US3837848A - Method of making tools by impregnating a steel skeleton with a carbide, nitride or oxide precursor - Google Patents

Method of making tools by impregnating a steel skeleton with a carbide, nitride or oxide precursor Download PDF

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Publication number
US3837848A
US3837848A US00156029A US15602971A US3837848A US 3837848 A US3837848 A US 3837848A US 00156029 A US00156029 A US 00156029A US 15602971 A US15602971 A US 15602971A US 3837848 A US3837848 A US 3837848A
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Prior art keywords
percent
skeleton
pores
alloys
steel
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Expired - Lifetime
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US00156029A
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English (en)
Inventor
O Wessel
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Vodafone GmbH
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Mannesmann AG
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Priority claimed from DE19702032814 external-priority patent/DE2032814C/de
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Classifications

    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C19/00—Alloys based on nickel or cobalt
    • C22C19/07—Alloys based on nickel or cobalt based on cobalt
    • 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
    • B22F3/26—Impregnating
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C19/00—Alloys based on nickel or cobalt
    • C22C19/03—Alloys based on nickel or cobalt based on nickel
    • C22C19/05—Alloys based on nickel or cobalt based on nickel with chromium
    • C22C19/051—Alloys based on nickel or cobalt based on nickel with chromium and Mo or W
    • C22C19/055—Alloys based on nickel or cobalt based on nickel with chromium and Mo or W with the maximum Cr content being at least 20% but less than 30%
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C33/00—Making ferrous alloys
    • C22C33/02—Making ferrous alloys by powder metallurgy
    • C22C33/0257—Making ferrous alloys by powder metallurgy characterised by the range of the alloying elements
    • C22C33/0278—Making ferrous alloys by powder metallurgy characterised by the range of the alloying elements with at least one alloying element having a minimum content above 5%
    • C22C33/0285—Making ferrous alloys by powder metallurgy characterised by the range of the alloying elements with at least one alloying element having a minimum content above 5% with Cr, Co, or Ni having a minimum content higher than 5%
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/12—All metal or with adjacent metals
    • Y10T428/12014—All metal or with adjacent metals having metal particles
    • Y10T428/1216—Continuous interengaged phases of plural metals, or oriented fiber containing

