EP0426581B1 - Process for the lost foam casting of metal pieces under controlled pressure - Google Patents

Process for the lost foam casting of metal pieces under controlled pressure Download PDF

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Publication number
EP0426581B1
EP0426581B1 EP90420466A EP90420466A EP0426581B1 EP 0426581 B1 EP0426581 B1 EP 0426581B1 EP 90420466 A EP90420466 A EP 90420466A EP 90420466 A EP90420466 A EP 90420466A EP 0426581 B1 EP0426581 B1 EP 0426581B1
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Prior art keywords
pressure
mpa
metal
seconds
period
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EP90420466A
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German (de)
French (fr)
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EP0426581A1 (en
Inventor
Michel Garat
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Rio Tinto France SAS
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Aluminium Pechiney SA
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Priority claimed from FR898914730A external-priority patent/FR2653692B2/en
Application filed by Aluminium Pechiney SA filed Critical Aluminium Pechiney SA
Priority to AT90420466T priority Critical patent/ATE91445T1/en
Publication of EP0426581A1 publication Critical patent/EP0426581A1/en
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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22C—FOUNDRY MOULDING
    • B22C9/00—Moulds or cores; Moulding processes
    • B22C9/02—Sand moulds or like moulds for shaped castings
    • B22C9/04—Use of lost patterns
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22C—FOUNDRY MOULDING
    • B22C9/00—Moulds or cores; Moulding processes
    • B22C9/02—Sand moulds or like moulds for shaped castings
    • B22C9/04—Use of lost patterns
    • B22C9/046—Use of patterns which are eliminated by the liquid metal in the mould
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D27/00—Treating the metal in the mould while it is molten or ductile ; Pressure or vacuum casting
    • B22D27/09—Treating the metal in the mould while it is molten or ductile ; Pressure or vacuum casting by using pressure
    • B22D27/13—Treating the metal in the mould while it is molten or ductile ; Pressure or vacuum casting by using pressure making use of gas pressure
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D9/00—Machines or plants for casting ingots

Definitions

  • This technique has proven to be attractive on an industrial scale, because it avoids the prior manufacture, by compacting and agglomeration of powdery refractory materials, of rigid molds associated in a more or less complicated way with cores via channels. , and that it allows easy recovery of the molded parts as well as easy recycling of the molding materials.
  • This request teaches that after filling the mold with the molten metal, that is to say when the model has been completely destroyed by the metal, the vapors emitted by the foam have been evacuated, and preferably before the solidification of the metal begins, one exercises on the whole of the mold and metal isostatic gas pressure. This pressure is applied according to increasing values over time in order to avoid the phenomenon of watering and so that the maximum value is reached in less than 15 seconds.
  • the maximum pressure value was set between 0.5 and 1.5 MPa. But thereafter, this range was extended up to 10 MPa in the French addition certificate n ° 89-11943 deposited on September 7, 1989, in order to be able, among other improvements, to increase the resistance to fatigue of the manufactured parts .
  • the Applicant has also found that, in addition to the phenomenon of watering leading to a deformation of the part, there occurs during the combustion of the foam by the metal, a prior liquefaction of this foam followed by gasification. which generated a pressure such that gas penetrated into the metal and formed there blows while causing the appearance of carbon inclusions resulting from incomplete combustion of the foam residues.
  • the pressure growth rate is between 0.003 and 0.3 MPa / sec and the smaller the thickness of the part, the greater the overpressure being reached in less than two seconds.
  • the first period is at most two seconds since this value is most often sufficient to avoid the aforementioned drawbacks.
  • the increase in pressure build-up speed can be obtained in two different ways: - Either one proceeds in two stages during each of which a low and constant speed first then greater and constant then is applied. The pressure curve as a function of time is then represented by two straight portions with a common point located at time t ⁇ 5 seconds.
  • the pressure curve is then represented by a continuously increasing curve on which at time t ⁇ 5 seconds, the value of v is less than 0.3 MPa / sec. This can be obtained using a valve whose passage section increases gradually.
  • a collector for an internal combustion engine was made of an aluminum alloy of the A-S7U3G type containing by weight 6.9% of silicon, 3.1% of copper, 0.3% of magnesium, balance of aluminum and usual impurities .
  • This collector had thick flanges and thin fabrics 3 mm thick for which the time to reach a solidification rate of 30% was around 4 seconds; moreover, the path of the metal being long, this led to a low supply speed at the end of filling and required the metal to overheat.
  • a suspension arm was made of an aluminum alloy of the A-S7G0.3 type containing by weight 7.5% of silicon, 0.25% of magnesium, aluminum balance and its usual impurities. This arm had a normal thickness of 6 to 8 mm and the time required to reach a solidification rate of 30% was of the order of 20 seconds.

