DE2343680A1 - Hot pressure flat shapes from powders, esp. silicon nitride - using graphite die design for uniform temp. distribution - Google Patents

Hot pressure flat shapes from powders, esp. silicon nitride - using graphite die design for uniform temp. distribution

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Publication number
DE2343680A1
DE2343680A1 DE19732343680 DE2343680A DE2343680A1 DE 2343680 A1 DE2343680 A1 DE 2343680A1 DE 19732343680 DE19732343680 DE 19732343680 DE 2343680 A DE2343680 A DE 2343680A DE 2343680 A1 DE2343680 A1 DE 2343680A1
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Germany
Prior art keywords
graphite
press
heating
powders
die
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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.)
Pending
Application number
DE19732343680
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German (de)
Inventor
Michael Applin
Friedrich Krall
Thomas Dr Nesse
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.)
Evonik Operations GmbH
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Degussa GmbH
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Publication date
Application filed by Degussa GmbH filed Critical Degussa GmbH
Priority to DE19732343680 priority Critical patent/DE2343680A1/en
Publication of DE2343680A1 publication Critical patent/DE2343680A1/en
Pending legal-status Critical Current

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    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/515—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics
    • C04B35/58—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics based on borides, nitrides, i.e. nitrides, oxynitrides, carbonitrides or oxycarbonitrides or silicides
    • C04B35/584—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics based on borides, nitrides, i.e. nitrides, oxynitrides, carbonitrides or oxycarbonitrides or silicides based on silicon nitride
    • C04B35/593—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics based on borides, nitrides, i.e. nitrides, oxynitrides, carbonitrides or oxycarbonitrides or silicides based on silicon nitride obtained by pressure sintering
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
    • B22F3/12—Both compacting and sintering
    • B22F3/14—Both compacting and sintering simultaneously
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B28—WORKING CEMENT, CLAY, OR STONE
    • B28B—SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER
    • B28B3/00—Producing shaped articles from the material by using presses; Presses specially adapted therefor
    • B28B3/02—Producing shaped articles from the material by using presses; Presses specially adapted therefor wherein a ram exerts pressure on the material in a moulding space; Ram heads of special form
    • B28B3/025—Hot pressing, e.g. of ceramic materials
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B30—PRESSES
    • B30B—PRESSES IN GENERAL
    • B30B15/00—Details of, or accessories for, presses; Auxiliary measures in connection with pressing
    • B30B15/34—Heating or cooling presses or parts thereof
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/64—Burning or sintering processes
    • C04B35/645—Pressure sintering

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Ceramic Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Structural Engineering (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Powder Metallurgy (AREA)
  • Press-Shaping Or Shaping Using Conveyers (AREA)

Abstract

Flat mouldings are mfd. from powders or granules using hot pressing, esp. the prodn. of Si3N4 or other ceramic compacts. The heating is applied solely by the punches in the die, and in such a way that a uniform temp. is obtd. over the entire cross-section of the compact. Heating is pref. applied by graphite elements located in cavities in graphite punches, using graphite plates of high thermal conductivity, and contg. cavities, on both sides of the compact for better heat-distribution; plates of loose graphite felt are also used between the graphite punches and the punches on press. The uniform temp. obtd. by this process produces uniform mechanical properties right across the cross-section of the compacts.

Description

DEUTSCHE GOLD- UND SILBER-SCIIEIDEANSTALT VORMALS ROESSLER Frankfurt/Main, Weißfrauenstrasse 9GERMAN GOLD AND SILVER SCIIEIDEANSTALT FORMERLY ROESSLER Frankfurt / Main, Weißfrauenstrasse 9

Verfahren und Vorrichtung zur Herstellung von flachen FormkörpernMethod and device for the production of flat moldings

aus Pulvern oder Granulaten.from powders or granules.

Die Erfindung bezieht sich auf ein Ileisspress-Verfahren und eine Vorrichtung zur Herstellung flacher Formkörper aus Pulvern oder Granulaten, insbesondere zur Herstellung von flachen Formkörpern aus Siliziumnitrid und sonstigen keramischen Materialien.The invention relates to an Ileisspress method and a Device for the production of flat moldings from powders or granules, in particular for the production of flat moldings made of silicon nitride and other ceramic materials.

