WO2019129711A1 - Constructions extra-dures et leurs procédés de fabrication - Google Patents

Constructions extra-dures et leurs procédés de fabrication Download PDF

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Publication number
WO2019129711A1
WO2019129711A1 PCT/EP2018/086593 EP2018086593W WO2019129711A1 WO 2019129711 A1 WO2019129711 A1 WO 2019129711A1 EP 2018086593 W EP2018086593 W EP 2018086593W WO 2019129711 A1 WO2019129711 A1 WO 2019129711A1
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WIPO (PCT)
Prior art keywords
super hard
region
grains
polycrystalline
diamond
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PCT/EP2018/086593
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English (en)
Inventor
Dong Wang
Original Assignee
Element Six (Uk) Limited
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Publication date
Application filed by Element Six (Uk) Limited filed Critical Element Six (Uk) Limited
Priority to US16/762,831 priority Critical patent/US20200269321A1/en
Publication of WO2019129711A1 publication Critical patent/WO2019129711A1/fr

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    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B10/00—Drill bits
    • E21B10/46—Drill bits characterised by wear resisting parts, e.g. diamond inserts
    • E21B10/56—Button-type inserts
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/515—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics
    • C04B35/52—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics based on carbon, e.g. graphite
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
    • B22F3/12—Both compacting and sintering
    • B22F3/14—Both compacting and sintering simultaneously
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
    • B22F3/24—After-treatment of workpieces or articles
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F7/00—Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting wherein at least one part is obtained by sintering or compression
    • B22F7/06—Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting wherein at least one part is obtained by sintering or compression of composite workpieces or articles from parts, e.g. to form tipped tools
    • C—CHEMISTRY; METALLURGY
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    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/515—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics
    • C04B35/52—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics based on carbon, e.g. graphite
    • C04B35/528—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics based on carbon, e.g. graphite obtained from carbonaceous particles with or without other non-organic components
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    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
    • C04B35/628—Coating the powders or the macroscopic reinforcing agents
    • C04B35/62802—Powder coating materials
    • C04B35/62828—Non-oxide ceramics
    • C04B35/62836—Nitrides
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    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/64—Burning or sintering processes
    • C04B35/645—Pressure sintering
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C26/00—Alloys containing diamond or cubic or wurtzitic boron nitride, fullerenes or carbon nanotubes
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C29/00—Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides
    • C22C29/02—Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides based on carbides or carbonitrides
    • C22C29/06—Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides based on carbides or carbonitrides based on carbides, but not containing other metal compounds
    • C22C29/08—Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides based on carbides or carbonitrides based on carbides, but not containing other metal compounds based on tungsten carbide
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B10/00—Drill bits
    • E21B10/46—Drill bits characterised by wear resisting parts, e.g. diamond inserts
    • E21B10/56—Button-type inserts
    • E21B10/567—Button-type inserts with preformed cutting elements mounted on a distinct support, e.g. polycrystalline inserts
    • E21B10/573—Button-type inserts with preformed cutting elements mounted on a distinct support, e.g. polycrystalline inserts characterised by support details, e.g. the substrate construction or the interface between the substrate and the cutting element
    • E21B10/5735—Interface between the substrate and the cutting element
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
    • B22F3/24—After-treatment of workpieces or articles
    • B22F2003/241—Chemical after-treatment on the surface
    • B22F2003/242—Coating
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F5/00—Manufacture of workpieces or articles from metallic powder characterised by the special shape of the product
    • B22F2005/001—Cutting tools, earth boring or grinding tool other than table ware
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F2998/00—Supplementary information concerning processes or compositions relating to powder metallurgy
    • B22F2998/10—Processes characterised by the sequence of their steps
    • C—CHEMISTRY; METALLURGY
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    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
    • C04B2235/3231—Refractory metal oxides, their mixed metal oxides, or oxide-forming salts thereof
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    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
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    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/38—Non-oxide ceramic constituents or additives
    • C04B2235/3804—Borides
    • C04B2235/3813—Refractory metal borides
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    • C04B2235/3817—Carbides
    • C04B2235/3839—Refractory metal carbides
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    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
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    • C04B2235/38—Non-oxide ceramic constituents or additives
    • C04B2235/3852—Nitrides, e.g. oxynitrides, carbonitrides, oxycarbonitrides, lithium nitride, magnesium nitride
    • C04B2235/3886—Refractory metal nitrides, e.g. vanadium nitride, tungsten nitride
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    • C22C26/00—Alloys containing diamond or cubic or wurtzitic boron nitride, fullerenes or carbon nanotubes
    • C22C2026/007—Alloys containing diamond or cubic or wurtzitic boron nitride, fullerenes or carbon nanotubes with additional metal compounds being nitrides

Definitions

  • This disclosure relates to superhard constructions and methods of making such constructions, particularly but not exclusively to constructions comprising polycrystalline diamond (PCD) structures attached to a substrate, and tools comprising the same, particularly but not exclusively for use in rock degradation or drilling, or for boring into the earth.
  • PCD polycrystalline diamond
  • Polycrystalline super hard materials such as polycrystalline diamond (PCD) and polycrystalline cubic boron nitride (PCBN) may be used in a wide variety of tools for cutting, machining, drilling or degrading hard or abrasive materials such as rock, metal, ceramics, composites and wood-containing materials.
  • tool inserts in the form of cutting elements comprising PCD material are widely used in drill bits for boring into the earth to extract oil or gas.
  • the working life of super hard tool inserts may be limited by fracture ofthe super hard material, including by spalling and chipping, or by wear of the tool insert.
