EP0046209B1 - Outils et compositions ayant une structure macroscopique acier-carbure dur et leur procédé de fabrication - Google Patents

Outils et compositions ayant une structure macroscopique acier-carbure dur et leur procédé de fabrication Download PDF

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EP0046209B1
EP0046209B1 EP81105783A EP81105783A EP0046209B1 EP 0046209 B1 EP0046209 B1 EP 0046209B1 EP 81105783 A EP81105783 A EP 81105783A EP 81105783 A EP81105783 A EP 81105783A EP 0046209 B1 EP0046209 B1 EP 0046209B1
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Prior art keywords
carbide
steel
hard
cemented
iron
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German (de)
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EP0046209A1 (fr
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Nicholas Makrides
William Max Stoll
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Kennametal Inc
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Kennametal Inc
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    • 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
    • C22C29/10—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 titanium carbide
    • 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
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C1/00—Making non-ferrous alloys
    • C22C1/04—Making non-ferrous alloys by powder metallurgy
    • C22C1/05—Mixtures of metal powder with non-metallic powder
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C1/00—Making non-ferrous alloys
    • C22C1/04—Making non-ferrous alloys by powder metallurgy
    • C22C1/05—Mixtures of metal powder with non-metallic powder
    • C22C1/051—Making hard metals based on borides, carbides, nitrides, oxides or silicides; Preparation of the powder mixture used as the starting material therefor
    • 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
    • C22C29/067—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 comprising a particular metallic binder
    • 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
    • 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
    • B22F2999/00—Aspects linked to processes or compositions used in powder metallurgy

