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US-12623974-B2 - Method of making a shaped tool component

US12623974B2US 12623974 B2US12623974 B2US 12623974B2US-12623974-B2

Abstract

This disclosure relates to a method of making a shaped tool component from a precursor sintered body comprising polycrystalline diamond (PCD). The sintered body has a PCD table joined to a substrate, and the PCD table varies in depth. The resulting shaped tool component thus also has a PCD layer with varying depth. A method of making a shaped tool component comprising polycrystalline diamond (PCD), comprising the steps: h. Adding a diamond feed stock to a refractory cup; i. Adding a p re-shaped cemented carbide body to the refractory cup adjacent the diamond feed stock; j. Compacting the diamond feed stock and cemented carbide body to form a green body; k. Sintering the green body at a temperature between 1400° C. to 2100° C. and at a pressure of at least 7 GPa, for at least 30 seconds to form a sintered PCD precursor body that comprises a PCD table sinter-joined to the cemented carbide substrate at an interface.

Inventors

  • David Thomas FORD
  • Douglas John GEEKIE

Assignees

  • ELEMENT SIX (UK) LIMITED

Dates

Publication Date
20260512
Application Date
20220405
Priority Date
20210422

Claims (19)

  1. 1 . A method of making a shaped tool component comprising polycrystalline diamond (PCD), comprising the steps: a. Adding a diamond feed stock to a refractory cup; b. Adding a pre-shaped cemented carbide body to the refractory cup adjacent the diamond feed stock; c. Compacting the diamond feed stock and cemented carbide body to form a green body, wherein the compacting occurs at a temperature in the range of 1300° C. and 1500° C. and a pressure in the range of 5 GPa to 8 GPa and wherein a quantity of catalyst present during compacting is insufficient for complete sintering; d. Outgassing the green body; e. Sintering, subsequent to and separate from the compacting, the green body at a temperature between 1400° C. to 2100° C. and at a pressure of at least 7 GPa, for at least 30 seconds to form a sintered PCD precursor body that comprises a PCD table sinter-joined to the cemented carbide substrate at an interface; f. Slicing longitudinally into the sintered PCD precursor body to produce one or more sliced portions of the sintered PCD precursor body, each sliced portion being a tool blank; g. Removing one of said tool blanks from the remainder of the sintered PCD precursor body; and h. Shaping said tool blank into a shaped tool component, in which the thickness of the PCD table in the shaped tool component varies at two or more locations spaced apart laterally on the cemented carbide substrate.
  2. 2 . A method as claimed in claim 1 , in which the thickness of the PCD table in the shaped tool component is between 2 and 20 mm.
  3. 3 . A method as claimed in claim 1 , in which the interface in lateral cross-section comprises a series of interconnected interface segments, the interface segments being any of the following: arcuate, linear, rectilinear.
  4. 4 . A method as claimed in claim 1 , in which the tool blank is planar.
  5. 5 . A method as claimed in claim 1 , in which the tool blank is rectangular cuboidal.
  6. 6 . A method as claimed in claim 1 , in which the tool blank is parallelpiped.
  7. 7 . A method as claimed in claim 1 , in which shaping the tool blank comprises forming a tool profile.
  8. 8 . A method as claimed in claim 7 , in which shaping the tool blank comprises forming a tool profile on or in at least one surface or peripheral edge of the tool blank.
  9. 9 . A method as claimed in claim 8 , in which the tool profile is arranged on or in a peripheral surface of the PCD table.
  10. 10 . A method as claimed in claim 8 , in which the tool profile is arranged wholly within a footprint of the tool blank.
  11. 11 . A method as claimed in claim 7 , in which the tool profile in lateral cross-section comprises a series of interconnected profile segments, the profile segments being any of the following: arcuate, linear, rectilinear, sawtooth, sinusoidal.
  12. 12 . A method as claimed in claim 1 , in which the step of shaping the cemented carbide body and/or the tool blank comprises EDM cutting.
  13. 13 . A method as claimed in claim 1 , in which shaping the cemented carbide body and/or the tool blank comprises laser cutting.
  14. 14 . A method as claimed in claim 1 , comprising shaping the tool blank into an insert for a circular saw.
  15. 15 . A method as claimed in claim 1 , comprising shaping the tool blank into an insert for a dressing wheel.
  16. 16 . A method as claimed in claim 1 , in which the sintered PCD precursor body is cylindrical.
  17. 17 . A method as claimed in claim 2 , in which the interface in lateral cross-section comprises a series of interconnected interface segments, the interface segments being any of the following: arcuate, linear, rectilinear.
  18. 18 . A method as claimed in claim 2 , in which the tool blank is one of planar, rectangular cuboidal, and parallelpiped.