  • Cutting elements such as those for use in rock drill bits or other cutting tools typically have a body in the form of a substrate which has an interface end/surface and a super hard material which forms a cutting layer bonded to the interface surface of the substrate by, for example, a sintering process.
  • the substrate is generally formed of a tungsten carbide-cobalt alloy, sometimes referred to as cemented tungsten carbide and the super hard material layer is typically polycrystalline diamond (PCD), polycrystalline cubic boron nitride (PCBN) or a thermally stable product TSP material such as thermally stable polycrystalline diamond.
  • PCD polycrystalline diamond
  • PCBN polycrystalline cubic boron nitride
  • TSP material thermally stable product
  • PCD Polycrystalline diamond
  • PCD material is an example of a super hard material (also called a superabrasive material or ultra hard material) comprising a mass of substantially inter-grown diamond grains, forming a skeletal mass defining interstices between the diamond grains.
  • PCD material typically comprises at least about 80 volume % of diamond and is conventionally made by subjecting an aggregated mass of diamond grains to an ultra-high pressure of greater than about 5 GPa, and temperature of at least about 1 ,200°C, for example.
  • a material wholly or partly filling the interstices may be referred to as filler or binder material.
  • PCD is typically formed in the presence of a sintering aid such as cobalt, which promotes the inter-growth of diamond grains.
  • a sintering aid such as cobalt
  • Suitable sintering aids for PCD are also commonly referred to as a solvent-catalyst material for diamond, owing to their function ofdissolving, to some extent, the diamond and catalysing its re-precipitation.
  • a solvent-catalyst for diamond is understood be a material that is capable of promoting the growth of diamond or the direct diamond-to-diamond inter-growth between diamond grains at a pressure and temperature condition at which diamond is thermodynamically stable. Consequently the interstices within the sintered PCD product may be wholly or partially filled with residual solvent-catalyst material.
  • PCD is often formed on a cobalt-cemented tungsten carbide substrate, which provides a source of cobalt solvent-catalyst for the PCD.
  • PCD polycrystalline diamond
  • the thermal degradation increases the wear rate of the cutter through increased cracking and spalling ofthe PCD layer as well as back conversion of the diamond to graphite causing increased abrasive wear.
  • the high temperatures incurred during operation cause the residual binder-catalyst, e.g. cobalt, in the diamond matrix to thermally expand.
  • thermally stable polycrystalline diamond construction be engineered in a manner that not only displays improved thermal characteristics, when compared to conventional PCD, but also has improved fracture toughness without adversely affecting the material’s high strength and abrasion resistance.
  • a super hard polycrystalline construction comprising:
  • a first region comprising a body of thermally stable polycrystalline super hard material having an exposed surface forming a working surface, and a peripheral side edge, said polycrystalline super hard material comprising a plurality of intergrown grains of super hard material;
  • the third region extends across a surface of the second region along an interface, the third region comprising a composite material having a first phase comprising a plurality of non-intergrown diamond grains, the majority of said diamond grains having a coating comprising nano-sized cBN particles.
  • a method of forming a super hard polycrystalline construction comprising: forming a pre-sinter assembly comprising:
  • a further mass comprising diamond grains or particles coated with nano-sized cBN particles;
  • the pre-sinter assembly at an ultra-high pressure of around 5 GPa or greater and a temperature to bond together the grains of super hard material in the first mass to form a first region comprising a body of interbonded polycrystalline super hard material bonded to a further region formed of substantially non-interbonded grains or particles of the super hard material in the further mass; the further region being bonded to the substrate along an interface, the further region forming an intermediate region between the first region and the substrate and comprising a diamond composite material comprising a plurality of non-intergrown diamond grains having a coating of nan-sized cBN particles.
  • a tool comprising the superhard polycrystalline construction defined above, the tool being for cutting, milling, grinding, drilling, earth boring, rock drilling or other abrasive applications.
  • the tool may comprise, for example, a drill bit for earth boring or rock drilling, a rotary fixed-cutter bit for use in the oil and gas drilling industry, or a rolling cone drill bit, a hole opening tool, an expandable tool, a reamer or other earth boring tools.
  • a drill bit or a cutter or a component therefor comprising the superhard polycrystalline construction defined above.
  • Figure 1 is a perspective view of an example of a conventional PCD cutter element or construction for a drill bit for boring into the earth;
  • Figure 2 is a schematic cross-section of a conventional portion of a PCD microstructure with interstices between the inter-bonded diamond grains filled with a nondiamond phase material;
  • Figure 3 is a schematic cross-section of a first example of a superhard construction
  • Figure 4 is a schematic cross-section of a second example of a superhard construction
  • Figure 5 is a schematic cross-section of a third example of a superhard construction
  • Figure 6 is a schematic cross-section of a fourth example of a superhard construction
  • Figure 7 is a schematic plan view of the superhard construction of Figure 5;
  • Figure 8 is a schematic plan view of the superhard construction of Figure 6;
  • Figure 9 is a is a schematic alternative plan view of the superhard construction of Figure 5.
  • Figure 10 is a schematic cross-section of a sixth example of a super hard construction.
  • a“superhard material” is a material having a Vickers hardness of at least about 28 GPa. Diamond and cubic boron nitride (cBN) material are examples of superhard materials.
  • a“superhard construction” means a construction comprising a body of polycrystalline superhard material. In such a construction, a substrate may be attached thereto.