Definitions

  • cemented carbide alloys consisting of a finely- dispersed hard-carbide phase based on metals chosen from Groups IVB, VB and VIB of the Periodic table, cemented by cobalt or nickel or both.
  • cemented carbide alloys possess micro-structures characterized by hard carbide grains generally in the 1 to 15 micron range.
  • iron or steel as binder materials has proven difficult because the finely-divided state and high specific surface of the dispersed hard phases promote the formation of comparatively brittle binary interstitial alloys of tungsten and iron with carbon, thus reducing the free binder volume fraction and embrittling the sintered body, more or less, depending on the precision maintained in the formulation and sintering parameters and on the free carbon additions made to satisfy the affinity between iron and carbon.
  • iron forms a stable carbide, Fe 3 C, and has a greater tendency to form brittle binary carbides than cobalt or nickel binder materials.
  • Carbon transfer from the hard carbide phase or phases to iron is promoted by the presence of the liquid or plastic state of an iron or steel binder during liquid-state sintering, carried out at temperatures near to, at, or above the melting point of the binder.
  • useful wear parts have been made by casting a liquid steel or cast iron melt into a prepared bed of comparatively coarse particulate, e.g. 3.175 to 4.763 mm sintered, cemented carbide.
  • CH-A-215 453 discloses a composition of matter comprising at least 80% of a carbide material selected from the group consisting of tungsten carbide and mixtures of tungsten carbide with other carbides such as titanium carbide, tantalum carbide, niobium carbide or vanadium carbide, and 20% maximum of an auxiliary metal such as cobalt, nickel and/or iron.
  • a carbide material selected from the group consisting of tungsten carbide and mixtures of tungsten carbide with other carbides such as titanium carbide, tantalum carbide, niobium carbide or vanadium carbide, and 20% maximum of an auxiliary metal such as cobalt, nickel and/or iron.
  • cemented carbide tools consisting of a base of sintered alloy such as nickel-iron, iron-chromium-tungsten alloy or molybdenum alloy.
  • GB-A-530 639 teaches a process of producing tools having supporting bodies provided with insets of hard metal with the insets being molded from a powdered mixture of carbides, borides, nitrides, and the like of a metal of the tungsten group, and of a binding metal which preferably consists of the same metal of which the supporting body is made, namely iron, steel, and other metals of the iron group.
  • the present invention may be distinguished from the molten-steel casting method of Charles S. Baum, US-A-Nos. 4,024,902 and 4,140,170 and the molten-cast iron method of Sven Karl Gustav Ekemar in US-A-4,119,459 by two main factors: (1) a powder compact of steel or iron and graphite containing dispersed particulates or sintered, cemented carbide, or a number of pieces of dimensioned sintered cemented carbide, or primary, unmilled macrocrystalline carbide crystals is sintered at a temperature below the melting temperature of steel or cast iron, and (2) in place of the use of matrix-alloy melting temperatures to achieve alloy densification, high compaction unit pressures, both before and after sintering, are used, thereby avoiding degradation of the dispersed hard phase particle surfaces by decomposition, melting or carbon diffusion reactions.
  • Foundry methods also, lack tha well-known economic advantages inherent in powder metallurgy methods, notably, when a multiplicity of wear parts either small or of thin section are to be made. Also, because of the necessarily relatively high processing temperatures and liquidity, excessive amounts of unwanted binary carbides may form despite the use of comparatively coarse, low-surface area carbide particles.
  • This invention provides a solid-state sintered steel hard carbide composite wear resistant body comprising:
  • the said carbide material additionally has a metallic coating forming a tough and adherent bond between said carbide material and said matrix.
  • the method of the present invention for manufacturing the said composite wear resistant body involves blending and mixing sintered, cemented tungsten carbide particles or primarily unmilled macrocrystalline (i.e., greater than 37 pm) tungsten carbide crystals with a matrix of iron and graphite powders or steel powder, cold isostatically pressing the composite in a preform mold to a desired shape, then solid-state sintering at a comparatively low temperature, specifically, at a temperature below the melting temperature of the steel, preferably, between 1038°C and 1232°C, then hot isostatically solid-state pressing (HIP) the sintered body at a temperature well below the melting point of steel to achieve final densification.
  • a diffusion body is formed between the hard carbide particles and the surrounding steel powder, which holds the wear-resistant hard carbide particles in place.
  • the present invention is concerned with a tool made by the same method according to the invention comprising: a working end having a hard wear resistant cemented carbide insert; a body having steel; a bond region joining said insert to said body; characterized in that said bond region comprises an alloy having iron and cobalt and being essentially free of brittle double carbides of iron and tungsten.
  • this invention is concerned with the use of said method for forming said cemented carbide tool comprising embedding a predimensioned cobalt cemented carbide insert in a predetermined Icoation in a blend of steel forming powder; consolidating said powder around said insert to form a preform; and interdiffusing cobalt from said insert with iron from said consolidated steel forming powder adjacent the insert at a high temperature below the temperature at which the steel is at least partially liquid and, simultaneously at a high pressure, to form a metallurgical bond between said insert and said steel.
  • a critical factor of the present invention is high-pressure densification, both cold and hot, to avoid process temperatures which produce liquidity of the steel binder phase and, thus, promote the aforementioned undesirable reactions between the steel binder material and hard dispersed phase.
  • the technique is reinforced in this respect by the use of a hard dispersed particle or particles of low specific surface.
  • the method also provides a significant advance in production capability small size or of thin section or intricate design, as compared with methods as disclosed in United States patents hereinbefore enumerated in which molten steel or molten cast iron are poured into a mold preloaded with particles or cemented carbide.
  • both chemical control of and compositional flexibility of the matrix alloy are superior to molten-metal casting methods.
  • the avoidance of high processing temperatures required to melt and pour steel or cast iron provides better economy of molds, which may be reused, and matrix metals, which are not subject to pouring loss and recycle cost.
  • the method of the present invention is well suited for the formation of parts that must withstand highly abrasive wear forces as well as impact forces.