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  • Mechanical Engineering (AREA)
  • Engineering & Computer Science (AREA)
  • Mold Materials And Core Materials (AREA)
  • Casting Or Compression Moulding Of Plastics Or The Like (AREA)
  • Manufacture Of Alloys Or Alloy Compounds (AREA)
  • Molds, Cores, And Manufacturing Methods Thereof (AREA)
  • Powder Metallurgy (AREA)
  • Catalysts (AREA)
  • Forging (AREA)
  • Moulds For Moulding Plastics Or The Like (AREA)
  • Dental Prosthetics (AREA)
  • Casting Devices For Molds (AREA)
  • Heating, Cooling, Or Curing Plastics Or The Like In General (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Abstract

In the process for the lost foam casting of metal pieces under controlled pressure, the pressure is initially caused to increase at a rate of between 0.003 and 0.3 MPa/sec over a first period of at most 5 seconds from the start of the pressure rise, then at a rate greater than that of the first period over a second period until maximum pressure is reached. <??>The process makes it possible to obtain pieces with a shape corresponding to the model and without porosities.

Description

La présente invention est relative à un procédé de moulage à mousse perdue sous pression contrôlée de pièces métalliques, notamment en aluminium et en ses alliages, tel que décrit dans le brevet principal n° 2606688 (= EP-A-274 964) publié le 20 mai 1988, sur lequel le préambule de la revendication 1 est basé.The present invention relates to a process for molding lost foam under controlled pressure of metal parts, in particular aluminum and its alloys, as described in the main patent n ° 2606688 (= EP-A-274 964) published on 20 May 1988, on which the preamble of claim 1 is based.

Il est connu de l'homme de l'art, principalement par l'enseignement de l'USP n° 3 157 924, d'utiliser pour le moulage des modèles en mousse polystyrène plongés dans un moule constitué par du sable sec ne contenant aucun agent de liaison. Dans un tel procédé, le métal à mouler, qui a été préalablement fondu, est amené par l'intermédiaire de canaux traversant le sable au contact du modèle et se substitue progressivement à ce dernier en le brûlant et en le transformant en vapeurs qui s'échappent entre les grains de sable.It is known to those skilled in the art, mainly from the teaching of USP No. 3,157,924, to use for molding models of polystyrene foam immersed in a mold consisting of dry sand containing no liaison agent. In such a process, the metal to be molded, which has been previously melted, is brought through channels passing through the sand in contact with the model and gradually replaces the latter by burning it and transforming it into vapors which escape between the grains of sand.

Cette technique s'est avérée séduisante à l'échelle industrielle, parce qu'elle évite la fabrication préalable, par compactage et agglomération de matériaux réfractaires pulvérulents, de moules rigides associés de façon plus ou moins compliquée à des noyaux par l'intermédiaire de canaux, et qu'elle permet une récupération facile des pièces moulées ainsi qu'un recyclage aisé des matériaux de moulage.This technique has proven to be attractive on an industrial scale, because it avoids the prior manufacture, by compacting and agglomeration of powdery refractory materials, of rigid molds associated in a more or less complicated way with cores via channels. , and that it allows easy recovery of the molded parts as well as easy recycling of the molding materials.

Cependant, cette technique est handicapée par deux facteurs:

  • la relative lenteur de la solidification qui favorise la formation de piqûres de gazage
  • la relative faiblesse des gradients thermiques qui peut causer une microretassure si le tracé de la pièce en rend le masselottage difficile.
However, this technique is handicapped by two factors:
  • the relative slowness of solidification which promotes the formation of gassing pits
  • the relative weakness of the thermal gradients which can cause micro-back-up if the layout of the part makes its weighting difficult.

C'est dans le but d'éviter de tels inconvénients que la demanderesse a mis au point un procédé de moulage à mousse perdue, objet de la demande de brevet publiée en France sous le N° 2606688.It is with the aim of avoiding such drawbacks that the applicant has developed a lost foam molding process, the subject of the patent application published in France under No. 2606688.