Es ist bekannt, dass sich Siliziumnitrid-Pulver unter Druck bei geeigneter Temperatur und Zugabe von Sinterhilfsmitteln zu festen Körpern aus Siliziumnitrid mit nahezu theoretischer Dichte verpressen lassen, üblicherweise wird dazu das Pulver in Matrizen aus Graphit zwischen zwei Graphitstempeln verdichtet. Während der Druckerhöhung wird die Temperatur des Pulvers nach einem geeigneten zeitlichen Programm gesteigert. Die Beheizung des Pulvers erfolgt von aussen durch Wärmeleitung von der Graphit-Matrize und dem Preßstempel aus, wobei diese Graphitteile induktiv oder im direkten Stromdurchgang oder auch durch aussen angeordnete Heizrohre auf entsprechende Temperatüren gebracht werden. Diese Beheizungsverfahren haben jedoch alle den Nachteil, dass bei g.rösseren Abmessungen, insbesondere bei flachen Formen der zu pressenden Formkörper, die Temperaturverteilung im Pressling und damit die Festigkeit des fertigen Teiles ungleichmässig ist. Dies ist zu erklären entweder durch eine ungleichmässige Stromwärmeerzeugung in den unterschiedlichen Querschnitten der Graphitteile der Matrize und der Preßstempel oder auch durch die ungünstige Weglängen- und Geometrieverhältnisse zwisehen dem Wärmezuführungsbereich über die Schmalseiten des Presslings undIt is known that silicon nitride powder can be pressurized when appropriate Press temperature and addition of sintering aids to solid bodies made of silicon nitride with almost theoretical density leave, usually the powder is in matrices made of graphite compressed between two graphite stamps. During the pressure increase, the temperature of the powder increases after a appropriate timed program increased. The powder is heated from the outside through heat conduction from the graphite die and the ram, these graphite parts inductively or in the direct passage of current or through externally arranged Heating pipes are brought to the appropriate temperature. These However, heating methods all have the disadvantage that with larger dimensions, especially with flat shapes, the too pressing molded body, the temperature distribution in the compact and thus the strength of the finished part is uneven is. This can be explained either by an uneven electricity heat generation in the different cross-sections of the Graphite parts of the die and the ram or the unfavorable path length and geometry conditions between the Heat supply area over the narrow sides of the compact and

509817/0366509817/0366

dem Wärmeabstrahlungsbereich über seine verhältnismässig grossen Stirnseiten zu den relativ kälteren und/oder massiveren Preßstempeln. the heat radiation area via its relatively large end faces to the relatively colder and / or more massive press rams.

Es war daher Aufgabe der vorliegenden Erfindung, ein Verfahren und eine Vorrichtung zu finden, mit deren Hilfe sich beim Heisspressen flacher Formkörper eine gleichmässige Temperaturverteilung und damit eine gleichmässige mechanische Festigkeit der Fertigprodukte erreichen lässt.It was therefore an object of the present invention to provide a method and to find a device with the help of which a uniform temperature distribution is achieved when hot-pressing flat shaped bodies and thus a uniform mechanical strength of the finished products can be achieved.

Diese Aufgabe wurde erfindungsgeraäss dadurch gelöst, dass bei der Herstellung flacher, heissgepresster Formkörper aus Pulvern oder Granulaten, insbesondere zur Herstellung von Formkörpern aus Siliziumnitrid oder sonstigen keramischen Materialien, die Beheizung des Presskörpers ausschliesslieh über die Preßstempel und damit über die beiden Stirnflächen des Presslings erfolgt, derart, dass sich ihi Pressling eine gleichmässige Temperatur über den gesamten Querschnitt einstellt.This object was achieved according to the invention in that the Production of flat, hot-pressed moldings from powders or granules, in particular for the production of moldings from Silicon nitride or other ceramic materials, the heating of the press body exclusively via the press ram and thus takes place over the two end faces of the compact in such a way that the compact has a uniform temperature adjusts the entire cross-section.