  • the process is ideally suited to form wear-resistant parts and cutting tools for equipment for agriculture, road and highway construction and maintenance, crushing, comminuting, excavation, and processing. Since the wear resistance of the products produced by this process is so high, so as to make them practically nonmachinable, they are also ideally suited for use as security plates in safes. This wear resistance in combination with the impact resistance of these compositions makes then also suitable for use in padlocks.
  • Prealloyed steel matrix powder or a mixture of iron powder and graphite powder, comprising 20 weight per cent (w/o) to 70 w/o of the final mixture is blended and mixed with 30 w/o to 80 w/o of hard carbide particles of W, Ti, Ta, Nb, or Zr, V, Hf, Mo, B, Si, Cr or a mixture of these, either as sintered cemented carbide particles or as primary, uncemented, unsintered, unmilled carbide crystals. About 3 percent of naphtha or other liquid hydrocarbon is added to the powder blend during mixing to prevent segregation of higher density carbide particles during mixing and mold filling, specifically when the dispersed hard phase is composed of hard carbide particles coarser than about 250 microns.
  • paraffin wax or a solid lubricant such as zinc stearate may be used, because the possibility of component particle segregation during mixing is then diminished.
  • the matrix powder containing the dispersed hard carbide phase is packed in a preform mold made of polyurethane or other elastomeric plastic.
  • Steel powders of different chemical compositions such as carbon, alloy or stainless steel powders
  • elemental powders such as iron, copper or nickel
  • the packed mold with a suitable fitted cover is then sealed and placed in a rubber bag or balloon which is then evacuated, sealed and isostatically pressed, preferably at about 2,413.25.10 5 Pa, but not less than 689.5,10 5 Pa.
  • the compacted powder preform is then removed from the mold and heated in vacuum or in a protective or reducing gas atmosphere, e.g., hydrogen, to a temperature below the melting temperature of the steel matrix, preferably between 1038°C and 1149°C, for between 20 and 90 minutes.
  • a protective or reducing gas atmosphere e.g., hydrogen
  • An alternative preforming method consists of packing the composite mixture containing preferably liquid hydrocarbon, e.g. naphtha, preferably 7 w/o and methyl cellulose, preferably 0.5 w/o, as pressing lubricant and green-state binder, respectively, in a steel preform mold.
  • the green preform is then air dried at room temperature, in the mold, then removed from the mold and placed in a rubber bag which is then evacuated and sealed, ready for cold isostatic compaction as hereinbefore described.
  • Hot isostatic pressing for the purpose of this invention is applied in an inert atmosphere, preferably at 871°C to 1260°C or at any temperature below the melting temperature of the steel for from 20 to 90 minutes at a minimum pressure of 689.5-10 5 Pa but, preferably at a pressure of about 1,034.25-10 5 Pa for 60 minutes.
  • an alloy layer is formed at the interfaces of cemented carbide particles and steel matrix.
  • This interfacial alloy bond which first forms during sintering and is later enhanced during hot isostatic pressing, consists of a thin border area between, for example, a 0.75 per cent carbon steel matrix and dispersed cobalt-cemented carbide particles in a 3.175 to 4.763 mm size range.
  • the bond is typically less than 40 microns thick, and no greater than 50 microns thick.
  • the interfacial bonding alloy under these conditions is composed of, principally, cobalt and iron. Bond formation becomes important especially when the hard dispersed phase is of comparatively coarse particles, because these are apt to pull out if not securely anchored in the matrix alloy.
  • Cemented tungsten carbide particle sizes comprising the dispersed hard phase are selected from within the general size range of 8 mm to 0.149 mm (2.5 mesh to 100 mesh in the U.S. sieve series), preferred size ranges being of from 0.84 to 1.53 mm (+20 to -12 mesh), from 1.53 to 3.36 mm (+12 to -6 mesh), and from 3.36 to 4.76 mm (+6 to -4 mesh). Specific selected size ranges may be prepared by known methods of crushing and sizing sintered, cemented carbide tool components, and which alloys are more commonly of a cobalt or nickel-cemented tungsten carbide (WC) base, sometimes containing also TiC, TaC or NbC or combinations of these hard carbides.
  • WC nickel-cemented tungsten carbide
  • An additional useful aspect in the process of the present invention is to apply a coating of an alloy or metal, preferably Corson bronze or nickel, on the surfaces of a dimensioned sintered cemented tungsten carbide insert of selected shape and size, or a number of such inserts, which are then embedded in a steel or iron-graphite matrix powder at selected locations within a preform mold before the filled mold is isostatically compacted.
  • the corson bronze coating used may be either of the two nominal compositions shown in Table I.
  • a cemented carbide body or a number of them, of specific shape and size may replace a dispersed hard carbide phase of particulate nature, and thereby form a wear-resistant body or a tool for cutting or drilling metal or rock.
  • the comparatively low processing temperatures employed in the process of this invention may, in cases in which steel matrix powder compositions are used which do not bond well to particles of a dispersed hard carbide phase, result in inadequate bond strength at the matrix-carbide particle interface.
  • alloy steel powders which are known to be less sinterable at the comparatively low solid-state sintering temperatures described in the process of this invention
  • Nickel coatings thus applied to the hard carbide dispersed fraction, prior to blending have been found to improve carbide particle bonding strength.
  • Such precoating of the hard carbide particles would also be beneficial when stainless steel powders are being used.
  • a further and useful part of the foregoing method is the incorporation of a dispersed hard carbide phase in a steel or iron-graphite powder compact consisting of unmilled macrocrystalline carbide crystals in size range fractions between 0.037 and 0.250 mm (betweeen 400 and 60 mesh) and in preferred size ranges of e.g. from 0.149 to 0.250 mm (+100 to -60 mesh), from 0.074 to 0.177 mm (+200 to -80 mesh), or from 0.044 to 0.099 mm (+325 to -150 mesh), instead of and in place of particles of cemented carbide.
  • the method of the present invention for formulating and forming macrostructred cemented carbide compositions is exactly as heretofore described.
  • the relatively low processing temperature practiced results in a macrostructure essentially free of brittle double carbides of iron and tungsten (eta phase) and gross porosity.
  • eta phase brittle double carbides of iron and tungsten
  • the tendency for liquid-phase sintered, microstructured, cemented tungten carbide alloys employing a steel binder, for example, in place of the usual cobalt binder, to develop brittle eta-type phases is well known. It is believed that the avoidance of liquid phase sintering and consequently the avoidance of carbon- transfer that such practice encourages, as well as the uniquely low specific surface of the unmilled macrocrystalline carbide particles comprising the dispersed hard phase are essential for the successful formation of the two-phase, steel-carbide macrostructures produced by this method.
  • liquid phase sintering as referred to herein means sintering at a temperature at which the steel binder is at least partially liquid.