Definitions

  • Another known method for making form parts of high hot strength or high temperature resistance and high hot hardness uses metal powder as raw material and frequently high melting oxides are added. The powder or mixture of powders is then compressed into porous blocks or billets, which are subsequently sintered to obtain high density. Sintering is to occur at high temperatures. Alternatively, hot pressing or hot extrusion is used for forming and condensing the parts to be made. In either case, it is deemed desirable to obtain a product having a high density.
  • the non-metallic parts, and preferably also the metal powder should be very fine in order to obtain a finally dispersed and essentially uniform distribution of the inclusion. As with present day knowledge, this is believed to result in parts of high strength.
  • the present invention is based on development and investigations that have been conducted independently from the foregoing and were particularly directed to the making of tools and dies to be used for hot working. It is important that the material worked with is considerably cheaper than the known alloys on nickel and cobalt basis. These developments have led to the result that, for example, a porous die or mold for extrusion, e.g., of steel pipes, and having a nitrogen content of about 1 percent could be made from chromium steel powder, having a longer service life than known dies and molds. Moreover, the product (e.g., pipe) had a better surface texture when such particular die was used.
  • the known materials do not have that property or only to a very unsatisfactory degree.
  • tool steel and martensitic aging steel as used to an increasing extent are very hard at temperatures up to about 550 C, but their strength decreases rapidly above that temperature. Above 550 C one uses exclusively the usually austenitic alloys having nickel or cobalt basis as was mentioned above but it was also stated above, that these alloys do not have the sufficient strength at lower temperature, and that was found to be detrimental for overall wear and life.
  • tools or dies to be used for hot forming of metal such as a press or rolling mandrel or a die of an extrusion molding machine or the like in the following manner.
  • the tool or die is made as a skeleton with a penetrating and all-pervading network of pores but at a total volume of pores less than 50 percent, preferably about 20 to 30 percent.
  • Metal to be used here is to have high hot strength and high temperature resistance.
  • the pores are to be filled with a non-metallic, an-organic material as completely as possible, and having significant hardness particularly below 650 C, so as to render the tool practically undeformable.
  • the mechanical properties are determined in the lower temperature range predominantly by the non-metallic component, while for temperatures above 650 C, the metal component of the skeleton determines predominantly these properties.
  • the particular tool or die, made in that manner, particularly with a total pore volume of less than 50 percent, has these pores filled with nonmetallic material either completely or only in zones of the tool engaging later the material to be worked; these zones may have a depth of about 5 to 10 mm, as filled with the non-metallic inclusion, while the remainder (interior) of the tool, has a relative density of percent and above.
  • the raw material, from which to make the tools or dies may be comprised of small particles of any form, such as flakes, shavings, powder, fibers, cuttings or the like. These particles are compressed and sintered, and the resulting porous part has the shape of the tool or die to be made.
  • a metallic body is produced penetrated by a continuous, allpervating network of pores, and that is actually the basis for defining the body as a skeleton. It is this a random type frame and support microstructure made of material of high temperature resistance.
  • a heat resisting steel alloy that could be used in accordance with the invention has composition shown in the following table.
  • Example Carbon max. 0.5 0.05 Silicon 0.2 2.0 l4 Manganese 0.3 l5 0.6 Chromium l 25 13 Nickel 4 2O l3 Tungsten up to l0 l4 Vanadium up to 2 l lron remainder remainder.
  • the following elements could be added to further increase hot strength:
  • Example Carbon max 0.5 0.02 Silicon 0.2 2.0 0.7 Manganese 0.3 l5 [.3 Chromium l0 25 25 Nickel 4 20 13.5 Tungsten up to 3.3 Vanadium up to Nitrogen 0.2 3.0 1.62 Iron remainder remainder A heat resisting nickel alloy may, for example, be made in accordance with Table C.
  • At least 57 A heat resisting cobalt alloy may be made in accordance with Table D.
  • the metal particles are poured into a mold and condensed subsequently. It is usually of advantage to sinter the pressed form so that the metal parts engage more intimately so as to establish an integral body.
  • the porous skeleton may be particularly treated in order to increase the hot strength and heat resistance; for example, there may be provided carbonization, nitrating or cold working.
  • the relative density of the skeleton is variable over a large range and may actually range from about 4 percent, if shavings are used, up to 90 percent for very fine powder or the like. Preferably, the relative density ranges from 60 to percent.
  • the metallic skeleton body has in each of these cases a network of pores which are more or less interconnected and penetrate the body throughout. They are now to be filled so that, in effect, a second network be produced, which, in turn, is penetrated by the metallic skeleton. This second and, in fact, coherent network of filler material is produced by infiltration, impregnating or the like. This may be combined with an annealing process, for example, upon sintering the metal skeleton body, but impregnation could be carried out in a separate process.
  • the melted, i.e., liquified, material that is to penetrate the pores of the skeleton may have already the final composition or it is an intermediate product that reacts chemically with some element of the skeleton body so that, in fact, the final product is composed of a second non-metallic, inorganic network that has become integral with the porous skeleton as originally produced.
  • silicate water glass, glass, enamel or the like.
  • other salts such as chlorides or aluminates, can be used.
  • Molten metal or a metal alloy can be used also for impregnation, such as aluminum, magnesium, individually or an aluminum silicon alloy or an aluminum titanium alloy.
  • impregnating metals penetrate the pores of the skeleton body and are changed into non-metallic compounds within the pores. For example, these metals are caused to react with carbon, oxygen and/or nitrogen, so as to produce carbides, oxides or nitrides. These reactions require some annealing.
  • the reaction material carbon etc.
  • carbon or nitrogen may be present prior to impregnation in the metal part of the skeleton, or oxygen may be formed on the surface of the pores, for example, as an oxide skin of the metal of the porous skeleton body.
  • the skeleton can be treated with a watery solution from which salt or an oxide thereof has precipitated, and the oxygen thereof will react subsequently with metal caused to penetrate the pores.
  • Including the reaction material in or on the pores of the skeleton is also applicable if the skeleton body is subsequently impregnated with silicate, e.g., for improving the wettability or for reducing viscosity of the principle impregnating material, or the softening point after impregnating is to be increased.
  • the tool is to be used at a temperature, generally, that is below the melting point of the non-metallic material that penetrates the pores of the skeleton; however, for a short period of time, operating temperature may be somewhat above that melting point, particularly if the strength of the metallic skeleton is sufficient to sustain that hot temperature.