  • polycrystalline diamond is a type of polycrystalline superhard (PCS) material comprising a mass of diamond grains, a substantial portion of which are directly inter-bonded (intergrown) with each other and in which the content of diamond is at least about 80 volume percent of the material.
  • PCS polycrystalline superhard
  • interstices between the diamond grains may be at least partly filled with a binder material comprising a catalyst for diamond.
  • “interstices” or“interstitial regions” are regions between the diamond grains of PCD material.
  • A“catalyst material” for a superhard material is capable of promoting the growth or sintering of the superhard material.
  • substrate as used herein means any substrate over which the superhard material layer is formed.
  • a “substrate” as used herein may be a transition layer formed over another substrate.
  • integralally formed means regions or parts are produced contiguous with each other and are not separated by a different kind of material.
  • the term“super hard composite” means a composite material formed of substantially non-intergrown grains of super hard material in a matrix of binder phase material, for example less than 3% of the grains of super hard material are intergrown, and in some instances none of the super hard grains are intergrown. Whether or not the super hard grains are intergrown may be determined using conventional methods of SEM or X-ray analysis of images taken of the construction. In addition, for a substantially non-intergrown structure, the wear resistance of the material will be substantially less (that is, worse) than sintered polycrystalline diamond material having the same average grain size of diamond grains as the super hard grains in the composite structure. This may be confirmed using conventional tests such as a vertical borer test of the material.
  • Figure 1 is a schematic view of an example of a conventional PCD super hard construction such as a cutting element 1 which includes a substrate 3 with a layer of superhard material 2 formed on the substrate 3.
  • the substrate 3 may be formed of a hard material such as cemented tungsten carbide.
  • the superhard material 2 may be, for example, high density polycrystalline diamond (PCD) comprising at least 80 vol% of interbonded (intergrown) diamond grains.
  • the cutting element 1 may be mounted into a bit body such as a drag bit body (not shown) and may be suitable, for example, for use as a cutter insert for a drill bit for boring into the earth.
  • the exposed top surface of the superhard material opposite the substrate forms the cutting face 4, also known as the working surface, which is the surface which, along with its edge 6, performs the cutting in use.
  • the substrate 3 is generally cylindrical and has a peripheral surface 10 and a peripheral top edge 12.
  • the working surface or“rake face” 4 of the polycrystalline composite construction 1 is the surface or surfaces over which the chips of material being cut flow when the cutter is used to cut material from a body, the rake face 4 directing the flow of newly formed chips.
  • This face 4 is commonly also referred to as the top face or working surface of the cutting element as the working surface 4 is the surface which, along with its edge 6, is intended to perform the cutting of a body in use.
  • the term“cutting edge”, as used herein, refers to the actual cutting edge, defined functionally as above, at any particular stage or at more than one stage of the cutter wear progression up to failure of the cutter, including but not limited to the cutter in a substantially unworn or unused state.
  • chips are the pieces of a body removed from the work surface of the body being cut by the polycrystalline composite construction 1 in use.
  • a“wear scar” is a surface of a cutter formed in use by the removal of a volume of cutter material due to wear of the cutter.
  • a flank face may comprise a wear scar.
  • material may progressively be removed from proximate the cutting edge, thereby continually redefining the position and shape of the cutting edge, rake face and flank as the wear scar forms.
  • the substrate 3 is typically formed of a hard material such as a cemented carbide material, for example, cemented tungsten carbide.
  • the interstices 24 between the inter-bonded grains 22 of super hard material such as diamond grains in the case of PCD may be at least partly filled with a non-super hard phase material.
  • This non-super hard phase material also known as a filler material may comprise residual catalyst/binder material, for example cobalt.
  • Figures 3 to 10 are schematic cross-sections through examples of super hard constructions which may have the same outer shape as the construction 1 of Figure
  • the superhard construction 30 includes a layer or region of super hard material 34 forming the rake face or cutting surface 4 and having the cutting edge 6, a substrate 32 and a region 36 intermediate the layer of superhard material 34 and the substrate 32.
  • the interface 37 between the substrate and the intermediate region 36 has at least a portion having an uneven topology. This may be interpreted as, but not limited to, covering one or more of the surface being non-uniform, varying, irregular, rugged, not level, and/or not smooth, and/or with peaks and troughs.
  • the interface 38 between the layer of super hard material 34 and the intermediate region 36 is substantially non-planar.
  • the intermediate region 36 does not form part of the working surface but is spaced therefrom by a region of the super hard material 34. Additionally, the intermediate region 36 of super hard composite material extends across the interface 37 with the substrate 32 and spaces the super hard layer 34 from the substrate 32.
  • the example of a super hard construction 40 shown in Figure 4 differs from that shown in Figure 3 in that the interface 48 between the layer of super hard material 44 and the intermediate region 46 is substantially planar.
  • FIG. 5 differs from that shown in Figure 3 in that an intermediate region 56 of a composite material formed of non-interbonded grains of super hard material, such as diamond grains, that is interposed between a substrate 52 and layer of super hard material 54 extends to and forms part of the working surface 4 of the super hard construction 50.
  • the interface 57 between the intermediate region 56 and the substrate 52 has at least a portion having an uneven topology and the interface 58 between the intermediate region 56 and the layer of super hard material 54 is also substantially non-planar, the interface 58 being concavely arcuate.
  • Figure 6 is an example similar to that shown in Figure 5 with the exception that the interface 68 between the region or layer of polycrystalline super hard material 64 and the intermediate region 68 is sloped outwardly from the working surface towards the substrate 62 rather than concavely curved, and that is shown by the inclined plane depicted in in cross section in Figure 6, the intermediate region 66 thereby comprising a truncated cone projecting from the substrate 62 and extending through the layer or region of super hard material 64 to the cutting face, forming part of the working surface of the super hard construction 60.