  19. 19 . A method as claimed in claim 3 , in which the tool blank is one of planar, rectangular cuboidal, and parallelpiped.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a § 371 national stage of International Application No. PCT/EP2022/058970, filed Apr. 5, 2022, which claims priority to Great Britain Application No. 2105770.8, filed Apr. 22, 2021. FIELD OF THE INVENTION The present disclosure relates to shaped superhard tool components for cutting wear resistant products, particularly to a method of making said shaped tool components and more particularly to those comprising polycrystalline diamond. BACKGROUND Hard or abrasive workpiece materials, such as metal alloys, ceramics, cermets, certain composite materials and stone may need to be machined using tools having hard or superhard cutting tips. Cemented tungsten carbide is the most widely used tool material for machining hard workpiece materials, and is both hard and tough. Polycrystalline diamond (PCD) and polycrystalline cubic boron nitride (PCBN) are superhard materials, which may be used for machining certain metal alloys widely used in, for example, the automotive industry. Superhard materials are extremely hard and have Vickers hardness of at least about 25 GPa. However, superhard materials are typically less strong and tough than cemented carbide materials and consequently, they may be more prone to fracture and chipping than hard-metals. Superhard tool inserts may comprise a superhard structure bonded to a support substrate (‘backed’), which is most typically formed of cemented tungsten carbide. Tool inserts with complex geometries are not common due to the cost associated with producing and subsequently shaping the PCD. There is a need to develop a more economical way of making shaped tool inserts from PCD. SUMMARY OF THE INVENTION According to the invention, there is provided a method of making a shaped tool component comprising polycrystalline diamond (PCD), comprising the steps: a. Adding a diamond feed stock to a refractory cup;b. Adding a pre-shaped cemented carbide body to the refractory cup adjacent the diamond feed stock;c. Compacting the diamond feed stock and cemented carbide body to form a green body;d. Sintering the green body at a temperature between 1400° C. to 2100° C. and at a pressure of at least 7 GPa, for at least 30 seconds to form a sintered PCD precursor body that comprises a PCD table sinter-joined to the cemented carbide substrate at an interface;e. Slicing longitudinally into the sintered PCD precursor body to produce one or more sliced portions of the sintered PCD precursor body, each sliced portion being a tool blank;f. Removing one of said tool blanks from the remainder of the sintered PCD precursor body; andg. Shaping said tool blank into a shaped tool component, in which the thickness of the PCD table in the shaped tool component varies at two or more locations spaced apart laterally on the cemented carbide substrate. Optional and/or preferable features of the invention are provided in the dependent claims. BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be more particularly described, by way of example only, with reference to the accompanying drawings, in which FIG. 1 is a schematic perspective view of part of a circular saw for cutting wood; FIG. 2 is a schematic side view of a tool insert for use in the circular saw of FIG. 1; FIG. 3 is a schematic flow diagram showing a method of making the tool insert; FIG. 4 is a schematic flow diagram showing an alternative method of making the tool insert; FIG. 5 is a schematic flow diagram showing a yet further alternative method of making the tool insert; FIG. 6 is a schematic perspective view of a first sintered PCD precursor body; FIG. 7 is a side view of the sintered PCD precursor body of FIG. 6, showing in particular a PCD table sinter-joined to a carbide substrate at an interface; FIG. 8 is a front view of the sintered PCD precursor body of FIG. 6; FIG. 9 is a plan view of the sintered PCD precursor body of FIG. 6; FIG. 10 is a schematic side view of a tool blank sliced from the sintered PCD precursor body of FIG. 6, with a superimposed tool profile, showing in particular the excess material of the PCD table intended for removal; FIG. 11 is a schematic side view of the shaped tool component of FIG. 10 after the excess material has been removed; FIG. 12 is a schematic perspective view of a second sintered PCD precursor body; FIG. 13 is a side view of the sintered PCD precursor body of FIG. 12; FIG. 14 is a front view of the sintered PCD precursor body of FIG. 12; FIG. 15 is a plan view of the sintered PCD precursor body of FIG. 12; FIG. 16 is a schematic side view of a tool blank sliced from the sintered PCD precursor body of FIG. 12, with a different superimposed tool profile, showing in particular the excess material of the PCD table intended for removal; FIG. 17 is a schematic side view of the shaped tool component of FIG. 16 after the excess material has been removed; FIGS. 18a to 18c are a set of three schematics illustrating the shaping of an L-shaped partial