  • the heat of fusion serves as local heat sink and the improved thermal conduction facilitates withdrawal and transfer of heat from the surface of the tool that is subjected immediately to the hot working temperature.
  • the non-metallic material in the network of pores must not react chemically, at least not strongly react chemically, during subsequent use with material worked by the tool or die, nor must subsequent exposure of the tool or die to a working material cause the removal of the non-metallic material from the pores in the metallic skeleton.
  • the tool made in accordance with the present invention differs from the form parts made in accordance with known impregnating methods. It should be mentioned that impregnating a porous metal skeleton with a liquidous metal such as copper is known, however, in that case, two intertwining metal networks are produced. Also, it is known to penetrate metallic skeletons with grease or oil or with watery solutions, but penetration and impregnation in this case has an entirely different purpose. The resulting form parts are not comparable in any way with the tools made in accordance with the present invention.
  • Texture and microstructure consisted actually almost completely of so-called nongenuine nitrogen perlite or nitrogen pearloid having a finely laminated texture composition of chromium nitrate Cr N and an austenitic base. That body had high temperature resistance and hot strength.
  • This annulus constituted the skeleton and was placed into a vacuum furnace, above a supply of silicate (water glass), and was heated together therewith to a temperature of l,000 to 1,050 C using a nitrogen atmosphere at about 600 torr (or about 1 16 pounds per square inch). The viscosity of the silicate was sufficiently low for that temperature.
  • the furnace was evacuated and the skeleton was dipped into the molten silicate. Again, the furnace was filled with nitrogen at a pressure of 700 torr. The annulus remained submerged in the molten silicate for about minutes, while molten, low viscosity silicate penetrated the pores of the annulus. Thereafter, the annulus was removed from the silicate but not from the furnace. Heat was maintained in the furnace for about l0 minutes longer, before being turned off. This, then, completed the making of a die to be used for extrusion molding.
  • Method of making a tool comprising the steps of compressing and sintering chromium-nickel-steel particles to obtain a porous skeleton of not more than 50 percent pore volume; sintering the skeleton; nitrating the skeleton to obtain chromium-nitride with at least 1 percent N in the skeleton; impregnating the skeleton with molten silicate to fill at least some of the pores and annealing the skeleton in a nitrogen atmosphere.
  • Method as in claim 1 providing surface zones of the skeleton with a relatively high porosity for a depth of about 5 to 10 millimeter, the interior having relative density of at least 90 percent, and filling only the surface zones with said molten material.
  • the method of making a tool comprising the steps of making a skeleton by compressing steel particles such as powder or flaky shavings to form a porous skeleton penetrated by a continuous network of pores of total volume not exceeding 50 percent, said steel parti cles containing at least one element selected from the group consisting of carbon, nitrogen and oxygen;
  • a molten material selected from the group consisting of silicates, metals and metal alloys having an affinity to said carbon, nitrogen and oxygen to form respectively a carbide, nitride or oxide, for a period sufficient to cause the molten material to penetrate the pores; and
  • Method as in claim 3 providing the porous metal alloy with an approximately uniform distribution of pores and a pore volume of about 20 to 30 percent.
  • Method as in claim 3 providing surface zones of the skeleton with a relatively high porosity for a depth of about 5 to 10 millimeter, the interior having relative density of at least 90 percent, and filling only the surface zones with said molten material.
  • the filler being formed by dipping the skeleton into one of the materials selected from the group consisting of molten aluminum, magnesium, aluminum-silicon alloys and aluminum-titanium alloys.
  • the particles further include up to 2 percent Nb, up to 3 percent Mo, up to 0.03 percent BZr, the iron content being lower accordingly.
  • the tiller made by dipping the skeleton into a molten material selected from the group consisting of silicate, Mg; Al; Al-Si alloys; or Al-Ti alloys for impregnation; and annealing the impregnated skeleton.
  • the skeleton made by compressing and sintering particles comprising up to 0.5 percent C; 0.2 to 2.0 percent Si; 0.3 to 15 percent Mn; 10 to 25 percent Cr; 4 20 percent Ni; up to 10 percent W; up to 2 percent V; 0.2 to 3.0 percent N, the remainder Fe.
  • the filler made by dipping the skeleton into a molten material selected from the group consisting of silicate; Mg; Al; Al-Si alloys; or Al-Ti alloys for impregnation; and annealing the impregnated skeleton.
  • a molten material selected from the group consisting of silicate; Mg; Al; Al-Si alloys; or Al-Ti alloys for impregnation; and annealing the impregnated skeleton.
  • the skeleton made by compressing and sintering steel particles comprising up to 0.3 percent C; up to 2 percent Si; up to 4.0 percent Mn; up to 22 percent Cr; up to 20 percent Mo; up to 8 percent W; up to l8 percent Co; up to 4 percent Ti; up to percent Al; up to 20 percent Fe; the remainder Ni, but at least 40 percent.
  • Method as in claim 12 dipping the skeleton into one of the molten materials selected from the group consisting of silicate; Mg; Al; Al-Si alloys, and Al-Ti alloys for impregnation; and annealing the impregnated skeleton.
  • the skeleton made by compressing and sintering steel particles comprising up to 0.60 percent C; up to 1 percent Si; 0.5 3 percent Mn; 10 22 percent Cr; 10 20 percent Ni; up to percent W; up to 4 percent Mo; up to 4 percent Nb; up to 4 percent Fe; N not exceeding a few percent; remainder Co, at least 22 percent.
  • Method as in claim 14 dipping the skeleton into one of the molten materials selected from the group consisting of silicate; Mg; Al; Al-Si alloys; and Al-Ti alloys for impregnation; and annealing the impregnated skeleton.
  • the steel of the particles compressed include at least one of the elements selected from the group consisting of carbon and nitrogen for the formation of carbide and nitride.
  • Method of making a tool comprising the steps of compressing chromium-nickel-steel particles such as powder or flaky shavings to obtain a porous skeleton penetrated by a continuous network of pores of a total pore volume below 50 percent;
  • a molten material selected from the group consisting of silicate, a salt such as a chloride and an aluminate.
  • the chromiumnickel-steel comprises up to 0.5 percent C; 0.2 2.0 percent Si; 0.3 to 15 percent Mn; 10 25 percent Cr; 4 to 20 percent Ni; up to 10 percent W; and up to 2 percent V, the remainder being iron, all percentages by weight, the pore volume being about 20 to 30 percent:
  • the chromiumnickel-steel comprises up to 0.5 percent C; 0.2 to 2.0 percent Si; 0.3 to 15 percent Mn; 10 to 25 percent Cr; 4-20 percent Ni; up to 10 percent W; up to 2 percent V; 0.2 to 3.0 percent N, remainder Fe.
  • chromium-nickel-steel comprises up to 0.3 percent C; up to 2 percent Si; up to 4.0 percent Mn; up to 22 percent Cr; up to 20 percent Mo; up to 8 percent W; up to 18 percent Co; up to 4 percent Ti; up to 5 percent Al; up to 20 percent Fe; remainder Ni, but at least 40 percent.
  • chromiumnickel-steel comprises up to 0.60 percent C; up to 1 percent Si; 0.5 3 percent Mn; 10 22 percent Cr; 10 20 percent Ni; up to 15 percent W; up to 4 percent Mo; up to 4 percent Nb; up to 4 percent Fe; N not exceeding a few percent; remainder Co, at least 22 percent.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Powder Metallurgy (AREA)
US00156029A 1970-06-29 1971-06-23 Method of making tools by impregnating a steel skeleton with a carbide, nitride or oxide precursor Expired - Lifetime US3837848A (en)