Cette demande enseigne qu'après avoir rempli le moule avec le métal fondu, c'est-à-dire quand le modèle a été détruit complètement par le métal, que les vapeurs émises par la mousse ont été évacuées, et de préférence avant que la solidification du métal ne s'amorce, on exerce sur l'ensemble du moule et du métal une pression gazeuse isostatique.
Cette pression est appliquée suivant des valeurs croissantes dans le temps afin d'éviter le phénomène d'abreuvage et de manière que la valeur maximum soit atteinte en moins de 15 secondes.This request teaches that after filling the mold with the molten metal, that is to say when the model has been completely destroyed by the metal, the vapors emitted by the foam have been evacuated, and preferably before the solidification of the metal begins, one exercises on the whole of the mold and metal isostatic gas pressure.
This pressure is applied according to increasing values over time in order to avoid the phenomenon of watering and so that the maximum value is reached in less than 15 seconds.

Dans cette demande, la valeur maximum de la pression a été fixée entre 0,5 et 1,5 MPa. Mais par la suite, cette fourchette a été étendue jusqu'à 10 MPa dans le certificat d'addition français n° 89-11943 déposé le 7 Septembre 1989, afin de pouvoir, entre autres améliorations, augmenter la tenue à la fatigue des pièces fabriquées.
Entre temps, la demanderesse a aussi constaté , qu'outre le phénomène d'abreuvage conduisant à une déformation de la pièce, il se produisait lors de la combustion de la mousse par le métal, une liquéfaction préalable de cette mousse suivie d'une gazéification qui générait une pression telle que du gaz pénétrait dans le métal et y formait des soufflures tout en provoquant l'apparition d'inclusions de carbone provenant d'une combustion incomplète des résidus de mousse.In this request, the maximum pressure value was set between 0.5 and 1.5 MPa. But thereafter, this range was extended up to 10 MPa in the French addition certificate n ° 89-11943 deposited on September 7, 1989, in order to be able, among other improvements, to increase the resistance to fatigue of the manufactured parts .
In the meantime, the Applicant has also found that, in addition to the phenomenon of watering leading to a deformation of the part, there occurs during the combustion of the foam by the metal, a prior liquefaction of this foam followed by gasification. which generated a pressure such that gas penetrated into the metal and formed there blows while causing the appearance of carbon inclusions resulting from incomplete combustion of the foam residues.

Pour parer à cette nouvelle difficulté, elle a préconisé un perfectionnement, objet de la demande de certificat d'addition déposée le 7 Mars 1989 sous le N° 89-03706 et qui consiste à accroître la pression avec une vitesse telle qu'en fonction de la granulométrie du sable, de la profondeur d'immersion du modèle, elle génère rapidement et temporairement par perte de charge à travers le sable une surpression du métal fondu par rapport au sable au niveau de leur interface, cette surpression atteignant une valeur comprise entre deux limites et décroissant ensuite à mesure que ladite pression augmente puis à maintenir ladite pression constante jusqu 'à solidification complète.To overcome this new difficulty, it recommended an improvement, subject of the request for certificate of addition filed March 7, 1989 under N ° 89-03706 and which consists in increasing the pressure with a speed such that according to the granulometry of the sand, of the depth of immersion of the model, it generates quickly and temporarily by pressure drop across the sand an overpressure of the molten metal compared to the sand at their interface, this overpressure reaching a value between two limits and then decreasing as said pressure increases then maintaining said pressure constant until complete solidification.

De préférence, la vitesse de croissance de la pression est comprise entre 0,003 et 0,3 MPa/sec et est d'autant plus petit que l'épaisseur de la pièce est grande, ladite surpression maximale étant atteinte en moins de deux secondes.Preferably, the pressure growth rate is between 0.003 and 0.3 MPa / sec and the smaller the thickness of the part, the greater the overpressure being reached in less than two seconds.