  • Figure 7 shows the example construction of Figure 5 in plan view and it will be seen that the super hard region or layer 54 forms an annular portion around the outer peripheral surface of the intermediate region of composite material 56.
  • the super hard layer or region 54 may form an annular portion around the outer peripheral surface of the intermediate region 56 of composite material, or the layer or region of super hard material 64 may be in the form of segments interposed around the cutting edge with the intermediate region 64.
  • the advantage of such a construction may be that the construction may be rotatable after use such that a different cutting edge may be presented to the surface to be cut and also the segments may act to confine damage to a limited area of the construction during use.
  • the interface 76 between the intermediate region 74 and the layer of super hard material 72 may be ridged or grooved, such ridges or grooves extending, for example, from the cutting face 4 to the flank face of the construction.
  • the intermediate region may have the general structure of that shown in Figures 5 and 6 but may not extend all the way to or form part of the working surface.
  • the intermediate region may extend to a distance of around 0.5mm or less from the working surface.
  • the super hard construction 90 comprises a substrate 92, a layer of super hard material 94 and an intermediate region 96 between the layer of super hard material 94 and the substrate 92 spacing the layer of super hard material 94 from the substrate 92.
  • the interface 97 between the substrate and the intermediate region 96 has at least a portion having an uneven topology and the interface 98 between the intermediate region 96 and the layer of super hard material 94 is also substantially non-planar, and may comprise one or more grooves or ridges to provide an interlocking fit between the two layers.
  • the layer or region of super hard material 34, 44, 54, 64, 74 94, prior to final processing and directly after sintering may for example have a micro-structure with interstices between the inter-bonded grains of super hard material filled with a non- super hard phase material such as that shown in the representation of conventional PCD in Figure 2.
  • the super hard grains being diamond
  • the interstitial spaces between inter-bonded diamond grains are substantially free of accessible residual solvent catalyst that would otherwise be present in the interstitial spaces and the layer or region of super hard material 34, 44, 54, 64, 74, 94, is considered to be fully leached thermally stable PCD.
  • the super hard material of the various examples used to form the layer or region of super hard material 34, 44, 54, 64, 74, 94 may be, for example, polycrystalline diamond (PCD) and/or polycrystalline cubic boron nitride (PCBN) and/or lonsdaleite and the super hard particles or grains may be of natural and/or synthetic origin.
  • PCD polycrystalline diamond
  • PCBN polycrystalline cubic boron nitride
  • lonsdaleite and/or lonsdaleite
  • the super hard particles or grains may be of natural and/or synthetic origin.
  • the substrate of the examples, 32, 42, 52, 62, 72, 92 may be formed of a hard material such as a cemented carbide material and may include, for example, cemented tungsten carbide, cemented tantalum carbide, cemented titanium carbide, cemented molybdenum carbide or mixtures thereof.
  • the binder metal for such carbides suitable for forming the substrate 32, 42, 52, 62, 72, 92 may be, for example, nickel, cobalt, iron or an alloy containing one or more of these metals and may include additional elements or compounds of other materials such as chromium, or vanadium. This binder may, for example, be present in an amount of 10 to 20 mass %, but this may be as low as 6 mass % or less.
  • the layer or region of polycrystalline super hard material 34, 44, 54, 64, 74 94 may be a high density PCD formed of more than 95 vol% of diamond.
  • a PCD body may be formed using known methods such as by sintering the diamond grains at sintering pressures of around 8GPa and above, as described in US patent application published as US 2010/0084196.
  • the layer or region of polycrystalline super hard material 34, 44, 54, 64, 74, 94 may be formed of high density PCD comprising a sintered mass of nano diamond grains as set out in US patent application published as US2005/0191 14.
  • high density or binderless PcBN, and PcBN constructions formed from nanomaterials may also be formed according to known methods.
  • the layer or region of super hard material 34, 44, 54, 64, 74, 94 may comprise PCBN.
  • Components comprising PCBN are used principally for machining metals.
  • PCBN material comprises a sintered mass of cubic boron nitride (cBN) grains.
  • the cBN content of PCBN materials may be at least about 40 volume %. When the cBN content in the PCBN is at least about 70 volume % there may be substantial direct contact among the cBN grains. When the cBN content is in the range from about 40 volume % to about 60 volume % of the compact, then the extent of direct contact among the cBN grains is limited.
  • PCBN may be made by subjecting a mass of cBN particles together with a powdered matrix phase, to a temperature and pressure at which the cBN is thermodynamically more stable than the hexagonal form of boron nitride, hBN.
  • PCBN is less wear resistant than PCD which may make it suitable for different applications to that of PCD.
  • a PCD or PCBN grade is a PCD or PCBN material characterised in terms of the volume content and size of diamond grains in the case of PCD or cBN grains in the case of PCBN, the volume content of interstitial regions between the grains, and composition of material that may be present within the interstitial regions.
  • a grade of super hard material may be made by a process including providing an aggregate mass of super hard grains having a size distribution suitable for the grade, optionally introducing catalyst material or additive material into the aggregate mass, and subjecting the aggregated mass in the presence of a source of catalyst material for the super hard material to a pressure and temperature at which the super hard grains are more thermodynamically stable than graphite (in the case of diamond) or hBN (in the case of CBN), and at which the catalyst material is molten. Under these conditions, molten catalyst material may infiltrate from the source into the aggregated mass and is likely to promote direct intergrowth between the diamond grains in a process of sintering, to form a polycrystalline super hard structure.