  • the prohibition of liquid phase sintering in this invention therefore, does not apply to any lower melting point metals or alloys (e.g., copper or corson bronze) which may be added as a powder or coating to promote bonding or densification, and may intentionally become liquid during sintering or hot isostatic pressing.
  • unmilled macrocrystalline hard carbide crystals as a dispersed hard phase is a preferred embodiment of the method of this invention, as an efficient means of maintaining a hard phase possessing low specific surface. It is recognized, however, that essentially binderless, hard aggregates of finer or milled hard carbides may be so used.
  • An important aspect of the aforementioned macrostructured bodies is the avoidance of ball milling or other comminution of the matrix-carbide powder mixtures, or of either of these two materials separately, prior to cold isostatic compaction, sintering and HIP.
  • the former practice widely considered essential to sound commercial cemented carbide structures, leads to enhanced reaction between carbides and iron-base matrix powders with resultant formation of brittle double carbides. Avoidance of powder milling also reduces cost.
  • the method of the invention may employ any of the macrocrystalline carbides, or combinations or solid solutions of them, specifically WC, TiC, TaC or NbC, all exhibiting the low specific surface and angular, blocky shapes typifying these coarsely-crystalline mono and binary carbides.
  • primary macrocrystalline carbide materials may be finely milled, together with cobalt or nickel, to form cemented carbide micro-structures by liquid-phase sintering in the temperature range 1316°C to 1538°C, in which the resultant dispersed hard carbide phases are typically between one micron and about ten microns.
  • the method of the invention in contast, results in dispersed, single macrocrystalline carbide grains in size ranges selected from within the much coarser extremes of 250 microns to about 40 microns.
  • Wear resistant cutting tips were fabricated for rotary sugar cane shredding machines.
  • a uniformly blended mixture composed of approximately 55 w/o 3.175 to 4.763 mm cobalt cemented tungsten carbide granules, approximately 44.67 w/o to less than 0.149 mm atomized iron powder and 0.33 w/o of smaller than 0.044 mm graphite powder was prepared.
  • 5 w/o of naphtha was added to minimize segregation of the higher-density cemented carbide particles.
  • the dample mixture was manually compacted into an elastomeric polyurethane mold cavity of the desired tool shape, dimensioned to allow for cold isostatic powder compaction plus one per cent sintering shrinkage.
  • the compacted preform was removed from the mold and vacuum sintered at 1093°C for 60 minutes, following which the sintered body was isostatically pressed at 1232°C for 60 minutes at 1,034.25 ⁇ 10° Pa under helium.
  • Metallographic examination disclosed a matrix structure composed of mostly pearlite and a little ferrite typical of conventional slow-cooled 0.75 per cent carbon steel of low porosity.
  • the cemented carbide-matrix interfaces were occupied by bands of a width of about 5 microns of an alloy believed to be composed of iron and cobalt, principally.
  • the cemented carbide dispersed particles appeared unimpaired by thermal cracking and no evidence of dissolution, melting or decomposition of the dispersed carbide phase existed at or near the interfacial boundaries, such boundaries being sharp except for the aforementioned iron-cobalt alloy diffusion zone. No potentially harmful concentrations of eta phase were observed.
  • Test bodies were manually bent over a mandrel by hammering at room temperature and found to have a high resistance to impact loading and to be essentially free of brittle fracture.
  • Figure 1 is a photomicrograph of a typical area in a composite produced according to Example 1, except that sintering was done at 1149°C.
  • a cobalt cemented tungsten carbide granule 40 is shown metallurgically bonded to a plain carbon steel having a mostly pearlitic structure 50 by a diffusion zone 45 containing iron and cobalt.
  • the diffusion zone 45 is approximately 3 microns thick.
  • a wear-resistant, 12.9 cm 2 by 0.95 cm thick plate was fabricated consisting of 60 w/o of unmilled macrocrystalline WC having a particle size of from 0.149 to 0.250 mm (+100 to -60 mesh) and being cemented by 40 w/o of 0.75 per cent C steel containing 2 w/o Cu.
  • a uniformly dry blended mixture of macrocrystalline WC crystals having a particle size of from 0.149 to 0.250 mm (+100 to -60 mesh), graphite powder having a particle size of less than 0.044 mm (-325 mesh), iron powder of less than 0.149 mm (-100 mesh), and copper powder of less than 0.044 mm (-325 mesh) were dry blended, unmilled, to a uniform mixture, then dampened by blending with liquid naphtha and methyl cellulose equal, respectively, to 7 per cent and 0.5 w/o of the dry mixture, and then packed into a steel preform mold to a firm, green, plate shape of dimensions equal to approximately 102 per cent of the desired final dimension.
  • Example No. 1 Metallographic examination revealed a macrostructure of macrocrystalline WC evenly dispersed throughout a steel matrix. A 5 micron thick bond layer of unknown composition was observed at WC-steel interfaces.
  • a composite 38.1 mm cubic wear-resistant body of steel enclosing a dimensioned plate of sintered, cemented 5 w/o cobalt-tungsten carbide was fabricated, purposefully embedding the dimensioned plate of sintered, cemented carbide in the green powder prior to iso-compaction so that its outer surface was flush with the outer surface of the steel cube.
  • a dry unmilled blend comprised of 97.25 w/o to less than 0.149 mm (-100 mesh) atomized iron powder, 2 w/o less than 0.044 mm (-325 mesh) Cu powder and 0.75 w/o graphite was made, then blended with naphtha and methyl cellulose equal to, respectively, 5 w/o and 0.3 w/o of the dry blend. This was then packed into an elastomeric mold following which a 25.4 mm square by 6.35 mm thick plate of sintered cemented carbide was pressed down into the iron powder mix so that the outer surfaces were congruent.
  • Example No. 1 Metallographic examination revealed that the prepositioned sintered carbide plate was bonded by a 5 micron interfacial bond phase to the steel matrix surrounding it on three sides and that the entire structure appeared sound and free of cracks.
  • Figure 2 presents a description of a wear plate 20 manufactured in the manner described in this example, except that three rather one cemented carbide inserts 30 are embedded in the plate 20 such that a surface 45 of each insert 30 is substantially flush with the working end 40 of the tool 20. It will be noted that the interfacial bond 35 is substantially uniform and continuous and forms a tough and adherent bond between the cemented carbide and the consolidated carbon steel and copper matrix 25.
  • stainless steel or alloy steel powders may be advantageously substituted for the iron, carbon and copper powders utilized in this example.
  • Figure 3 provides a cross sectional view of another embodiment of a tool according to the present invention.
  • This tool 1 can be manufactured substantially as described in Example 3, except that the cemented carbide insert 5 is allowed to have its working end 2 extend outward and beyond the steel body 10 of tool 1.
  • the insert 5 bonded to the steel body 10 by a diffusion zone 15 which was formed by the interdiffusion of cobalt from the insert 5 and iron from the steel body 10 during high temperature and high pressure sintering operations.