C'est dans le cadre de la demande de brevet de base et de ses perfectionnements que la demanderesse a cherché à améliorer encore son procédé. En effet, il est connu que la pression maximum doit être appliquée avant que le métal coulé ait atteint un certain degré de solidification sinon l'effet de ladite pression est très atténué. Or, on a vu également que pour éviter le phénomène d'abreuvage et de pénétration dans la pièce de gaz issus de la vaporisation de la mousse, il fallait se maintenir initialement dans une fourchette donnée de surpression. Cela suppose que pour éviter une surpression trop élevée, la pression doit être augmentée pendant les premières secondes d'application de façon modérée. Mais par ailleurs, si l'on maintient cet accroissement à la même valeur, durant toute l'application de la pression, on constate que le plus souvent l'ensemble du métal est pratiquement solidifié avant que la pression maximum soit atteinte et on limite ainsi l'efficacité du procédé.It is within the framework of the basic patent application and its improvements that the applicant has sought to further improve its process. Indeed, it is known that the maximum pressure must be applied before the cast metal has reached a certain degree of solidification otherwise the effect of said pressure is very attenuated. However, it has also been seen that in order to avoid the phenomenon of watering and penetration into the room of gases resulting from the vaporization of the foam, it was necessary to maintain initially within a given range of overpressure. This assumes that to avoid too high an overpressure, the pressure must be increased during the first seconds of application in a moderate way. But moreover, if this increase is maintained at the same value, during the entire application of the pressure, it is found that most of the time the whole of the metal is practically solidified before the maximum pressure is reached and thus limits the efficiency of the process.

C'est pourquoi la demanderesse a eu l'idée de procéder à une montée en pression en deux étapes.
D'où le procédé caractérisé en ce que l'on fait croître initialement la pression à une vitesse comprise entre 0,003 et 0,3 MPa/sec pendant une première période d'au plus cinq secondes à partir du début de la montée en pression puis à une vitesse supérieure à celle de la première période, pendant une deuxième période et ce jusqu 'à ce que la pression maximum soit atteinte.This is why the Applicant had the idea of carrying out a pressure increase in two stages.
Hence the process characterized in that the pressure is initially increased at a speed of between 0.003 and 0.3 MPa / sec for a first period of at most five seconds from the start of the pressure build-up and then at a speed higher than that of the first period, for a second period and this until the maximum pressure is reached.

Ainsi, il est possible de se maintenir dans les conditions propres à éviter l'abreuvage et les inclusions de carbone et à atteindre la pression maximum avant que le métal ne soit complètement solidifié.
De préférence, la première période est au plus de deux secondes car cette valeur suffit le plus souvent à éviter les inconvénients précités L'accroissement de vitesse de montée en pression peut être obtenu de deux manières différentes:
   - soit on procède en deux étapes au cours de chacune desquelles une vitesse faible et constante d'abord puis plus grande et constante ensuite est appliquée. La courbe de pression en fonction du temps est alors représentée par deux portions de droite avec un point commun situé au temps t ≦ 5 secondes.Thus, it is possible to maintain the conditions suitable for avoiding watering and carbon inclusions and reaching the maximum pressure before the metal is completely solidified.
Preferably, the first period is at most two seconds since this value is most often sufficient to avoid the aforementioned drawbacks. The increase in pressure build-up speed can be obtained in two different ways:
- Either one proceeds in two stages during each of which a low and constant speed first then greater and constant then is applied. The pressure curve as a function of time is then represented by two straight portions with a common point located at time t ≦ 5 seconds.

Cela peut être obtenu en placant sur le circuit de gaz une vanne ou deux vannes présentant deux sections d'ouverture différente.
   - soit à un procédé au cours duquel la vitesse croît continument. La courbe de pression est alors représentée par une courbe continument croissante sur laquelle au temps t ≦ 5 secondes, la valeur de v est inférieure à 0,3 MPa/sec. Cela peut être obtenu à l'aide d'une vanne dont la section de passage augmente progressivement.
Un exemple non limitatif de ce procédé consiste à adapter une loi d'ouverture donnant une croissance de la vitesse linéaire avec le temps de forme dP dt

Figure imgb0001
= kt ce qui conduit à une loi de pression parabolique p = 1/2 kt².This can be achieved by placing a valve or two valves on the gas circuit with two different opening sections.
- or to a process during which the speed increases continuously. The pressure curve is then represented by a continuously increasing curve on which at time t ≦ 5 seconds, the value of v is less than 0.3 MPa / sec. This can be obtained using a valve whose passage section increases gradually.
A nonlimiting example of this process consists in adapting an opening law giving a growth of the linear speed with the form time. dP dt
Figure imgb0001
 = kt which leads to a parabolic pressure law p = 1/2 kt².

