Cutting tool insert

• US 20070039762A1
• Filed: 05/11/2005
• Published: 02/22/2007
• Est. Priority Date: 05/12/2004
• Status: Active Grant

• Current Assignee: Baker Hughes Holdings LLC (Baker Hughes Company)
• Original Assignee: Baker Hughes Incorporated (Baker Hughes Company)
• Inventors: Achilles, Roy
• Granted Patent: US 7,730,977 B2
• Time in Patent Office: Days
• US Class Current: 175/434
• CPC Class Codes: B23B 2226/315 polycrystalline [PCD]
• CPC Class Codes: B23B 27/148 Composition of the cutting inserts
• CPC Class Codes: C23C 30/005 on hard metal substrates

Abstract

A polycrystalline diamond abrasive cutting element consists generally of a layer of high grade polycrystalline diamond bonded to a cemented carbide substrate. The polycrystalline diamond layer has a working surface and an outer peripheral surface and is characterized by having an annular region or a portion thereof adjacent the peripheral surface that is lean in catalysing material. A region adjacent the working surface is also lean in catalysing material such that in use, as a wear scar develops, both the leading edge and the trailing edge thereof are located in a region lean in catalysing material.

Claims

1. A polycrystalline diamond abrasive element, comprising a layer of polycrystalline diamond bonded to a substrate along an interface, the polycrystalline diamond layer having a working surface opposite the interface and an outer peripheral surface extending between the working surface and the interface, the polycrystalline diamond abrasive element being characterized by having an annular region adjacent the peripheral surface extending away from the working surface, the annular region or a portion thereof being lean in catalysing material.

2. A polycrystalline diamond abrasive element according to claim 1, wherein the polycrystalline diamond layer also has a region adjacent the working surface which is lean in catalysing material.

3. A polycrystalline diamond abrasive element according to claim 1, wherein the lean region(s) extend(s) into the polycrystalline diamond from the peripheral surface and/or working surface to a depth of about 30 μ

m to about 500 μ

m.

4. A polycrystalline diamond abrasive element according to claim 1, wherein the annular region extends from the working surface towards the interface to a depth of at least half the overall thickness of the polycrystalline diamond layer, but stops short of the interface by at least about 500 μ

m.

5. A polycrystalline diamond abrasive element according to claim 1, wherein the polycrystalline diamond layer also has a region rich in catalysing material.

6. A polycrystalline diamond abrasive element according to claim 5, wherein the catalysing material is present as a sintering agent in the manufacture of the polycrystalline diamond layer.

7. A polycrystalline diamond abrasive element according to claim 5, wherein the region rich in catalysing material itself comprises more than one region, which differ in average particle size or chemical composition.

8. A polycrystalline diamond abrasive element according to claim 1, which is a cutting element.

9. A polycrystalline diamond abrasive element according to claim 1, wherein the polycrystalline diamond is of a high grade.

10. A polycrystalline diamond abrasive element according to claim 1, wherein the substrate is a cemented carbide substrate.