volume comprising a plurality of diamond grains bonded to one another by diamond-to-diamond bonds and a catalyst disposed in interstitial spaces between the diamond grains; the second volume comprising a plurality of diamond grains bonded to one another by diamond-to-diamond bonds, wherein the second volume is substantially free of the catalyst; and the boundary comprising a first leach depth from a first surface of the polycrystalline diamond material and a second, different leach depth from a second surface of the polycrystalline diamond material, the first leach depth and the second leach depth each selected to control at least one of thermal stability and impact resistance.

12 . The polycrystalline diamond compact of claim 11 , wherein the polycrystalline diamond material is secured to a supporting substrate.

13 . The polycrystalline diamond compact of claim 11 , wherein the polycrystalline diamond material comprises a freestanding structure.

14 . The polycrystalline diamond compact of claim 11 , wherein the first surface comprises a cutting face of the polycrystalline diamond material, and wherein the second surface comprises a side surface of the polycrystalline diamond material.

15 . The polycrystalline diamond compact of claim 14 , wherein the second leach depth is greater than the first leach depth.

16 . The polycrystalline diamond compact of claim 11 , wherein the diamond grains comprise nanodiamond grains.

17 . The polycrystalline diamond compact of claim 11 , wherein the boundary comprises a third leach depth from a third surface of the polycrystalline diamond material.

18 . The polycrystalline diamond compact of claim 17 , wherein the third leach depth is equal to the first leach depth or the second leach depth.

19 . An earth-boring tool comprising:
a bit body; and the polycrystalline diamond compact of claim 14 .

20 . A method of forming a polycrystalline diamond compact, the method comprising:
forming a polycrystalline diamond material from diamond particles at a temperature and a pressure sufficient to form diamond-to-diamond bonds in the presence of a catalyst; selecting at least one leach depth from at least one surface of the polycrystalline diamond material to optimize thermal stability and impact resistance; and substantially removing the catalyst from a volume of the polycrystalline diamond material from the at least one surface to the at least one leach depth.

Assignees

• Baker Hughes Inc

Inventors

• Scott Danny E
• Cao Wanjun

Classifications

• E21B10/55

  with preformed cutting elements · CPC title

• E21B10/567

  with preformed cutting elements mounted on a distinct support, e.g. polycrystalline inserts · CPC title

• B24D18/0009 Primary

  using moulds or presses · CPC title

• C04B35/52 Primary

  based on carbon, e.g. graphite · CPC title