  • the aggregate mass may comprise loose super hard grains or super hard grains held together by a binder material. In the context of diamond, the diamond grains may be natural or synthesised diamond grains.
  • Different grades of super hard material such as polycrystalline diamond may have different microstructures and different mechanical properties, such as elastic (or Young’s) modulus E, modulus of elasticity, transverse rupture strength (TRS), toughness (such as so-called KiC toughness), hardness, density and coefficient of thermal expansion (CTE).
  • Different PCD grades may also perform differently in use. For example, the wear rate and fracture resistance of different PCD grades may be different.
  • the layer or region 34, 44, 54, 64, 74, 94, of polycrystalline super hard material shown in the cutter elements 30, 40, 50, 60, 70 90 of Figures 3 to 10 may comprise, for example, one or more grades of super hard material and may comprise one or more layers of super hard material which may differ in, for example, grain size and/or composition of the super hard material.
  • the grains of super hard material may be, for example, diamond grains or particles.
  • the feed comprises a mixture of a coarse fraction of diamond grains and a fine fraction of diamond grains.
  • the coarse fraction may have, for example, an average particle/grain size ranging from about 10 to 60 microns.
  • average particle or grain size it is meant that the individual particles/grains have a range of sizes with the mean particle/grain size representing the "average”.
  • the average particle/grain size ofthe fine fraction is less than the size of the coarse fraction.
  • the fine fraction may have an average grain size of between around 1 /10 to 6/10 of the size of the coarse fraction, and may, in some examples, range for example between about 0.1 to 20 microns.
  • the weight ratio of the coarse diamond fraction to the fine diamond fraction may range from about 50% to about 97% coarse diamond and the weight ratio of the fine diamond fraction may be from about 3% to about 50%. In other embodiments, the weight ratio of the coarse fraction to the fine fraction may range from about 70:30 to about 90:10.
  • the weight ratio of the coarse fraction to the fine fraction may range for example from about 60:40 to about 80:20.
  • the particle size distributions of the coarse and fine fractions do not overlap and in some embodiments the different size components of the compact are separated by an order of magnitude between the separate size fractions making up the multimodal distribution.
  • Some examples consist of a wide bi-modal size distribution between the coarse and fine fractions of super hard material, but some examples may include three or even four or more size modes which may, for example, be separated in size by an order of magnitude, for example, a blend of particle sizes whose average particle size is 20 microns, 2 microns, 200nm and 20nm.
  • Sizing of diamond particles/grains into fine fraction, coarse fraction, or other sizes in between, may be through known processes such as jet-milling of larger diamond grains and the like.
  • the cemented metal carbide substrate 32, 42, 52, 62, 72, 92 may, for example, be conventional in composition and, thus, may include any of the Group IVB, VB, or VIB metals, which are pressed and sintered in the presence of a binder of cobalt, nickel or iron, or alloys thereof.
  • the metal carbide is tungsten carbide.
  • the intermediate region 36, 46, 56, 66, 76, 96 is a composite material formed of non- interbonded grains of diamond material, coated with nano-sized cBN particles, and a matrix material.
  • the matrix material further comprises a second phase such as a material that has a lower hardness than the hardness of the diamond grains.
  • the additional hard material may, for example be any one or more of cBN, WC, wBN and the like.
  • the matrix material of the intermediate region may comprise cobalt and/or any one or more alloys or compounds of any one or more transition metals including titanium, zirconium, vanadium, hafnium, tantalum, niobium, chromium, molybdenum, tungsten, copper, cobalt, nickel, iron, and/or manganese.
  • the one or more alloys or compounds may, for example be any one or more oxides, nitrides, carbides, carbonitrides, and/or oxycarbides of said transition metals.
  • the matrix material comprises aluminium, and/or nickel and/or one or more alloys or compounds thereof.
  • the matrix material of the intermediate region comprises any one or more of titanium carbon itride, titanium diboride, aluminium nitride, aluminium oxide, cobalt, and tungsten carbide, or alloys or compounds thereof.
  • the matrix material comprises between around 5 vol% to around 80 vol% of the material of the intermediate region, and in some examples comprises between around 5 to 60 vol% thereof, or between around 10 vol% to around 30 vol% thereof.
  • the super hard grains in the intermediate region comprise between around 30 vol% to around 70 vol% ofthe material of the intermediate region.
  • the grains of super hard material in the intermediate region together with any additional phase to the matrix material comprises between around 20vol% to around 95 vol% of the material of the intermediate region, and in some examples may be between around 70vol% to around 90 vol% thereof, or between around 50vol% to around 90 vol% thereof, or between around 30vol% to around 90 vol% thereof.
  • the materials forming the layer or region of super hard material, the intermediate region and the substrate all have an associated hardness and, in some examples, the hardness of the intermediate region is greater than the hardness of the substrate and less than the hardness of the layer or region of super hard material.
  • the intermediate region may comprise two or more layer or regions differing in composition and/or construction, such as multiple layers of composite material having at least the characteristic of non intergrown or non- interbonded grains of super hard material coated with nano-sized cBN particles.
  • the depth of the layer or region of super hard material 34, 44, 54, 64, 74, 94 from the working surface along the peripheral side edge of the respective construction 30, 40, 50, 60, 70 90 may, for example, be at least around 0.3 mm or greater, such as between around 0.3mm to around 6.5mm. Additionally, in some embodiments, the thickness of the intermediate region 36, 46, 56, 66, 76, 96 along a plane parallel to the longitudinal axis of the construction may be at least 0.05 mm, for example between around 0.1 mm to around 4 mm, between around 0.3 to around 1 mm, or between around 0.5mm to around 0.8 mm.