Es hat sich gezeigt, dass es am vorteilhaftesten ist, die Graphitstempel mit Aussparungen zu versehen, in denen sich Heizkörper aus Graphit befinden, die durch Wärmestrahlung und gegebenenfalls - bei Arbeiten unter Schutzgas - durch Konvektion die Aufheizung der Graphitstempel bewirken. Durch geeignete Wahl von Anzahl und Anordnung der Aussparungen und Heizkörper kann erreicht werden, dass die Wärmeleitung vorzugsweise in Richtung zum Pressgut erfolgt und dass sich an der dem Pressling zugewandten Seite des Preßstempels eine nahezu homogene Temperaturverteilung einstellt. Und dies gilt im Gegensatz zur Aufheizung durch direkten Stromdurchgang oder durch induktive Erwärmung oder sonstige Aufheizverfahren von der äusseren Matrize her für jede Stellung des Preßstempels zur umgebenden Graphitmatrize.It has been shown that it is most beneficial to use the graphite stamp to be provided with recesses, in which there are radiators made of graphite, which by thermal radiation and possibly - when working under protective gas - cause the graphite stamp to heat up by convection. By suitable choice of number and arrangement of the recesses and heating elements, it can be achieved that the heat conduction preferably takes place in the direction of the material to be pressed and that a virtually homogeneous temperature distribution is established on the side of the press ram facing the compact. And this applies in contrast to heating by direct passage of current or by inductive heating or other heating methods from the outer die for every position of the ram in relation to the surrounding graphite die.

509817/0366509817/0366

Die Homogenität der Temperaturverteilung kann noch weiter gesteigert werden durch Einlegung von dünnen, besonders gut wärmeleitenden Graphitausgleichsplatten zwischen Preßstempel und Pressling. Diese Ausgleichsplatten können weiterhin durch Aussparungen oaer Hohlräume an solchen Stellen, an denen erfahrungsgemäss die höheren Temperaturen im Pressling auftreten, wie z.B. in der mittleren Zone, in ihrer Wärmeleitfähigkeit entsprechend beeinflusst werden, so dass sich an der Kontaktfläche zwischen Ausgleichsplatte und Pressling eine vollkommen homogene Temperatur über dem gesamten Querschnitt bei homogener Druckverteilung einstellt. The homogeneity of the temperature distribution can be increased even further are made by inserting thin, particularly good heat-conducting graphite compensation plates between the ram and Pellet. These compensating plates can continue to have recesses oaer cavities in those places where experience has shown the higher temperatures in the pellet occur, e.g. in the middle zone, in their thermal conductivity accordingly can be influenced so that a completely homogeneous temperature is created at the contact surface between the compensating plate and the compact adjusts over the entire cross-section with homogeneous pressure distribution.

Das erfindungsgemässe Verfahren hat weitere Vorteile: Während bei induktiver Matrizenbeheizung die Matrizenabmessungen einen Kompromiss darstellen, einerseits zwischen möglichst geringer Wanddicke und Matrizenhöhe wegen der guten Wärmeausnutzung und andererseits zwischen möglichst grosser Wanddicke und Matrizenhöhe wegen der nötigen mechanischen Festigkeit, kann bei der eriindungsgomassen Beheizung die Matrizengeometrie beliebig und ausschliesslich den Festigkeitsanforderungen genügend ausgeführt werden. Es ist dadurch z.B. möglich, durch Umwickeln der Matrize mit vorgespannten Kohlenstoffasern , deren äussere Abmessungen ohne Festigkeitseinbusse und ohne Störung der homogenen Temperaturverteilung im Pressling auf nahezu beliebige Werte zu verringern, wobei die Matrizenwandstärke lediglich von Anzahl, Vorspannung und Festigkeit der Kohlenstoffasern und dem Wickelverfahren bestimmt wird.The method according to the invention has further advantages: While with inductive die heating, the die dimensions represent a compromise, on the one hand between being as small as possible Wall thickness and die height because of the good heat utilization and on the other hand between the greatest possible wall thickness and die height Because of the necessary mechanical strength, can be used in the invention The die geometry is heated in any way and only adequately designed to meet the strength requirements will. This makes it possible, for example, by wrapping the die with pre-tensioned carbon fibers, the external dimensions of which are without Loss of strength and without disturbance of the homogeneous temperature distribution in the pressed part to be reduced to almost any value, whereby the die wall thickness only depends on the number, pretension and strength of the carbon fibers and the winding process are determined will.

