EP0034330A2 - Process for producing component parts by powder metallurgy - Google Patents

Process for producing component parts by powder metallurgy Download PDF

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Publication number
EP0034330A2
EP0034330A2 EP81100941A EP81100941A EP0034330A2 EP 0034330 A2 EP0034330 A2 EP 0034330A2 EP 81100941 A EP81100941 A EP 81100941A EP 81100941 A EP81100941 A EP 81100941A EP 0034330 A2 EP0034330 A2 EP 0034330A2
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EP
European Patent Office
Prior art keywords
cores
capsule
core
metal powder
powder
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP81100941A
Other languages
German (de)
French (fr)
Other versions
EP0034330A3 (en
Inventor
Wolfgang Dr.-Ing. Betz
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
MTU Aero Engines GmbH
Original Assignee
MTU Motoren und Turbinen Union Muenchen GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by MTU Motoren und Turbinen Union Muenchen GmbH filed Critical MTU Motoren und Turbinen Union Muenchen GmbH
Publication of EP0034330A2 publication Critical patent/EP0034330A2/en
Publication of EP0034330A3 publication Critical patent/EP0034330A3/en
Withdrawn legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F7/00—Elements not covered by group F28F1/00, F28F3/00 or F28F5/00
    • F28F7/02—Blocks traversed by passages for heat-exchange media
    • 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
    • B22F5/10—Manufacture of workpieces or articles from metallic powder characterised by the special shape of the product of articles with cavities or holes, not otherwise provided for in the preceding subgroups
    • 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
    • B22F5/10—Manufacture of workpieces or articles from metallic powder characterised by the special shape of the product of articles with cavities or holes, not otherwise provided for in the preceding subgroups
    • B22F2005/103—Cavity made by removal of insert
    • 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
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F2255/00—Heat exchanger elements made of materials having special features or resulting from particular manufacturing processes
    • F28F2255/18—Heat exchanger elements made of materials having special features or resulting from particular manufacturing processes sintered

Definitions

  • the invention relates to a method for the powder metallurgical production of components with intricate, especially undercut cavities or outer surfaces.
  • the object of the invention is to demonstrate a new method which enables such components to be manufactured economically for series production.
  • cores 2 in the form of parallel rods are used in a capsule 1, preferably made of sheet steel, the interior of which corresponds to the outer surface of the desired component 3 plus - corresponding to the expected shrinkage of the filled capsule - approximately 10 to 20% oversize through known facilities, e.g. B. grid made of steel wire, held in the desired position.
  • these rods are arranged in several layers, namely in layers approximately perpendicular to one another.
  • the arrangement of the straight bars 2 in several layers is illustrated by the inclined image according to FIG. Fig. Lb shows a plan view of bars perpendicular to each other in layers, but these bars are each bent at right angles.
  • the cores are made of ceramic or steel. The core shape corresponds to the desired cavities of the component 3 to be produced.
  • the capsule After inserting the rod-shaped cores according to FIG. 1, the capsule is completely filled with metal powder and compacted by shaking, whereupon it is evacuated and sealed vacuum-tight. The contents of the capsule are then sintered or hot isostatically pressed. Finally, the capsule is removed until the core ends are exposed, whereupon the cores are mechanically worked out and / or chemically released.
  • the component in the example of the cross-flow heat exchanger, is now complete along with its entangled cavities.
  • cores 12 made of ceramic or steel are used so that the desired entangled, z. B. undercut outer surface of the component is shown.
  • the cylinder is then completely filled with metal powder and shaken to the desired density, after which it is evacuated and sealed in a vacuum-tight manner. Then the cylinder content is sintered again or hot isostatically pressed. Finally, the cylinder is removed until the core ends are exposed, whereupon the cores are mechanically worked out and / or chemically released. The component and its entangled outer surface are finished.
  • Cores according to FIG. 3 or FIG. 4 are used for the production of hollow components with material webs arranged inside. These have essentially the shape of plates 20, 20a, which are provided with openings 21, 22. These cores are placed crosswise one on top of the other, leaving a space between two plates arranged one above the other. The metal powder introduced into the capsule then fills the spaces between the plates 20, 20a arranged one above the other and the openings 21, 22. After the core material has been removed A component 30 then results, as shown in FIG. 3a. This component has a plate-shaped supporting wall and material webs. If not only two but several plate-shaped cores with openings are used, a component with a row of load-bearing partitions and a plurality of nub-like material webs connecting them results.
  • the openings of the plate-shaped core 30 according to FIG. 4 have a lens shape.
  • cores made of Al 2 0 3 are used, which are then dissolved out with alkali lyes. It is also advantageous to use steel cores instead of ceramic cores, since the risk of breakage when shaking the capsule is lower in steel cores than in ceramic cores. If ceramic cores are used, acids can be used as solvents for removing the core material.