  • the thickness of the cBN coating on the diamond grains in the intermediate region 36, 46, 56, 66, 76, 96 is between around 100nm to around 800nm, in some examples it is around 200nm to around 400nm.
  • the concentration of super hard grains in the intermediate region may be graded from the interface with the layer or region of super hard material to the substrate.
  • the layer or region of super hard material comprises substantially no constituents of the matrix material of the intermediate region.
  • the layer or region of super hard material 34, 44, 54, 64, 72, 84, 94 comprises a thermally stable material such as thermally stable PCD, and, if the super hard material comprises diamond grains, may have a diamond content between around 80 volume % to around 100 volume %.
  • the thermally stable layer of superhard material may, for example, be substantially free of all accessible catalyst material for diamond, said region forming the thermally stable first region, and may, for example comprise at most around 3 weight percent of catalyst material for diamond.
  • the layer of thermally stable super hard material comprises binderless PCD material and/or CVD diamond and/or a polycrystalline super hard material formed from nanodiamond grains.
  • the intermediate region 36, 46, 56, 66, 86, 96 may be bonded to the layer of superhard material and/or to a further intermediate region, and/or to the substrate 32, 42, 52, 62, 82, 92 by a brazed joint and/or a sintered joint along the respective interfaces.
  • the grains of superhard material used for making the thermally stable superhard layer 34, 44, 54, 64, 84, 94 may be, for example, diamond grains or particles, or for example, lonsdaleite or cBN grains or particles.
  • the starting mixture prior to sintering they may be, for example, bimodal, that is, the feed comprises a mixture of a coarse fraction of superhard grains and a fine fraction of superhard grains.
  • the binder catalyst/solvent used to assist in the bonding of the grains of superhard material such as diamond grains in the sintering process may comprise cobalt or some other iron group elements, such as iron or nickel, or an alloy thereof.
  • Carbides, nitrides, borides, and oxides of the metals of Groups IV-VI in the periodic table are other examples of non-diamond material that might be added to the sinter mix.
  • the binder/catalyst/sintering aid may be Co.
  • the super hard constructions of the examples shown in Figures 3 to 10 may be fabricated, for example, as follows.
  • the substrate and intermediate region(s) may be pre-formed.
  • the substrate may be pre-formed by pressing the green body of grains of hard material such as tungsten carbide into the desired shape, including the interface features at one free end thereof, and sintering the green body to form the substrate element.
  • the substrate interface features may be machined from a sintered cylindrical body of hard material, to form the desired geometry for the interface features.
  • the substrate may, for example, comprise WC particles bonded with a catalyst material such as cobalt, nickel, or iron, or mixtures thereof.
  • the intermediate region may be prepared as follows. A mass of nano-sized cBN particles having, for example, an average particle size of around 200 nm is obtained.
  • cBN nano particles are dispersed into 50 ml of an aqueous solution containing 0.05 % polyvinyl alcohol (PVA, Mw 40K).
  • An ultrasonic probe is introduced to disperse the cBN nano particles.
  • Once fully dispersed around 10 g of diamond grits are then added into the dispersion.
  • the mixture is then freeze dried or spray dried following a heat treatment at 160 °C for 2 hrs to coat the diamond grits with the cBN nano particles.
  • the process may be repeated for example a further two to five times to obtain well coated diamond grains. SEM imaging may be used to determine the quality of the coating.
  • a green body for the superhard construction which comprises the pre-formed substrate, a mass of diamond grains coated with the nano-sized cBN particles to form the intermediate region and the particles of superhard material such as diamond particles or cubic boron nitride particles, may be placed onto the substrate, to form a pre-sinter assembly which may be encapsulated in a capsule for an ultra-high pressure furnace, as is known in the art.
  • the substrate may be placed first into the canister followed by the coated diamond grains and then the superabrasive particles, for example in powder form, to form the super abrasive layer, are placed inside a metal cup formed, for example, of niobium, tantalum, or titanium.
  • the super abrasive grains for the super abrasive layer may be placed into the cup first followed by the coated diamond grains and the pre-formed substrate.
  • the contents of the cup are then hydrostatically pressed into the superhard powder such that the requisite powder mass is pressed around the interface features of the preformed carbide substrate to form the pre-composite.
  • the pre-composite is then outgassed at about 1050 degrees C.
  • the pre-composite is closed by placing a second cup at the other end and the pre-composite is sealed by cold isostatic pressing or EB welding.
  • the pre-composite is then sintered to form the sintered body.
  • the superhard grains for the super abrasive layer may be diamond grains and the substrate may be cobalt-cemented tungsten carbide.
  • the pre-sinter assembly may comprise an additional source of catalyst material such as a disc containing catalyst material such as cobalt which may be placed adjacent the diamond grains in the pre-composite assembly.
  • the binder catalyst/solvent used in the initial pre-sinter mixture may comprise cobalt or some other iron group elements, such as iron or nickel, or an alloy thereof. Carbides, nitrides, borides, and oxides of the metals of Groups IV- VI in the periodic table are other examples of non-diamond material that might be added to the sinter mix.
  • the binder/catalyst/sintering aid may be Co.
  • the method may include loading the capsule comprising a pre-sinter assembly into a press and subjecting the green body to an ultra-high pressure and a temperature at which the superhard material is thermodynamically stable to sinter the superhard grains.