Diese Ausgestaltung der Pressmatrize ermöglicht eine wesentliche Reduzierung der Gesamtmasse der erforderlichen Graphitteile und damit eine Verkürzung der Presszyklen durch sehnellere Aufheiz- und Abkühlzeiten verbunden mit einer Energieeinsparung.This configuration of the press die enables a significant reduction in the total mass of the required graphite parts and thus a shortening of the pressing cycles through much shorter heating and cooling times combined with energy savings.

509817/0-166509817 / 0-166

Die Aufheizzeiten können ausserdera dadurch weiter reduziert werden, dass zwischen den Graphitstempeln und den Stahlstempeln der Presse lockere Graphitfilzplatten zwischengelegt werden, die während der drucklosen Aufheizphase Wärineverluste über die massiven Stahlstempel der Tresse verringern.The heating times can also be further reduced, that between the graphite punches and the steel punches of the press loose graphite felt plates are placed in between, which during the unpressurized heating phase through the massive heat losses Reduce the steel stamp of the braid.

Ausserdem hat sich gezeigt, dass durch Strompulsierung während des Aufheizvorganges bei dieser Anordnung Wärmespitzen besonders leicht abgebaut werden können.In addition, it has been shown that through current pulsation during the Heating process with this arrangement, heat peaks can be reduced particularly easily.

Abbildung 1 zeigt schematisch eine erfindungsgemässe Vorrichtung.Figure 1 shows schematically a device according to the invention.

Die erfindungsgemässe Vorrichtung besteht aus einer Pressmatrize aus Graphit, die mit vorgespannten Kohlenstoffasern 2 verstärkt ist. Beiderseits des Presslings 3 befinden sich Ausgleichsplatten aus Graphit, mit Aussparungen 5 zur Einstellung einer homogenen Temperaturverteilung im Pressling 3· Die Beheizung des Presslings 3 erfolgt über Heizkörper 6 aus Graphit, die in Aussparungen der Graphitpreßstempel 8 liegen, weitere Aussparungen 9 dienen der homogenen Temperaturverteilung. Zwischen den Graphitpreßstempeln α und den Preßstempeln io der Presse befinden sich vorteilhafterweise lockere Graphitfilze 11.The device according to the invention consists of a press die made of graphite which is reinforced with prestressed carbon fibers 2. Compensating plates made of graphite are located on both sides of the pellet 3, with recesses 5 for setting a homogeneous temperature distribution in the pellet 3 Loose graphite felts 11 are advantageously located between the graphite press rams α and the press rams io of the press.

Folgende Beispiele sollen die Vorteile des erfindungsgemässen Verfahrens aufzeigen:The following examples are intended to demonstrate the advantages of the inventive Show procedure:

Beispiel 1example 1

In einer Heisspresse nach Abbildung 1 wurde Siliziumnitridpulver unter Zugabe bekannter Sinterhilfsmittel zu Presslingen der Ab-r messung 100 χ 100 χ 10 nmr verdichtet. Hieraus wurden zehn Stabproben geschnitten, deren Biegebruchfestigkeits- und schlagfestigkeitswerte um weniger als 1 c/0 voneinander abwichen und im MittelIn a hot press according to Figure 1, silicon nitride powder was compacted with the addition of known sintering aids to form pellets measuring 100 100 χ 10 nmr. Ten rod samples were cut from this, the flexural strength and impact strength values of which differed by less than 1 c / 0 and on average

ο οο ο

9;i,8 kp/inin" bzw. 11,35 kp cm/cm*" betrugen.9 ; i, 8 kg / in "and 11.35 kg / cm *", respectively.