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Claims (18)

1. Corps composite résistant à l'usure, de carbure dur et d'acier, fritté à l'état solide, comprenant 30 à 80% en poids d'un matériau à base de carbure ayant une dimension supérieure à 37 pm, le matériau à base de carbure étant choisi dans le groupe des carbures durs comprenant le carbure de tungstène, le carbure de titane, le carbure de tantale, le carbure de niobium, le carbure de zirconium, le carbure de vanadium, le carbure de hafnium, le carbure de molybdène, le carbure de chrome, le carbure de bore, le carbure de silicium, leur mélanges, leurs solutions solides et les éléments composites frittés formés avec eux, 20 à 70% en poids d'un matériau formant un liant choisi dans le group qui comprend l'acier, l'acier et le fer, l'acier et le cuivre, et l'acier et le nickel, le matériau à base de carbure étant enrobé dans le liant et lié à celui-ci, et une interface formée entre le matériau à base de carbure et le liant et ayant une épaisseur qui ne dépasse pas 5 microns, l'interface étant pratiquement dépourvue de carbures doubles fragiles.
2. Corps selon la revendication 1, caractérisé en outre en ce que l'interface a une épaisseur comprise entre 0 et 40 pm.
3. Corps selon la revendication 1, dans lequel le matériau à base de carbure est un élément composite fritté ayant un liant de cobalt, et caractérisé en outre en ce que l'interface a du fer et du cobalt et une épaisseur de 0 à 40 pm.
4. Corps selon la revendication 3, caractérisé en outre en ce que l'élément composite fritté contient du carbure de tungstène.
5. Corps selon la revendication 1, caractérisé en outre en ce que le carbure dur est le carbure de tungstène.
6. Corps selon la revendication 1, caractérisé en outre en ce que le corps est ductile à température ambiante.
7. Corps selon l'une quelconque des revendications 1, 3 et 5, caractérisé en outre en ce que l'acier est un acier allié.
8. Corps selon l'une quelconque des revendications 1, 3 et 5, caractérisé en ce que l'acier est un acier inoxydable.
9. Corps composite résistant à l'usure à base de carbure dur et d'acier, fritté à l'état solide, contenant 30 à 80% en poids d'un matériau à base de carbure ayant une dimension supérieure à 37 pm et ayant un revêtement métallique, le matériau à base de carbure étant choisi dans le groupe des carbures durs formés du carbure de tungstène, du carbure de titane, du carbure de tantale, du carbure de niobium, du carbure de zirconium, du carbure de vanadium, du carbure de hafnium, du carbure de molybdène, du carbure de chrome, du carbure de bore, du carbure de silicium, de leurs mélanges, de leurs solutions solides et des éléments composites frittés formés à partir d'eux, 20 à 70% en poids d'un matériau formant liant choisi dans le groupe quie comprend l'acier, l'acier et le fer, l'acier et le cuivre, et l'acier et le nickel, le revêtement métallique formant une liaison tenace et adhérente entre le matériau à base de carbure et le liant.
10. Corps selon la revendication 9, caractérisé en outre en ce que l'acier est choisi dans le groupe formé des aciers alliés est des aciers inoxydables.
11. Corps selon l'une quelconque des revendications 1 à 10, contenant 30 à 80% en poids d'un matériau à base de carbure ayant une dimension supérieure à 37 pm, le matériau à base de carbure étant choisi dans le group des carbures durs comprenant le carbure de tungstène, le carbure de titane, le carbure de tantale, le carbure de niobium, le carbure de zirconium, le carbure de vanadium, le carbure de hafnium, le carbure de molybdène, le carbure de chrome, le carbure de bore, le carbure de silicium, leurs mélanges, leurs solutions solides et les éléments composites frittés les contenant, 20 à 70% en poids d'un matériau formant un liant choisi dans le groupe constitué par l'acier, l'acier et le fer, l'acier et le cuivre, et l'acier et le nickel, caractérisé en ce que le matériau à base de carbure est enrobé dans le liant et lié à celui-ci par les techniques de la métallurgie des poudres comprenant une compression et une liaison par diffusion à l'état solide.
12. Procédé de fabrication des corps composites résistant à l'usure à base de carbure dur et d'acier selon l'une quelconque des revendications 1 à 8 et 11, comprenant 1 mélange de 20 à 70% en poids de poudres destinées à former de l'acier avec 30 à 80% en poids de particules de carbure dur ayant une dimension particulaire comprise entre 8 mm et 37 pm afin qu'un mélange soit formé, les poudres destinées à former de l'acier étant choisies dans le groupe comprenant le fer et le graphite, les aciers alliés et les aciers inoxydables, les particules de carbure dur étant choisies dans le groupe des carbures durs comprenant le carbure de tungstène, le carbure de titane, le carbure de tantale, le carbure de niobium, le carbure de zirconium, le carbure de vanadium, le carbure de hafnium, le carbure de molybdène, le carbure de chrome, le carbure de bore, le carbure de silicium, leurs mélanges, leurs solutions solides et les éléments composites frittés les contenant, la compression à froid du mélange sous forme d'une ébauche comprimée, et la densification à l'état solide de l'ébauche comprimée par une opération de frittage et de liaison par diffusion à température élevée et à pression élevée, comprenant un frittage à l'état solide de l'ébauche comprimée à une température supérieure à 1038°C et inférieure à la température de solidus de l'acier afin que la porosité inter- connectée dans l'ébauche soit minimale, puis la compression isostatique à chaud à l'état solide de l'ébauche à une pression supérieure à 689,5.105 Pa et à une température comprise entre 871°C et la température de fusion de l'acier.