  • the green body may comprise diamond grains and the pressure to which the assembly is subjected is at least about 5 GPa and the temperature is at least about 1 ,300 degrees centigrade. In some examples, the pressure to which the assembly may be subjected is around 5.5-6 GPa, but in some examples it may be around 7.7GPa or greater. Also, in some examples, the temperature used in the sintering process may be in the range of around 1400 to around 1500 degrees C.
  • the polycrystalline super hard constructions may be ground to size and may include, if desired, a 45° chamfer of , for example, approximately 0.4mm height on the body of polycrystalline super hard material so produced.
  • solvent / catalyst for the diamond grains may be introduced by various methods, including admixing or blending solvent / catalyst material in powder form with the diamond grains, depositing solvent / catalyst material onto surfaces of the diamond grains, or infiltrating solvent / catalyst material into the aggregated mass from a source of the material, either prior to the sintering step or as part of the sintering step, for example from the substrate.
  • CVD chemical vapour deposition
  • PVD physical vapour deposition
  • ALD atomic layer deposition
  • the binder/catalyst such as cobalt may be deposited onto surfaces of the diamond grains which are to form the superabrasive layer (as opposed to the intermediate region) by first depositing a pre-cursor material and then converting the precursor material to a material that comprises elemental metallic cobalt.
  • cobalt carbonate may be deposited on the diamond grain surfaces using the following reaction:
  • the deposition of the carbonate or other precursor for cobalt or other solvent / catalyst for diamond may be achieved by means of a method described in PCT patent publication number WO/2006/032982.
  • the cobalt carbonate may then be converted into cobalt and water, for example, by means of pyrolysis reactions such as the following:
  • cobalt powder or precursor to cobalt such as cobalt carbonate
  • a precursor to a solvent / catalyst such as cobalt
  • the cemented carbide substrate may be formed of tungsten carbide particles bonded together by the binder material, the binder material comprising an alloy of Co, Ni and Cr.
  • the tungsten carbide particles may form at least 70 weight percent and at most 95 weight percent of the substrate.
  • the binder material may comprise between about 10 to 50 wt.% Ni, between about 0.1 to 10 wt.% Cr, and the remainder weight percent comprises Co.
  • the super hard constructions of Figures 3 to 10 may be formed as follows.
  • the coated diamond grains which are to form the intermediate region were made by placing 0.5 gram cBN nano particles having, for example, an average particle size of around 200 nm are dispersed in 50 ml of an aqueous solution containing 0.05 % polyvinyl alcohol (PVA, Mw 40 K). An ultrasonic probe is introduced to disperse the cBN nano particles. Once fully dispersed, around 10 g of diamond grits are then added into the dispersion. The mixture is then freeze dried or spray dried following a heat treatment at 160 °C for 2 hrs to coat the diamond grits with the cBN nano particles. The process may be repeated for example up to around five times to obtain well coated diamond grains.
  • PVA polyvinyl alcohol
  • the dried powder comprising the coated diamond grains was sieved to form a precomposite for the intermediate region.
  • diamond powder with an average grain size of about 19 microns was mixed in a planetary ball mill for about 1 hour with 1wt% Co using methanol media and tungsten carbide milling balls. After mixing, the powder was sieved and dried in a rota vapour apparatus to remove the methanol and WC balls. The dried powder was then returned to the planetary ball mill for about 5 minutes to remove agglomerates before being sieved again.
  • the pre-composite for the intermediate region was then placed on top of a cemented tungsten carbide substrate shaped to provide an interface between the substrate and the intermediate region at least a portion of which has an uneven topology.
  • the substrate is also shaped to have a recess therein to receive both the pre-composite for the intermediate region and the diamond powder to form the PCD layer, the substrate extending around the pre-composite for the intermediate region and diamond powder acts as an infiltration source during the sintering process for the sintering of the PCD layer.
  • At least some constituents in the pre-composite for the intermediate region melt during the HPHT sintering process.
  • the sintering time was 20-40 minutes, and in some examples was a number of hours.
  • the diamond composite structure forming the intermediate region contained about 60% by volume diamond and there was substantially no interbonding between the diamond grains in the diamond composite structure.
  • the matrix material of the intermediate region in this example was determined to include one or more of TiCN, AI2O3, and AI4C3
  • the cutter construction was recovered after sintering and fully processed to a diameter of around 16 mm and an overall height of around 13 mm with a PCD table thickness of about 1 3mm separated from the substrate by the intermediate region formed of a diamond composite having a thickness of between around 0.7mm to 0.85mm.
  • the intermediate region formed of the diamond composite extended to the peripheral side edge ofthe construction, the excess WC forming the substrate during sintering having been removed to expose the peripheral side edge of the PCD layer and the intermediate region.
  • the super hard construction with the intermediate region and substrate attached was subjected to a boiling HCI acid leaching treatment for a number of hours until all accessible residual catalysing material had been removed from the interstitial spaces between inter-bonded diamond grains.
  • the composite material of the intermediate region is more acid resistant than polycrystalline diamond material having a binder-catalyst phase comprising cobalt, and/or more acid resistant than cemented carbide material.
  • the acid resistance of the material of the intermediate region being more acid resistant than PCD containing interstitial cobalt and/or WC may be determined by whether or not it is more resistant to acid damage after 30 hours in a mixture of boiling HCI and water where the HCI forms 20% and the water the residual 80% of the acid leaching mixture, and confirming that the material of the intermediate region shows less than a 10% reduction in its starting weight.
