Cutter elements, rotary machine tools comprising same and method for making same

Patent metadata

Field	Value
Publication number	US-9393629-B2
Application number	US-201113702036-A
Country	US
Kind code	B2
Filing date	Jun 13, 2011
Priority date	Jun 16, 2010
Publication date	Jul 19, 2016
Grant date	Jul 19, 2016

Abstract

A cutter element ( 100 ) for a rotary machine tool having an axis of rotation, the cutter element comprising a plurality of cutting edges ( 110 ) defined by at least one cutter structure ( 120 ) comprising superhard material, consecutive cutting edges being spaced apart by at most 10 mm and configured operable to cut a body when moved in a direction that is substantially non-aligned with the axis of rotation.

First claim

The invention claimed is:

1. A cutter element for a rotary machine tool having an axis of rotation in use, the cutter element comprising at least three cutting edges configured operable to cut a body when moved in a direction that is substantially non-aligned with the axis of rotation, and defined by at least one cutter structure comprising electro-discharge machine cuttable polycrystalline boron nitride (PCBN) material, the PCBN material comprising at least 80 volume per cent cubic boron nitride grains dispersed in a binder matrix comprising compounds containing cobalt and tungsten, wherein the tool has a lateral cross-section diameter of 10 to 25 mm, and wherein consecutive cutting edges are spaced apart by at most 5 mm azimuthally about the axis of rotation, and wherein the cutter structure is joined to a cemented carbide substrate by an intermediate layer between the cutter structure and the substrate, the intermediate layer comprising grains of metal carbide and grains of cubic boron nitride dispersed in a matrix material.

2. A cutter element as claimed in claim 1 , comprising bi-directional flutes formed into the cutter structure.

3. A cutter element as claimed in claim 1 , for a ball-nosed end mill, in which the cutter structure has a generally domed form.

4. A cutter element as claimed in claim 1 , for an end mill, a routing tool or an edge-trimming tool.

5. A method for making a cutter element as claimed in claim 1 , the method including providing a cylindrical precursor body comprising a tubular superhard structure joined to and surrounding a cemented carbide substrate core; the precursor body having a proximate end, a distal end and a peripheral side connecting the proximate and distal ends, the superhard structure disposed on the peripheral side; and removing portions of the superhard structure from the peripheral side to form a plurality cutting edges on the peripheral side, consecutive cutting edges spaced apart from each other by at most about 10 mm.

6. A method as claimed in claim 5 , including machining the cutter element to form relief and rake face angles of the cutting edge.

7. A method as claimed in claim 5 , including removing portions of the superhard structure and forming a plurality of flutes.

8. A rotary machine tool for milling, reaming or routing;
comprising a cutter element as claimed in claim 1 .

Assignees

• Barry John James
• Fries Robert
• Kasonde Maweja
• Element Six Abrasives Sa

Inventors

• Barry John James
• Fries Robert
• Kasonde Maweja

Classifications

• B23C2226/125

  cubic [CBN] · CPC title

• Y10T407/1946

  Face or end mill · CPC title

• Y10T407/27

  comprising tool of specific chemical composition · CPC title

• B23C5/1081

  with permanently fixed cutting inserts  (B23C5/1018 and B23C5/1063 take precedence) · CPC title

• B23C2226/27

  Composites, e.g. fibre reinforced composites · CPC title