L'invention peut être illustrée à l'aide des exemples d'application suivants:The invention can be illustrated with the aid of the following application examples:

EXEMPLE 1EXAMPLE 1

On a réalisé un collecteur pour moteur à combustion interne en un alliage d'aluminium du type A-S₇U₃G contenant en poids 6,9% de silicium, 3,1% de cuivre, 0,3% de magnésium, solde aluminium et impuretés habituelles. Ce collecteur présentait des brides épaisses et des toiles minces d'épaisseur 3 mm pour lesquelles le temps permettant d'atteindre un taux de solidification de 30% était de l'ordre de 4 secondes; par ailleurs, le parcours du métal étant long cela entraînait une faible vitesse d'alimentation en fin de remplissage et nécessitait une surchauffe du métal.A collector for an internal combustion engine was made of an aluminum alloy of the A-S₇U₃G type containing by weight 6.9% of silicon, 3.1% of copper, 0.3% of magnesium, balance of aluminum and usual impurities . This collector had thick flanges and thin fabrics 3 mm thick for which the time to reach a solidification rate of 30% was around 4 seconds; moreover, the path of the metal being long, this led to a low supply speed at the end of filling and required the metal to overheat.

Le métal a été coulé dans un moule contenant le modèle en polystyrène noyé dans du sable et une pression maximum de 1,5 MPa a été appliquée conformément à l'invention suivant le processus:

  • pendant les deux premières secondes, une croissance de 0,25 MPa/sec de façon à atteindre une pression de 0,5 MPa.
  • pendant les deux secondes suivantes, une croissance de 0,5 MPa/sec de façon à atteindre la pression de 1,5 MPa.
The metal was poured into a mold containing the polystyrene model embedded in sand and a maximum pressure of 1.5 MPa was applied according to the invention according to the process:
  • during the first two seconds, a growth of 0.25 MPa / sec so as to reach a pressure of 0.5 MPa.
  • for the next two seconds, a growth of 0.5 MPa / sec so as to reach the pressure of 1.5 MPa.

Ce processus a été réalisé à l'aide de deux vannes de section différente placées sur le circuit d'alimentation en gaz.This process was carried out using two valves of different section placed on the gas supply circuit.

On a ainsi éviter le problème de l'abreuvage et l'inclusion de carbone dans la pièce tout en se plaçant dans des conditions telles que la pression maximum soit atteinte avant que le taux de solidification n'atteigne 30%.This avoids the problem of watering and the inclusion of carbon in the part while placing itself in conditions such that the maximum pressure is reached before the solidification rate reaches 30%.

Suivant l'art antérieur, l'application d'une pression croissant dans le temps aurait conduit pour atteindre 1,5 MPa en 4 secondes à une croissance de 0,375 MPa/sec, valeur supérieure à la limite imposée dans la demande 89-03706 et qui était de 0,30 MPa/sec.According to the prior art, the application of a pressure increasing over time would have led to growth of 0.375 MPa / sec to reach 1.5 MPa in 4 seconds, a value greater than the limit imposed in application 89-03706 and which was 0.30 MPa / sec.

EXEMPLE 2EXAMPLE 2

On a réalisé un bras de suspension en un alliage d'aluminium du type A-S₇G0,3 contenant en poids 7,5% de silicium, 0,25% de magnésium, solde aluminium et ses impuretés habituelles. Ce bras présentait une épaisseur normale de 6 à 8 mm et le temps nécessaire pour atteindre un taux de solidification de 30% était de l'ordre de 20 secondes.A suspension arm was made of an aluminum alloy of the A-S₇G0.3 type containing by weight 7.5% of silicon, 0.25% of magnesium, aluminum balance and its usual impurities. This arm had a normal thickness of 6 to 8 mm and the time required to reach a solidification rate of 30% was of the order of 20 seconds.

