Electrochemical removal of metal or other material from polycrystalline diamond

Patent metadata

Field	Value
Publication number	US-2018111107-A1
Application number	US-201515571285-A
Country	US
Kind code	A1
Filing date	Jun 3, 2015
Priority date	Jun 3, 2015
Publication date	Apr 26, 2018
Grant date	—

Abstract

The present disclosure relates to systems and methods for electrochemical metal or other positive ion removal from polycrystalline diamond (PCD), such as PCD used in earth-boring drill bits. PCD used in the systems and methods described herein has an electrical conductivity-enhanced region.

First claim

What is claimed is:

1 . A system for electrochemically removing a metal or other material from a PCD element, the system comprising:
an anode comprising the PCD element, which PCD element comprises a PCD component comprising the metal or other material and an electrical conductivity-enhanced portion; a cathode; an electrolyte; and a voltage source, wherein, when a voltage is applied to the anode and the cathode by the voltage source, the metal or other material forms a positive ion and is removed from the PCD component to the electrolyte.

2 . The system of claim 1 , wherein the metal comprises a Group VIII metal.

3 . The system of claim 2 , wherein the Group VIII metal comprises cobalt (Co).

4 . The system of claim 1 , wherein the electrical conductivity-enhanced portion comprises at least a portion of a surface of the PCD component.

5 . The system of claim 4 , wherein the electrical conductivity-enhanced portion comprises at least a portion of a top surface of the PCD component.

6 . The system of claim 5 , wherein the electrical conductivity-enhanced portion comprises at least a portion of a side surface of the PCD component.

7 . The system of claim 5 , wherein the electrical conductivity-enhanced portion comprises at least a portion of a top surface, at least a portion of a side surface, and at least a portion of a bottom surface of the PCD component.

8 . The system of claim 1 , wherein the electrical conductivity-enhanced portion comprises substantially all of the PCD component.

9 . The system of claim 1 , wherein the electrolyte is an aqueous electrolyte comprising sulfate (SO 4 2− ), chloride (Cl − ), or nitrate (NO 3 − ), or combinations thereof.

10 . The system of claim 1 , wherein the metal comprises cobalt (Co) and the electrolyte comprises iron (Fe).

11 . The system of claim 1 , wherein at least two metals or other materials form positive ions and are removed from the PCD component to the electrolyte.

12 . The system of claim 1 , wherein the electrical conductivity-enhanced region comprises hydrogen (H) or fluorine (F) or combinations thereof bonded to carbon (C) on a surface of the PCD element, and wherein the electrical conductivity is p type.

13 . The system of claim 12 , wherein the hydrogen (H) or fluorine (F) or combinations thereof are plasma-deposited.

14 . The system of claim 12 , wherein the hydrogen (H) or fluorine (F) or combinations thereof are deposited using a high-temperature annealing process.

15 . The system of claim 1 , wherein the electrical conductivity-enhanced region comprises boron (B), aluminum (Al), phosphorus (P), or lithium (Li) or combinations thereof as doping agent, and wherein the electrical conductivity results from doping.

16 . The system of claim 15 , wherein the boron (B), aluminum (Al), or phosphorus (P), or combinations thereof are implanted in a surface of the PCD component using high dose ion implantation.

17 . The system of claim 15 , wherein the boron (B), aluminum (Al), phosphorus (P), or lithium (Li) or combinations thereof are added to diamond grains contained in the PCD component before formation of the PCD component.

18 . A method of removing a metal or other material from a PCD element comprising:
forming an electrical-conductivity enhanced portion of a PCD component of the PCD element; and conducting an electrochemical process using the PCD element in an anode, wherein, during the electrochemical process, a voltage is applied between the anode and a cathode such that the metal or other material forms a positive ion and is removed from the PCD component by an electrolyte.

19 . The method of claim 18 , wherein forming an electrical conductivity-enhanced portion of the PCD component comprises bonding hydrogen (H) or fluorine (F), or a combination thereof to carbon (C) at a surface of the PCD element to increase p type conductivity.

20 . The method of claim 18 , wherein forming an electrical conductivity-enhanced portion of the PCD component comprises doping the PCD component with boron (B), aluminum (Al), phosphorus (P), or lithium (Li), or a combination thereof.

Assignees

• Halliburton Energy Services Inc

Inventors

• Liang Qi

Classifications

• C25B1/00

  Electrolytic production of inorganic compounds or non-metals · CPC title

• C01P2002/52

  containing elements as dopants · CPC title

• C01B32/28 Primary

  After-treatment, e.g. purification, irradiation, separation or recovery · CPC title

• C25F7/00 Primary

  Constructional parts, or assemblies thereof, of cells for electrolytic removal of material from objects (for both electrolytic coating and removal C25D); Servicing or operating · CPC title

• C25C7/02

  Electrodes (consumable anodes for the refining the metals C25C1/00 - C25C5/00); Connections thereof · CPC title