  • the materials used to form the intermediate region(s) in the various examples were separately tested to confirm that the super hard grains in the material were non- intergrown (non-interbonded) and therefore were diamond composite materials in the examples and not considered to be polycrystalline diamond (PCD) material.
  • the tests performed included vertical boring mill tests with two leached conventional polycrystalline diamond cutter elements formed of diamond grains having an average grain size identical to the grain size in the respective diamond composite materials and which were sintered under pressures of around 5.5GPa.
  • the wear resistance of the diamond composite material was at least three times less (ie worse) than that of the conventional PCD which assisted in proving that the diamond composite materials forming the intermediate region were not intergrown and therefore were not considered to be polycrystalline diamond materials. This was also evident from SEM and X-ray images ofthe structures which showed the diamond grains coated with nano-sized cBN particles not to be inter- bonded (ie not inter-grown) and therefore not classed as PCD material.
  • the performance of the example cutter construction was significantly better than a conventional cutter formed of a PCD layer bonded to a WC substrate in which the PCD layer had the same average grain size as the PCD layer of the example and same PCD layer thickness that had not been subjected to an acid leaching treatment to remove all of the residual catalyst from the PCD region.
  • the composition and structure of the intermediate region provides a good support to the TS super hard structure, particularly as, for example, it is known that leaching conventional PCD typically reduces the strength ofthe PCD by up to around 30%.
  • the intermediate region may be shaped to suit the particular end application of the superhard construction, for example, to ensure that a large surface area of TS superhard material may be presented at the cutting edge so that as the wear scar progresses, the wear is contained in the TS region which is supported by a tough and strong supporting intermediate region.
  • a protrusion from the intermediate region may have a higher impact resistance compared to the superhard layer and thereby act to assist in arresting cracks to avoid spalling or catastrophic failure during use of the superhard construction.
  • the size and shape of the intermediate region and the TS super hard region may be tailored to the final application of the superhard material. It is believed possible to improve spalling resistance without significantly compromising the overall abrasion resistance of the material, which is desirable for PCD and PCBN cutting tools.
  • examples of, for example, a PCD material may be formed having a combination of high abrasion and fracture performance.
  • the superhard constructions may be finished by, for example, grinding, to provide a super hard element which is substantially cylindrical and having a substantially planar working surface, or a generally domed, pointed, rounded conical or frusto- conical working surface.
  • the super hard element may be suitable for use in, for example, a rotary shear (or drag) bit for boring into the earth, for a percussion drill bit or for a pick for mining or asphalt degradation.
  • each of the non-intergrown diamond grains in the third region have a coating comprising nano-sized cBN particles.to render the PCD thermally stable, the PCD structure with the intermediate region attached may be subjected to acid to leach out catalyst material from between the diamond grains, or to other methods of achieving this, such as electrochemical methods.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Organic Chemistry (AREA)
  • Ceramic Engineering (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Geology (AREA)
  • Mining & Mineral Resources (AREA)
  • Metallurgy (AREA)
  • Structural Engineering (AREA)
  • Geochemistry & Mineralogy (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Fluid Mechanics (AREA)
  • Environmental & Geological Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Composite Materials (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Earth Drilling (AREA)
  • Cutting Tools, Boring Holders, And Turrets (AREA)

Abstract

La présente invention concerne une construction polycristalline extra-dure qui comprend une première région comportant un corps de matériau extra-dur polycristallin thermiquement stable ayant une surface exposée formant une surface de travail, et un bord latéral périphérique. Le matériau extra-dur polycristallin comporte une pluralité de grains coalescents de matériau extra-dur, une deuxième région formant un substrat sur la première région, et une troisième région intercalée entre les première et deuxième régions. La troisième région s'étend sur une surface de la deuxième région le long d'une interface, la troisième région ayant un matériau composite ayant une première phase comprenant une pluralité de grains de diamant non coalescents, la majorité desdits grains de diamant ayant un revêtement comprenant des particules de cBN de taille nanométrique. L'invention concerne en outre un procédé de formation d'une telle construction.
PCT/EP2018/086593 2017-12-31 2018-12-21 Constructions extra-dures et leurs procédés de fabrication WO2019129711A1 (fr)

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WO2016135332A1 (fr) * 2015-02-28 2016-09-01 Element Six (Uk) Limited Constructions extra-dures & leurs procédés de production
WO2017009417A1 (fr) * 2015-07-15 2017-01-19 Element Six (Uk) Limited Constructions polycristallines extra-dures et leurs procédés de fabrication
US20170361424A1 (en) * 2014-12-31 2017-12-21 Element Six (Uk) Limited Superhard components and powder metallurgy methods of making the same

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CN103966533B (zh) * 2013-01-30 2016-12-28 中国科学院宁波材料技术与工程研究所 一种金刚石导热复合材料及其制备方法

Patent Citations (3)

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Publication number Priority date Publication date Assignee Title
US20170361424A1 (en) * 2014-12-31 2017-12-21 Element Six (Uk) Limited Superhard components and powder metallurgy methods of making the same
WO2016135332A1 (fr) * 2015-02-28 2016-09-01 Element Six (Uk) Limited Constructions extra-dures & leurs procédés de production
WO2017009417A1 (fr) * 2015-07-15 2017-01-19 Element Six (Uk) Limited Constructions polycristallines extra-dures et leurs procédés de fabrication

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GB201820954D0 (en) 2019-02-06
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GB2569892A (en) 2019-07-03
GB2569892B (en) 2021-07-14

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