Le métal a été coulé dans le moule et une pression maximum de 8 MPa a été appliquée conformément à l'invention suivant le processus consistant à obtenir au moyen d'une vanne pilotée, une montée en pression parabolique répondant à la formule
P = 2x10⁻² t² avec P exprimé en MPa et t en secondes ce qui est réalisé grâce à une vitesse de montée en pression dP dt

Figure imgb0002
= 4×10⁻²tThe metal was poured into the mold and a maximum pressure of 8 MPa was applied in accordance with the invention according to the process consisting in obtaining by means of a piloted valve, a rise in parabolic pressure corresponding to the formula
P = 2x10⁻² t² with P expressed in MPa and t in seconds which is achieved thanks to a pressure build-up speed dP dt
Figure imgb0002
 = 4 × 10⁻²t

Ce processus a permis:

  • pendant les deux premières secondes d'avoir une vitesse croissante n'excédant pas 0,08 MPa/sec donc largement inférieure à la limite de 0,30 MPa/sec imposée dans la demande 89-03706 afin d'éviter l'abreuvage et cependant supérieure dès l'instant t=0,075 sec à la limite inférieure de 0,003 MPa/sec assurant une bonne évacuation des résidus gazeux et liquide provenant du modèle.
  • au terme de 20 secondes disponibles d'obtenir la pression de 8 MPa requise pour que le phénomène de compaction s'exerce pleinement.
This process allowed:
  • during the first two seconds of having an increasing speed not exceeding 0.08 MPa / sec, therefore much lower than the limit of 0.30 MPa / sec imposed in application 89-03706 in order to avoid watering and yet higher at instant t = 0.075 sec to the lower limit of 0.003 MPa / sec ensuring good evacuation of gaseous and liquid residues from the model.
  • after 20 seconds available to obtain the pressure of 8 MPa required for the phenomenon of compaction to be fully exerted.

On a évité ainsi le problème de l'abreuvage et l'inclusion de carbone dans la pièce tout en se plaçant dans les conditions telles que la pression maximum soit atteinte avant que le taux de solidification atteigne 30%.The problem of watering and the inclusion of carbon in the part was thus avoided while being placed under conditions such that the maximum pressure is reached before the solidification rate reaches 30%.

Suivant l'art antérieur, l'application d'une pression croissant dans le temps aurait conduit pour atteindre 8 MPa en 20 secondes à une croissance de 0,4 MPa/sec, valeur supérieure à la limite requise pour éviter le phénomène d'abreuvage.According to the prior art, the application of an increasing pressure over time would have led to a growth of 0.4 MPa / sec to reach 8 MPa in 20 seconds, a value greater than the limit required to avoid the watering phenomenon. .

Claims (4)

  1. Process for the lost-foam casting, under controlled pressure, of metal articles, in particular of aluminium and alloys thereof, in which a pattern of organic foam of the article to be cast is immersed into a mould of which the walls are defined by a bath of dry sand containing no binder, said mould is filled with the metal in the liquid state which is gradually substituted for the foam by burning it, then there is applied to the mould and the metal, preferably before the metal begins to solidify, a quasi-isostatic gas pressure which increases over time until it reaches a constant value of between 0.5 and 10 MPa, the phase of rise in pressure generating an over-pressure in this molten metal relative to the sand of which the maximum is within the first 5 seconds of the rise, characterised in that the pressure is initially increased at a rate of between 0.003 and 0.3 MPa/sec for a first period of at most 5 seconds from the beginning of the rise in pressure then at a rate higher than that of the first period during a second period until the maximum pressure is attained.
  2. Process according to claim 1, characterised in that the first period is at most 2 seconds.
  3. Process according to claim 1, characterised in that the rate is constant during each of the two periods.
  4. Process according to claim 1, characterised in that the rate increases continuously during the two periods.
EP90420466A 1989-10-31 1990-10-29 Process for the lost foam casting of metal pieces under controlled pressure Expired - Lifetime EP0426581B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT90420466T ATE91445T1 (en) 1989-10-31 1990-10-29 PROCESS FOR FULL MOLD CASTING OF METALLIC OBJECTS UNDER CONTROLLED PRESSURE.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8914730 1989-10-31
FR898914730A FR2653692B2 (en) 1986-11-17 1989-10-31 IMPROVEMENT IN THE LOST FOAM AND CONTROLLED PRESSURE MOLDING PROCESS OF METAL PARTS.