13. Procédé selon la revendication 12, destiné à la fabrication de corps composites résistants à l'usure à base de carbure dur et d'acier selon l'une quelconque des revendications 9 à 11, caractérisé en outre par le revêtement des particules de carbure dur par un revêtement métallique avant le mélange avec les poudres destinées à former de t'acier.
14. Outil fabriqué par le procède de la revendication 12 ou de la revendication 13, comprenant une extrémité de travail ayant un élément rapporté de carbure dur fritté résistant à l'usure, un corps contenant de l'acier, une région de liaison reliant l'élément au corps, caractérisé en ce que la région de liaison contient un alliage ayant du fer et du cobalt et étant pratiquement dépourvu de carbures doubles fragiles de fer et de tungstène.
15. Outil fabriqué par le procédé de la revendication 12 ou de la revendication 13, comprenant une extrémité de travail ayant un élément rapporté de carbure fritté par du cobalt, dur et résistant à l'usure, un corps contenant de l'acier, l'élément rapporté étant lié par les techniques de la métallurgie des poudres au corps par une zone de diffusion formée pendant un frittage à l'état solide à température élevée, mais inférieure à la température de fusion de l'acier, la zone diffusée ayant du fer et du cobalt et étant pratiquement dépourvue de carbure double fragile de fer et de tungstène.
16. Outil selon la revendication 12 ou la revendication 13, comprenant une extrémité de travail ayant un élément rapporté de carbure fritté dur et résistant à l'usure, l'élément rapporté contenant 30 à 80% en poids d'un matériau à base de carbure choisi dans le groupe des carbures durs qui comprend le carbure de tungstène, le carbure de titane, le carbure de tantale, le carbure de niobium, le carbure de zirconium, le carbure de vanadium, le carbure de hafnium, le carbure de molybdène, le carbure de chrome, le carbure de bore, le carbure de silicium, leurs mélanges, leurs solutions solides et les éléments composites frittés les contenant, et 20 à 70% en poids d'un matériau formant liant choisi dans le groupe qui comprend l'acier, l'acier et le fer, l'acier et le cuivre, et l'acier et le nickel, un corps contenant de l'acier, l'élément rapporté étant lié par les techniques de la métallurgie des poudres au corps par une zone de diffusion formée pendant le frittage à l'état solide, à température élevée mais inférieure à la température à laquelle le liant d'acier est au moins partiellement liquide, la zone de diffusion étant pratiquement dépourvue de carbures doubles fragiles de fer et de tungstène.
17. Application du procédé selon la revendication 12 ou la revendication 13, destiné à la formation d'un outil de carbure fritté selon la revendication 14 ou la revendication 15, caractérisé par l'enrobage d'un élément rapporté lié par du cobalt, ayant des dimensions prédéterminées, à un emplacement prédéterminé dans un mélange d'une poudre dèstinée à former de l'acier, la consolidation de la poudre autour de l'élément rapporté afin qu'une ébauche soit formée, et la diffusion mutuelle du cobalt de l'ébauche et du fer de la poudre consolidée des éléments destinés à former du fer, à proximité de l'élément rapporté, à une température élevée inférieure à la température à laquelle l'acier est au moins partiellement liquide, et, simultanément, la formation d'une liaison métallurgique entre l'élément rapporté et t'acier, à une pression élevée.
18. Application du procédé selon la revendication 12 ou la revendication 13, destiné à former l'outil de carbure fritté selon la revendication 16, comprenant l'enrobage d'un élément rapporté de carbure fritté ayant des dimensions prédéterminées à un emplacement prédéterminé dans un mélange d'une poudre destinée à former de l'acier, l'élément rapporté de carbure fritté ayant des dimensions prédéterminées contenant 30 à 80% en poids d'un matériau à base de carbure choisi dans le groupe des carbures durs qui comprend le carbure de tungstène, le carbure de titane, le carbure de tantale, le carbure de niobium, le carbure de zirconium, le carbure de vanadium, le carbure de hafnium, le carbure de molybdène, le carbure de chrome, le carbure de bore, le carbure de silicium, leurs mélanges, leurs solutions solides et les éléments composites frittés les contenant, et 20 à 70% en poids d'un matériau formant liant choisi dans le groupe qui comprend l'acier, l'acier et le fer, l'acier et le cuivre, et l'acier et le nickel, la consolidation de la poudre destinée à former de l'acier autour de l'élément rapporté ayant les dimensions prédéterminées afin qu'une ébauche soit formée, le frittage à l'état solide de l'ébauche, à une température comprise entre 1038 et 1232°C et simultanément à une pression supérieure à 689,5,105 Pa afin qu'une liaison métallurgique soit formée entre l'élément rapporté et l'acier.
EP81105783A 1980-08-18 1981-07-22 Outils et compositions ayant une structure macroscopique acier-carbure dur et leur procédé de fabrication Expired EP0046209B1 (fr)