509817/0 3 66 ~5~509817/0 3 66 ~ 5 ~

Darüber hinaus wurde die Dichte von Proben ermittelt, die von nenn- verschiedenen stellen des Presslings stammten. Auch hier ergaben sich nur Dichteabweichungen von weniger als 10,3 fo für Werte zwischen 3,192 und 3,204 g/cnr.In addition, the density of samples was determined which came from nominally different locations on the pellet. Here, too, there were only density deviations of less than 10.3 fo for values between 3.192 and 3.204 g / cnr.

Beispiel 2Example 2

Aus Siliziumnitrid-Pulver wurden durch. Zugabe von Sinterhilf sniittelnMade of silicon nitride powder were made by. Addition of sintering aids

•7.• 7.

stabförmige Presslinge mit den Abmessungen 150 χ 9 x 6 mm in einer erfindungsgemässen Heisspresse verpresst. Die Dichte der Proben schwankte auf der gesamten Länge um weniger als 0,3 c,o. Die Festigkeitswerte lagen von Pressling zu Pressling um weniger βίε 3 % auseinander.Rod-shaped pellets with the dimensions 150 χ 9 x 6 mm are pressed in a hot press according to the invention. The density of the samples fluctuated by less than 0.3 c , o over the entire length. The strength values differed by less than 3 % from compact to compact.

Ausser Siliziumnitrid können nach dem erfindungsgemässen Verfahi-en natürlich auch sonstige keramische Materialien, wie z.B. Aluminiumoxid, metallische Werkstoffe oder Cermets verpresst werden.In addition to silicon nitride, according to the method according to the invention of course also other ceramic materials, such as aluminum oxide, metallic materials or cermets are pressed.

- 6 509817/0366 - 6 509817/0366

Claims (5)

PATENTANSPRÜCHEPATENT CLAIMS 1. Verfahren zur Herstellung von flachen Formkörpern aus Pulvern oder Granulaten durch Heisspressen, insbesondere zur Herstellung von flachen Fornikörpern aus Siliziumnitrid oder sonstigen keramischen Materialien, dadurch gekennzeichnet, dass die Beheizung des zu pressenden Pulvers oder Granulats ausschliesslich über die Preßstempel erfolgt und zwar derart, dass sich im Pressling eine gleichmässige Temperatur über den gesamten Querschnitt einstellt.1. A method for the production of flat molded bodies from powders or granules by hot pressing, in particular for the production of flat molded bodies made of silicon nitride or other ceramic materials, characterized in that the heating of the powder or granules to be pressed takes place exclusively via the press ram in such a way that A uniform temperature over the entire cross-section is established in the pellet. 2. Verfahren nach Anspruch 1, dadurch gekennzeichnet, dass die Beheizung über Graphitheizkörper erfolgt, die sich in entsprechenden Aussparungen der Graphitpreßstempel befinden.2. The method according to claim 1, characterized in that the heating takes place via graphite heating elements, which are located in corresponding recesses in the graphite die. 3· Verfahren nach den Ansprüchen 1 und 2, dadurch gekennzeichnet, dass zwischen Pressling und Preßstempel besonders gut wärmeleitende Graphitplatten eingelegt werden, die zur besseren Homogenität der Temperaturverteilung mit Aussparungen oder Hohlräumen versehen sein können.3. The method according to claims 1 and 2, characterized in that graphite plates with particularly good thermal conductivity are inserted between the pressed part and the ram, which can be provided with recesses or cavities for better homogeneity of the temperature distribution. 4. Verfahren nach den Ansprüchen I bis 3, dadurch gekennzeichnet, dass zwischen den Graphitpreßstempeln und den preßstempeln der Presse lockere Graphitfilzplatten eingelegt werden.4. The method according to claims I to 3, characterized in that loose graphite felt plates are inserted between the graphite press rams and the press rams of the press. 5. Vorrichtung zur Herstellung von flachen Formkörpern nach den Ansprüchen 1 bis k, dadurch gekennzeichnet, dass der Pressling 3 sich in einer Graphitmatrize (l)befindet und die Beheizung des Presslings (3) ausschliesslich über die Graphitpreßstempel (8) erfolgt, vorzugsweise mittels Graphitheizkörper (6), die sich in entsprechenden Aussparungen (7) der Graphitpreßstempel (8) befinden, und gegebenenfalls zwischen dem Pressling (3) und den Graphitpreßstempeln (8) mit Aus-5. Device for the production of flat molded bodies according to claims 1 to k, characterized in that the compact 3 is located in a graphite die (l) and the heating of the compact (3) takes place exclusively via the graphite die (8), preferably by means of graphite heating elements (6), which are located in corresponding recesses (7) of the graphite press rams (8), and optionally between the pressed part (3) and the graphite press rams (8) with — 7 —- 7 - S09817/0366S09817 / 0366 sparungen (5) versehene Graphitplatten (;i) und zwischen Graphitpreßstempeln (8) und Preßstempel (10) der Presse lockere Graphitfilzplatten (11) liegen.savings (5) provided with graphite plates (i) and the press loose Graphitfilzplatten (11) are between Graphitpreßstempeln (8) and press ram (10). Frankfurt/Main, 23.b.l973
Dr.Br.-BiFrankfurt / Main, 23.b. 1973
Dr.Br.-Bi $09817/036$$ 09817 / $ 036 Le e rs eLe e rs e iteite
DE19732343680 1973-08-30 1973-08-30 Hot pressure flat shapes from powders, esp. silicon nitride - using graphite die design for uniform temp. distribution Pending DE2343680A1 (en)