Abstract

Powder method for producing component parts with intricate cavities or with highly structured outer surfaces with the aid of metal or ceramic cores which, after compaction and sintering or hot isostatic pressing, are freed mechanically or chemically, the desired cavities thereby being produced. <IMAGE>

Description

Die Erfindung betrifft ein Verfahren zur pulvermetallurgischen Herstellung von Bauteilen mit verwickelten, vor allem hinterschnittenen Hohlräumen oder Außenflächen.The invention relates to a method for the powder metallurgical production of components with intricate, especially undercut cavities or outer surfaces.

Erfindungsaufgabe ist, ein neues Verfahren aufzuzeigen, das eine für Serienfertigung wirtschaftlich tragbare Herstellung solcher Bauteile ermöglicht.The object of the invention is to demonstrate a new method which enables such components to be manufactured economically for series production.

Diese Aufgabe wird mit den kennzeichnenden Merkmalen des Anspruchs 1 gelöst. Bei Anwendung von Kernen entsprechend Anspruch 3 ergeben sich im Inneren des fertigen Bauteils Materialstege, die als festigkeitserhöhende Mittel von besonderem Vorteil sein können. Der Anspruch 4 gibt besondere Maßnahmen zur wirtschaftlichen Herstellung von Kreuzstrom-Wärmetauschern an, während die Ansprüche 2, 5 und 6 sich mit der Beschaffenheit des Pulvers, des Kerns und des Kernlösungsmittels befassen.This object is achieved with the characterizing features of claim 1. When using cores according to claim 3, there are material webs in the interior of the finished component, which can be of particular advantage as strength-increasing agents. Claim 4 specifies special measures for the economical production of cross-flow heat exchangers, while claims 2, 5 and 6 deal with the nature of the powder, the core and the core solvent.

Die Erfindung wird unter Bezugnahme auf die Zeichnungen anhand von Ausführungsbeispielen erläutert; dabei zeigt

  • Fig. 1, la und 1b die Herstellung eines Kreuzstrom-Wärmetauschers nach dem erfindungsgemäßen Verfahren,
  • Fig. 2 die Herstellung eines Bauteils mit verwickelten Außenflächen,
  • Fig. 3 die Verwendung von Kernen mit Durchbrüchen
  • Fig. 3a ein fertiges Bauteil, wie es mit der Kernanordnung gemäß Fig. 3 herstellbar ist und
  • Fig. 4 einen plattenförmigen Kern mit Durchbrüchen.
The invention is explained with reference to the drawings using exemplary embodiments; shows
  • 1, la and 1b, the production of a cross-flow heat exchanger according to the inventive method,
  • 2 the production of a component with entangled outer surfaces,
  • Fig. 3 shows the use of cores with openings
  • 3a shows a finished component as can be produced with the core arrangement according to FIG. 3 and
  • Fig. 4 shows a plate-shaped core with openings.

Gemäß Fig. 1 werden in eine vorzugsweise aus Stahlblech bestehende Kapsel 1, deren Innenraum der Außenfläche des gewünschten Bauteils 3 zuzüglich-entsprechend dem zu erwartenden Schrumpfmaß der gefüllten Kapsel-etwa 10 bis 20 % Aufmaß entspricht, Kerne 2 in Form von parallelen Stäben eingesetzt und durch bekannte Einrichtungen, z. B. Gitter aus Stahldraht, in der gewünschten Lage gehalten. Für Herstellung eines Kreuzstrom-Wärmetauschers werden diese Stäbe in mehreren Lagen, und zwar lagenweise zueinander etwa senkrecht liegend, angeordnet. Durch das Schrägbild gemäß Fig. la wird die Anordnung der geraden Stäbe 2 in mehreren Lagen verdeutlicht. Fig. lb zeigt eine Draufsicht auf lagenweise zueinander senkrecht verlaufende Stäbe, wobei diese Stäbe allerdings jeweils rechtwinklig gebogen sind. Die Kerne bestehen aus Keramik oder aus Stahl. Die Kernform entspricht den gewünschten Hohlräumen des herzustellenden Bauteils 3.According to FIG. 1, cores 2 in the form of parallel rods are used in a capsule 1, preferably made of sheet steel, the interior of which corresponds to the outer surface of the desired component 3 plus - corresponding to the expected shrinkage of the filled capsule - approximately 10 to 20% oversize through known facilities, e.g. B. grid made of steel wire, held in the desired position. For the production of a cross-flow heat exchanger, these rods are arranged in several layers, namely in layers approximately perpendicular to one another. The arrangement of the straight bars 2 in several layers is illustrated by the inclined image according to FIG. Fig. Lb shows a plan view of bars perpendicular to each other in layers, but these bars are each bent at right angles. The cores are made of ceramic or steel. The core shape corresponds to the desired cavities of the component 3 to be produced.