Priority Applications (1)

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AT81105783T ATE22022T1 (de) 1980-08-18 1981-07-22 Grobstrukturierte werkzeuge, bzw. werkstoffe, aus stahl-hartkarbiden und herstellungsverfahren.

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US17880580A 1980-08-18 1980-08-18
US178805 1980-08-18
US25545381A 1981-04-20 1981-04-20
US255453 1981-04-20

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EP0046209B1 true EP0046209B1 (fr) 1986-09-10

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EP (1) EP0046209B1 (fr)
KR (1) KR850001553B1 (fr)
AU (1) AU553481B2 (fr)
CA (1) CA1188136A (fr)
DE (1) DE3175299D1 (fr)
DK (1) DK158957C (fr)
ES (2) ES504800A0 (fr)
FI (1) FI72753C (fr)
IE (1) IE52094B1 (fr)
IL (1) IL63549A (fr)
MX (1) MX157680A (fr)
NO (1) NO159773C (fr)
NZ (1) NZ197962A (fr)
PT (1) PT73531B (fr)

Cited By (3)

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Publication number Priority date Publication date Assignee Title
US7556668B2 (en) 2001-12-05 2009-07-07 Baker Hughes Incorporated Consolidated hard materials, methods of manufacture, and applications
WO2019109098A1 (fr) * 2017-12-01 2019-06-06 Milwaukee Electric Tool Corporation Outil rapporté résistant à l'usure
USD955843S1 (en) 2018-08-10 2022-06-28 Milwaukee Electric Tool Corporation Driver bit