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DE19732343680 DE2343680A1 (en) 1973-08-30 1973-08-30 Hot pressure flat shapes from powders, esp. silicon nitride - using graphite die design for uniform temp. distribution

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DE19732343680 DE2343680A1 (en) 1973-08-30 1973-08-30 Hot pressure flat shapes from powders, esp. silicon nitride - using graphite die design for uniform temp. distribution

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DE2343680A1 true DE2343680A1 (en) 1975-04-24

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2602715A1 (en) * 1986-08-14 1988-02-19 Srti Soc Rech Tech Ind Tool with pressing shafts with metal thermal barriers
FR2602714A1 (en) * 1986-08-14 1988-02-19 Srti Soc Rech Tech Ind Tool with pressing shafts with rigid thermal barriers
US4937414A (en) * 1988-09-12 1990-06-26 Perreault David J Wire guide for electrical discharge machining apparatus
EP0443950A1 (en) * 1990-02-23 1991-08-28 Societe Nationale D'etude Et De Construction De Moteurs D'aviation "Snecma" Moulding device of composite material for the hot-pressing of articles from refractory material
AT17830U1 (en) * 2021-10-18 2023-04-15 Iag Ind Automatisierungsgesellschaft M B H Pressing tool for pressing compound mixtures

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2602715A1 (en) * 1986-08-14 1988-02-19 Srti Soc Rech Tech Ind Tool with pressing shafts with metal thermal barriers
FR2602714A1 (en) * 1986-08-14 1988-02-19 Srti Soc Rech Tech Ind Tool with pressing shafts with rigid thermal barriers
US4937414A (en) * 1988-09-12 1990-06-26 Perreault David J Wire guide for electrical discharge machining apparatus
EP0443950A1 (en) * 1990-02-23 1991-08-28 Societe Nationale D'etude Et De Construction De Moteurs D'aviation "Snecma" Moulding device of composite material for the hot-pressing of articles from refractory material
FR2658753A1 (en) * 1990-02-23 1991-08-30 Snecma COMPOSITE MATERIAL MOLDING DEVICE FOR HOT PRESSING PARTS OF REFRACTORY MATERIAL.
AT17830U1 (en) * 2021-10-18 2023-04-15 Iag Ind Automatisierungsgesellschaft M B H Pressing tool for pressing compound mixtures

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