Nach dem Einsetzen der stabförmigen Kerne gemäß Fig. 1 wird die Kapsel vollständig mit Metallpulver gefüllt und durch Rütteln verdichtet, worauf sie evakuiert und vakuumdicht verschlossen wird. Sodann wird der Kapselinhalt gesintert oder heißisostatisch qepreßt. Schließlich wird die Kapsel bis zur Freilegung der Kernenden entfernt, worauf die Kerne mechanisch herausgearbeitet und/oder chemisch herausgelöst werden. Das Bauteil, im Beispiel der Kreuzstrom-Wärmetauscher, ist damit samt seinen verwickelten Hohlräumen fertig.After inserting the rod-shaped cores according to FIG. 1, the capsule is completely filled with metal powder and compacted by shaking, whereupon it is evacuated and sealed vacuum-tight. The contents of the capsule are then sintered or hot isostatically pressed. Finally, the capsule is removed until the core ends are exposed, whereupon the cores are mechanically worked out and / or chemically released. The component, in the example of the cross-flow heat exchanger, is now complete along with its entangled cavities.

Gemäß Fig. 2 werden in einem aus Stahlblech bestehenden Zylinder 11, dessen Innenraum der größten Außenfläche des gewünschten Bauteils 13 zuzüglich etwa 10 bis 20 % Aufmaß entspricht, Kerne 12 aus Keramik oder Stahl so eingesetzt, daß die gewünschte verwickelte, z. B. hinterschnittene Außenfläche des Bauteils dargestellt ist. Hierauf wird wieder der Zylinder vollständig mit Metallpulver gefüllt und auf die gewünschte Dichte gerüttelt, worauf er evakuiert und vaktumdicht verschlossen wird. Sodann wird wieder der Zylinderinhalt gesintert oder heißisostatisch gepreßt. Schließlich wird der Zylinder bis zur Freilegung der Kernenden entfernt, worauf die Kerne mechanisch herausgearbeitet und/oder chemisch herausgelöst werden. Das Bauteil samt seiner verwickelten Außenfläche ist damit fertig.2, in a steel sheet cylinder 11, the interior of which corresponds to the largest outer surface of the desired component 13 plus about 10 to 20% oversize, cores 12 made of ceramic or steel are used so that the desired entangled, z. B. undercut outer surface of the component is shown. The cylinder is then completely filled with metal powder and shaken to the desired density, after which it is evacuated and sealed in a vacuum-tight manner. Then the cylinder content is sintered again or hot isostatically pressed. Finally, the cylinder is removed until the core ends are exposed, whereupon the cores are mechanically worked out and / or chemically released. The component and its entangled outer surface are finished.

Für die Herstellung von hohlen Bauteilen mit im Inneren angeordneten Materialstegen werden Kerne gemäß Fig. 3 oder Fig. 4 verwendet. Diese haben im wesentlichen die Form von Platten 20, 20a, die mit Durchbrüchen 21, 22 versehen sind. Diese Kerne werden kreuzweise übereinandergelegt, wobei zwischen jeweils zwei übereinander angeordneten Platten ein Zwischenraum gelassen wird. Das in die Kapsel- eingebrachte Metallpulver füllt dann die Zwischenräume zwischen den übereinander angeordneten Platten 20, 20a aus und die Durchbrüche 21, 22. Nach den Herauslösen des Kernmaterials ergibt sich dann ein Bauelement 30, wie es in Fig. 3a dargestellt ist. Dieses Bauelement weist eine plattenförmige tragende Wand und Materialstege auf. Werden nicht nur zwei sondern mehrere plattenförmige mit Durchbrüchen versehene Kerne verwendet, so ergibt sich ein Bauteil mit einer Reihe von tragenden Zwischenwänden und einer Vielzahl dieser verbindende noppenartige Materialstege.Cores according to FIG. 3 or FIG. 4 are used for the production of hollow components with material webs arranged inside. These have essentially the shape of plates 20, 20a, which are provided with openings 21, 22. These cores are placed crosswise one on top of the other, leaving a space between two plates arranged one above the other. The metal powder introduced into the capsule then fills the spaces between the plates 20, 20a arranged one above the other and the openings 21, 22. After the core material has been removed A component 30 then results, as shown in FIG. 3a. This component has a plate-shaped supporting wall and material webs. If not only two but several plate-shaped cores with openings are used, a component with a row of load-bearing partitions and a plurality of nub-like material webs connecting them results.