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DE19702032814 DE2032814C (de) 1970-06-29 Werkzeug

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AT (1) AT305000B (de)
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GB (1) GB1354366A (de)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4738730A (en) * 1986-02-18 1988-04-19 Lindberg Corporation Steam sealing for nitrogen treated ferrous part
RU2136479C1 (ru) * 1998-06-01 1999-09-10 Тульское государственное научно-исследовательское геологическое предприятие Материал матриц алмазного и абразивного инструментов и способ его изготовления
US6110577A (en) * 1997-02-14 2000-08-29 Ngk Insulators, Ltd. Composite material for heat sinks for semiconductor devices and method for producing the same
US20030136482A1 (en) * 2002-01-23 2003-07-24 Bohler Edelstahl Gmbh & Co Kg Inert material with increased hardness for thermally stressed parts
EP1900835A1 (de) * 2006-09-15 2008-03-19 Haynes International, Inc. Für die Festigkeitssteigerung durch Nitride geeignete Kobalt-Chrom-Eisen-Nickel-Legierungen
US7967605B2 (en) 2004-03-16 2011-06-28 Guidance Endodontics, Llc Endodontic files and obturator devices and methods of manufacturing same
US11590571B2 (en) 2019-10-25 2023-02-28 Miba Sinter Austria Gmbh Method for producing a sintered component