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SE453649B (sv) * 1984-11-09 1988-02-22 Santrade Ltd Verktyg i form av en kompoundkropp bestaende av en kerna och ett holje
DK165775C (da) * 1985-07-18 1993-06-14 Teknologisk Inst Fremgangsmaade til fremstilling af en sliddel til et jordbearbejdningsredskab
SE462182B (sv) * 1986-09-01 1990-05-14 Sandvik Ab Foerfarande foer framstaellning av en skyddsplatta i kompoundutfoerande saasom splitterskydd, kompoundpansar o d
DE4321143A1 (de) * 1993-06-25 1995-01-05 Saar Hartmetall & Werkzeuge Verbundkörper, bestehend aus Werkstoffen unterschiedlicher thermischer und mechanischer Eigenschaften
DE4340652C2 (de) * 1993-11-30 2003-10-16 Widia Gmbh Verbundwerkstoff und Verfahren zu seiner Herstellung
DE19855422A1 (de) 1998-12-01 2000-06-08 Basf Ag Hartstoff-Sinterformteil mit einem nickel- und kobaltfreien, stickstoffhaltigen Stahl als Binder der Hartstoffphase
DE19912721C1 (de) * 1999-03-20 2000-08-10 Simon Karl Gmbh & Co Kg Verfahren zum Herstellen einer Fräslamelle und nach dem Verfahren hergestellte Fräslamelle
US6854527B2 (en) 2002-04-08 2005-02-15 Kennametal Inc. Fracture resistant carbide snowplow and grader blades
CN113232380B (zh) * 2021-04-30 2023-03-28 咸阳职业技术学院 一种高强高韧层状互通结构钢结硬质合金及其制备方法

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GB530639A (en) * 1938-06-16 1940-12-17 Meutsch Voigtlaender & Co Process for the production of articles provided with coatings or insets of hard metal
CH215453A (de) * 1939-07-24 1941-06-30 Krupp Ag Aus einem Hartmetallkörper und einer Unterlage bestehender, als Arbeitsgerät oder Werkzeug verwendbarer Gegenstand.
SE333437B (fr) * 1969-03-03 1971-03-15 Asea Ab
DE2722271C3 (de) * 1977-05-17 1979-12-06 Thyssen Edelstahlwerke Ag, 4000 Duesseldorf Verfahren zur Herstellung von Werkzeugen durch Verbundsinterung
GB2007720B (en) * 1977-09-27 1982-08-18 Nippon Tungsten Cemented carbide layer
DE2916709A1 (de) * 1979-04-25 1980-10-30 Krebsoege Gmbh Sintermetall Werkzeuge mit schneiden aus harten stoffen

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7556668B2 (en) 2001-12-05 2009-07-07 Baker Hughes Incorporated Consolidated hard materials, methods of manufacture, and applications
US7691173B2 (en) 2001-12-05 2010-04-06 Baker Hughes Incorporated Consolidated hard materials, earth-boring rotary drill bits including such hard materials, and methods of forming such hard materials
US7829013B2 (en) 2001-12-05 2010-11-09 Baker Hughes Incorporated Components of earth-boring tools including sintered composite materials and methods of forming such components
US9109413B2 (en) 2001-12-05 2015-08-18 Baker Hughes Incorporated Methods of forming components and portions of earth-boring tools including sintered composite materials
WO2019109098A1 (fr) * 2017-12-01 2019-06-06 Milwaukee Electric Tool Corporation Outil rapporté résistant à l'usure
US11958168B2 (en) 2017-12-01 2024-04-16 Milwaukee Electric Tool Corporation Wear resistant tool bit
USD955843S1 (en) 2018-08-10 2022-06-28 Milwaukee Electric Tool Corporation Driver bit

Also Published As

Publication number Publication date
IL63549A (en) 1983-12-30
DE3175299D1 (en) 1986-10-16
ES8301433A1 (es) 1982-12-01
KR830006460A (ko) 1983-09-24
NZ197962A (en) 1985-05-31
KR850001553B1 (ko) 1985-10-17
DK158957C (da) 1991-01-21
AU7368081A (en) 1982-02-25
IE811872L (en) 1982-02-18
FI72753C (fi) 1987-07-10
ES504800A0 (es) 1982-12-01
NO812781L (no) 1982-02-19
DK158957B (da) 1990-08-06
ES514551A0 (es) 1983-10-16
NO159773B (no) 1988-10-31
MX157680A (es) 1988-12-09
DK364581A (da) 1982-02-19
EP0046209A1 (fr) 1982-02-24
AU553481B2 (en) 1986-07-17
IE52094B1 (en) 1987-06-10
FI812533L (fi) 1982-02-19
NO159773C (no) 1989-02-08
CA1188136A (fr) 1985-06-04
IL63549A0 (en) 1981-11-30
PT73531B (en) 1982-11-03
FI72753B (fi) 1987-03-31
ES8400271A1 (es) 1983-10-16
PT73531A (en) 1981-09-01

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