Setzt man in eine Kapsel nur einen plattenförmigen Kern 20 ein, so läßt sich ein Bauteil mit außen geschlossenen Wänden und innenliegendem Hohlraum erzeugen, wobei die Wände durch Materialstege miteinander verbunden sind. Die Durchbrüche des plattenförmigen Kerns 30 gemäß Fig. 4 haben Linsenform.If only one plate-shaped core 20 is inserted into a capsule, a component with externally closed walls and an internal cavity can be produced, the walls being connected to one another by material webs. The openings of the plate-shaped core 30 according to FIG. 4 have a lens shape.

Bei Verwendung eines Ni-Basis-Pulvers werden Kerne aus Al203 benützt, die dann mit Alkali-Laugen herausgelöst werden. Vorteilhaft ist auch die Verwendung von Stahlkernen anstelle von Keramikkernen, da bei Stahlkernen die Gefahr eines Bruches beim Rütteln der Kapsel geringer ist als bei Keramikkernen. Werden Keramikkerne verwendet, so kommen als Lösungsmittel zum Herauslösen des Kernmaterials Säuren in Betracht.When using a Ni-based powder, cores made of Al 2 0 3 are used, which are then dissolved out with alkali lyes. It is also advantageous to use steel cores instead of ceramic cores, since the risk of breakage when shaking the capsule is lower in steel cores than in ceramic cores. If ceramic cores are used, acids can be used as solvents for removing the core material.

Claims (6)

1. Verfahren zur pulvermetallurgischen Herstellung von Bauteilen mit verwickelten (kompliziert geformten) Hohlräumen oder mit stark strukturierten Außenflächen mit Hilfe von Kernen, dadurch gekennzeichnet, daß a) in eine Kapsel (1) zumindest ein Kern (2) aus Keramik oder Metall eingesetzt und verankert wird, dessen Form dem gewünschten Hohlraum bzw. den gewünschten Ausnehmungen an der Außenfläche des Bauteils (3) entspricht; b) hierauf wird die Kapsel (1) mit Metallpulver völlig gefüllt und zur Verdichtung des Metallpulvers ge-rüttelt; c) die Kapsel wird evakuiert und vakuumverschlossen; d) es wird bei erhöhter Temperatur gesintert oder heißisostatisch gepreßt; e) die Kapsel (1) wird entfernt und die Enden des bzw. der Kerne(s) werden freigelegt; f) der Kern bzw. die Kerne werden mit bekannten Verfahren mechanisch oder chemisch herausgelöst. 1. A process for the powder metallurgical production of components with intricate (intricately shaped) cavities or with highly structured outer surfaces with the aid of cores, characterized in that a) at least one core (2) made of ceramic or metal is inserted and anchored in a capsule (1), the shape of which corresponds to the desired cavity or the desired recesses on the outer surface of the component (3); b) the capsule (1) is then completely filled with metal powder and g -shaken to compress the metal powder; c) the capsule is evacuated and vacuum-sealed; d) it is sintered at high temperature or hot isostatically pressed; e) the capsule (1) is removed and the ends of the core (s) are exposed; f) the core or cores are extracted mechanically or chemically using known methods. 2. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß das Kernmaterial so beschaffen ist, daß es bei Verdichtungs- oder Sintertemperatur der Pulverschüttung formstabil bleibt.2. The method according to claim 1, characterized in that the core material is such that it at The compression or sintering temperature of the powder filling remains dimensionally stable. 3. Verfahren nach Anspruch 1 oder 2, dadurch gekennzeichnet, daß Kerne mit Durchbrüchen verwendet werden (Fig. 3 und Fig. 4).3. The method according to claim 1 or 2, characterized in that cores with openings are used (Fig. 3 and Fig. 4). 4. Anwendung des Verfahrens nach den Ansprüchen 1 bis 3, zur Herstellung eines Kreuzstrom-Wärmetauschers, dadurch gekennzeichnet, daß als Kerne gebogene Stäbe (Fiq. 1b) oder gerade parallele Stäbe (Fig. 1, la) in mehreren Lagen verwendet werden, die lagenweise zueinander etwa senkrecht stehen.4. Application of the method according to claims 1 to 3, for the production of a cross-flow heat exchanger, characterized in that bent rods (Fig. 1b) or straight parallel rods (Fig. 1, la) are used in several layers as cores are approximately perpendicular to each other in layers. 5. Verfahren nach den Ansprüchen 1 bis 4, dadurch gekennzeichnet, daß bei Verwendung eines Metall-Pulvers auf Ni-Basis Kerne aus A1203 benützt werden, die dann mit Alkali-Laugen herausgelöst werden.5. Process according to claims 1 to 4, characterized in that when using a metal powder based on Ni, cores are used from A1 2 0 3 , which are then dissolved out with alkali bases. 6. Verfahren nach den Ansprüchen 1 bis 3, dadurch ge-kennzeichnet, daß bei Verwendung eines Metall-Pulvers auf Ni-Basis Stahl kerne benutzt werden, die mit Säuren vorzugsweise HCL herausgelöst werden.6. The method according to claims 1 to 3, characterized g e-indicates that when using a metal powder on Ni-based steel cores are used, which are preferably dissolved with acids HCL.
EP81100941A 1980-02-14 1981-02-11 Process for producing component parts by powder metallurgy Withdrawn EP0034330A3 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3005474A DE3005474C2 (en) 1980-02-14 1980-02-14 Process for the powder metallurgical production of one-piece components with entangled cavities
DE3005474 1980-02-14