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE58908200D1 (de) * 1988-02-25 1994-09-22 Trw Motorkomponenten Gmbh & Co Hartstofflegierung.
US5853506A (en) * 1997-07-07 1998-12-29 Ford Motor Company Method of treating metal working dies

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2672426A (en) * 1950-12-14 1954-03-16 Mallory & Co Inc P R Metal-ceramic bodies and method of making
US3031340A (en) * 1957-08-12 1962-04-24 Peter R Girardot Composite ceramic-metal bodies and methods for the preparation thereof
US3201236A (en) * 1962-08-24 1965-08-17 Engelhard Ind Inc Method of making metal bodies incorporated with non-metallic refractory material andproduct thereof
US3205565A (en) * 1963-01-21 1965-09-14 Clevite Corp Sintered rubbing contact material and method for producing same
US3384464A (en) * 1966-02-16 1968-05-21 Mallory & Co Inc P R Tungsten structures
US3419363A (en) * 1967-05-01 1968-12-31 Nasa Self-lubricating fluoride-metal composite materials

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2672426A (en) * 1950-12-14 1954-03-16 Mallory & Co Inc P R Metal-ceramic bodies and method of making
US3031340A (en) * 1957-08-12 1962-04-24 Peter R Girardot Composite ceramic-metal bodies and methods for the preparation thereof
US3201236A (en) * 1962-08-24 1965-08-17 Engelhard Ind Inc Method of making metal bodies incorporated with non-metallic refractory material andproduct thereof
US3205565A (en) * 1963-01-21 1965-09-14 Clevite Corp Sintered rubbing contact material and method for producing same
US3384464A (en) * 1966-02-16 1968-05-21 Mallory & Co Inc P R Tungsten structures
US3419363A (en) * 1967-05-01 1968-12-31 Nasa Self-lubricating fluoride-metal composite materials

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4738730A (en) * 1986-02-18 1988-04-19 Lindberg Corporation Steam sealing for nitrogen treated ferrous part
US6110577A (en) * 1997-02-14 2000-08-29 Ngk Insulators, Ltd. Composite material for heat sinks for semiconductor devices and method for producing the same
US6479095B1 (en) 1997-02-14 2002-11-12 Ngk Insulators, Ltd. Composite material for heat sinks for semiconductor devices and method for producing the same
RU2136479C1 (ru) * 1998-06-01 1999-09-10 Тульское государственное научно-исследовательское геологическое предприятие Материал матриц алмазного и абразивного инструментов и способ его изготовления
US20030136482A1 (en) * 2002-01-23 2003-07-24 Bohler Edelstahl Gmbh & Co Kg Inert material with increased hardness for thermally stressed parts
US7967605B2 (en) 2004-03-16 2011-06-28 Guidance Endodontics, Llc Endodontic files and obturator devices and methods of manufacturing same
US10052173B2 (en) 2004-03-16 2018-08-21 Guidance Endodontics, Llc Endodontic files and obturator devices and methods of manufacturing same
EP1900835A1 (de) * 2006-09-15 2008-03-19 Haynes International, Inc. Für die Festigkeitssteigerung durch Nitride geeignete Kobalt-Chrom-Eisen-Nickel-Legierungen
US8075839B2 (en) 2006-09-15 2011-12-13 Haynes International, Inc. Cobalt-chromium-iron-nickel alloys amenable to nitride strengthening
US11590571B2 (en) 2019-10-25 2023-02-28 Miba Sinter Austria Gmbh Method for producing a sintered component

Also Published As

Publication number Publication date
FR2099312A5 (de) 1972-03-10
AT305000B (de) 1973-02-12
GB1354366A (en) 1974-06-05
DE2032814A1 (de) 1972-05-04
DE2032814B2 (de) 1972-05-04

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