Publications (2)

Publication Number Publication Date
EP0426581A1 EP0426581A1 (en) 1991-05-08
EP0426581B1 true EP0426581B1 (en) 1993-07-14

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US (1) US5088544A (en)
EP (1) EP0426581B1 (en)
JP (1) JPH0626750B2 (en)
KR (1) KR940002018B1 (en)
CN (1) CN1017974B (en)
AT (1) ATE91445T1 (en)
AU (1) AU627374B2 (en)
BG (1) BG93124A (en)
BR (1) BR9005428A (en)
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FR2651453B2 (en) * 1989-09-07 1994-03-25 Pechiney Aluminium IMPROVEMENT IN THE LOST FOAM AND PRESSURE MOLDING PROCESS OF METAL PARTS.
US5301739A (en) * 1992-06-30 1994-04-12 Cook Arnold J Method for casting and densification
CN1044097C (en) * 1993-09-30 1999-07-14 上海卡拿翰五金电器有限公司 Casting technology for polyphenylacetylene foaming-type vanishing die and sand box thereof
US6152218A (en) * 1998-10-19 2000-11-28 Texaco Inc. Apparatus for reducing the production of particulate material in a subterranean well
US6749006B1 (en) 2000-10-16 2004-06-15 Howmet Research Corporation Method of making investment casting molds
US6763876B1 (en) 2001-04-26 2004-07-20 Brunswick Corporation Method and apparatus for casting of metal articles using external pressure
US6883580B1 (en) 2003-01-27 2005-04-26 Brunswick Corporation Apparatus and improved method for lost foam casting of metal articles using external pressure
US7100669B1 (en) 2003-04-09 2006-09-05 Brunswick Corporation Aluminum-silicon casting alloy having refined primary silicon due to pressure
US7494554B1 (en) 2003-05-07 2009-02-24 Brunswick Corporation Method for continuous manufacturing of cast articles utilizing one or more fluidized beds for heat treating and aging purposes
US6957685B1 (en) * 2003-05-07 2005-10-25 Brunswick Corporation Method of cleaning and of heat treating lost foam castings
US11047032B2 (en) 2013-03-05 2021-06-29 Brunswick Corporation Method for solution heat treating with pressure

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US3420291A (en) * 1965-12-29 1969-01-07 Trw Inc Method for reducing metal casting porosity
DE2358719A1 (en) * 1973-11-26 1975-06-05 Dso Metalurgia Rudodobiv Vacuum/pressure quality casting prodn. - by tiltable ladle and mould in sealed chamber at vacuum followed by pressure
FR2254387B1 (en) * 1973-12-12 1978-09-29 Dso Metalurgia Rudodobiv
SU1079353A1 (en) * 1982-05-17 1984-03-15 Московский автомеханический институт Method of casting into sand-clay moulds in autoclave
FR2606688B1 (en) * 1986-11-17 1989-09-08 Pechiney Aluminium LOSS FOAM MOLDING PROCESS FOR METAL PARTS
JP2543899B2 (en) * 1987-07-30 1996-10-16 マツダ株式会社 Full-mold casting method

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YU204290A (en) 1994-06-24
DE69002218D1 (en) 1993-08-19
DK0426581T3 (en) 1993-12-13
RU1834745C (en) 1993-08-15
NO175415B (en) 1994-07-04
KR940002018B1 (en) 1994-03-14
CN1051319A (en) 1991-05-15
JPH0626750B2 (en) 1994-04-13
AU627374B2 (en) 1992-08-20
AU6561790A (en) 1991-05-09
CS520090A3 (en) 1992-01-15
EP0426581A1 (en) 1991-05-08
ES2042256T3 (en) 1993-12-01
US5088544A (en) 1992-02-18
PT95746A (en) 1992-06-30
MX171994B (en) 1993-11-26
SI9012042A (en) 1994-12-31
KR910007601A (en) 1991-05-30
NO904706D0 (en) 1990-10-30
HUT57107A (en) 1991-11-28
PL287464A1 (en) 1991-10-21
CN1017974B (en) 1992-08-26
CA2027974A1 (en) 1991-05-01
FI92807B (en) 1994-09-30
BR9005428A (en) 1991-09-17
DE69002218T2 (en) 1993-11-11
HU205289B (en) 1992-04-28
ATE91445T1 (en) 1993-07-15
IE903892A1 (en) 1991-05-08
PL165320B1 (en) 1994-12-30
YU47436B (en) 1995-03-27
FI905367A0 (en) 1990-10-30
NO175415C (en) 1994-10-12
BG93124A (en) 1993-12-24
NO904706L (en) 1991-05-02
JPH03155434A (en) 1991-07-03
FI92807C (en) 1995-01-10
HU906933D0 (en) 1991-05-28

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