Publications (2)

Publication Number Publication Date
EP0034330A2 true EP0034330A2 (en) 1981-08-26
EP0034330A3 EP0034330A3 (en) 1981-12-16

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EP81100941A Withdrawn EP0034330A3 (en) 1980-02-14 1981-02-11 Process for producing component parts by powder metallurgy

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JP (1) JPS56127703A (en)
DE (1) DE3005474C2 (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0356745A1 (en) * 1988-08-20 1990-03-07 Schwäbische Hüttenwerke Gesellschaft mit beschränkter Haftung Heat transfer device
EP1172165A1 (en) * 2000-07-15 2002-01-16 Schott Glas Process for manufacturing coolant channels in thermally stressed forming tools and forming tools obtained thereby
CN105798296A (en) * 2016-03-23 2016-07-27 上海工程技术大学 Preparing method for 3D printing boron carbide/aluminum composite special-shaped component

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US4861546A (en) * 1987-12-23 1989-08-29 Precision Castparts Corp. Method of forming a metal article from powdered metal
CH677488A5 (en) * 1989-02-14 1991-05-31 Htm Ag
JP3332081B2 (en) 1999-09-07 2002-10-07 日本ピラー工業株式会社 Mold for manufacturing fuel cell separator and method for manufacturing fuel cell separator
US8033805B2 (en) * 2007-11-27 2011-10-11 Kennametal Inc. Method and apparatus for cross-passageway pressing to produce cutting inserts
JP2016017218A (en) * 2014-07-10 2016-02-01 株式会社Ihi Manufacturing method for hallow structure
GB2620549A (en) * 2022-06-27 2024-01-17 The Manufacturing Tech Centre Limited A method for creating an object

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FR2225240A1 (en) * 1973-04-12 1974-11-08 Crucible Inc
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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0356745A1 (en) * 1988-08-20 1990-03-07 Schwäbische Hüttenwerke Gesellschaft mit beschränkter Haftung Heat transfer device
EP0467426A2 (en) * 1988-08-20 1992-01-22 Schwäbische Hüttenwerke Gesellschaft mit beschränkter Haftung Heat exchange apparatus
EP0467426A3 (en) * 1988-08-20 1992-03-11 Schwaebische Huettenwerke Gesellschaft Mit Beschraenkter Haftung Heat exchange apparatus
EP1172165A1 (en) * 2000-07-15 2002-01-16 Schott Glas Process for manufacturing coolant channels in thermally stressed forming tools and forming tools obtained thereby
CN105798296A (en) * 2016-03-23 2016-07-27 上海工程技术大学 Preparing method for 3D printing boron carbide/aluminum composite special-shaped component

Also Published As

Publication number Publication date
DE3005474C2 (en) 1982-11-11
DE3005474A1 (en) 1981-08-20
JPS56127703A (en) 1981-10-06
EP0034330A3 (en) 1981-12-16

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