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WO1999058269A1 - Procede de production d'un article fritte - Google Patents

Procede de production d'un article fritte Download PDF

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Publication number
WO1999058269A1
WO1999058269A1 PCT/DK1999/000249 DK9900249W WO9958269A1 WO 1999058269 A1 WO1999058269 A1 WO 1999058269A1 DK 9900249 W DK9900249 W DK 9900249W WO 9958269 A1 WO9958269 A1 WO 9958269A1
Authority
WO
WIPO (PCT)
Prior art keywords
water glass
article
particles
water
process according
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.)
Ceased
Application number
PCT/DK1999/000249
Other languages
English (en)
Inventor
Ole Huusmann
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.)
DTI Industri
Original Assignee
DTI Industri
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 DTI Industri filed Critical DTI Industri
Priority to EP99917804A priority Critical patent/EP1085953A1/fr
Priority to AU35955/99A priority patent/AU3595599A/en
Publication of WO1999058269A1 publication Critical patent/WO1999058269A1/fr
Priority to NO20005644A priority patent/NO20005644L/no
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22C—FOUNDRY MOULDING
    • B22C9/00—Moulds or cores; Moulding processes
    • B22C9/10—Cores; Manufacture or installation of cores
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22C—FOUNDRY MOULDING
    • B22C1/00—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds
    • B22C1/16—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds characterised by the use of binding agents; Mixtures of binding agents
    • B22C1/18—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds characterised by the use of binding agents; Mixtures of binding agents of inorganic agents
    • B22C1/186—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds characterised by the use of binding agents; Mixtures of binding agents of inorganic agents contaming ammonium or metal silicates, silica sols
    • B22C1/188—Alkali metal silicates

Definitions

  • the present invention relates to a process for preparing a sintered article. Furthermore, the inven- tion concerns such articles as well as the use of same as a core or a mould for iron and metal moulding or cast moulding.
  • Articles containing particles adhered together by a binder are used within many technical fields of application. Especially when casting iron or plastic objects, such articles have been used as moulds or cores. Usually, particles of quartz sand and binders of water glass are used.
  • PCT/DK97/00575 have sufficient strength for many purposes.
  • the articles are excellent for moulds or cores for metal casting.
  • JP 4325473 it is suggested to use an aqueous solution of water glass as casting and sintering aid when preparing a porous sintered article based on alumina powder. After simply mixing aqueous water glass and alumina powder, an article is dry cast and subsequently sintered. It is suggested to use the sintered porous article as a filter. Thus, it is impossible to work a green article before the sintering. Therefore, it is the object of the present inven- tion to provide a process for the preparation of a sintered article having a high degree of details and processable before the sintering. A further object of the invention is to provide a process for the prepara- tion of an article having enhanced strength and improved resistance to water or steam.
  • the sintering temperature is defined as the temperature at which the surface of the particles with no layer of water glass would start melting so that a melting together of the adjacent particles is obtained.
  • a temperature at least 10 °C above the sintering temperature is used.
  • a temperature at least 10°C above the sintering temperature is assumed to facilitate the penetration of the melted metal into the water glass layer, thus enabling the sintering of the surface of adjacent particles.
  • water glass is to be understood as lithium, sodium or potassium silicates.
  • the ratio Si0 2 /M Thread0 is designated the weight module.
  • a water glass having a low weight module is easily soluble in water and strongly basic due to a high content of the basic component MLO.
  • a water glass having a high weight module is less basic and less water soluble.
  • M Na .
  • the particles to be covered with a layer of water glass may be any material to which water glass can adhere and that can be sintered.
  • metallic materials and ceramics examples of such materials are metallic materials and ceramics.
  • usable metallic materials are aluminium, copper, tin, iron, wolfram, chrome, vanadium, molybdenum and manganese.
  • ceramics are SiC> 2 , l 2 0 3 , Fe 3 0 4 , Fe 2 C> 3 , MnO, NiO, ZnO, Zr0 2 or TiOpen .
  • the material of the particles may be a mixture of two or more of the above .
  • the size and size distribution of the particles is not essential when preparing the covered particles.
  • particles having a size between 0.05 mm and 2.0 mm, especially between 0.10 and 0.60 mm, are often used.
  • particles having a diameter of 1 to 100 ⁇ m may be used.
  • the selected particles may have a broad or narrow particle size distribution or the particle mass may consist of so- called double-sieved particles (double-sieved sand) showing two peaks on the grain size curve.
  • the article to be sintered may have been in- filtrated beforehand. It is particularly preferred that the article has been infiltrated with water glass and/or a metal or metal alloy prior to the sintering. Said infiltration may also take place after the sintering.
  • the water glass is chosen with a view to ensure the desired solubility. Water glass having a maximum weight module of appr. 3 may be dissolved immediately by water contact at ambient temperature within a foreseeable time frame, whereas water glass having a weight module above approximately 3.0, e.g. a weight module between 3.0 and 3.5, is sparingly soluble in cold water.
  • a durable article that does not dissolve or disintegrate at high air humidity is desired, possibly combined with a temperature above normal ambient temperature. Therefore, a water glass having a weight module between 3 and 4, especially between 3.0 and 3.5, is often chosen.
  • articles relatively easily soluble in water are infiltrated with a water glass having a weight module of 1.8 to 3.0.
  • metal or metal alloy may be randomly chosen from among known metals or metal alloys. It is preferred to use copper or a cupriferous alloy for the infiltration of the article according to the invention. Especially, it is preferred to use a bronze, e.g. containing appr. 90% by weight copper and appr. 10% by weight tin. Examples of applicable metals to be used either alone or combined as alloys are aluminium, antimony, bismuth, cadmium, calcium, cobalt, copper, gold, iron, lead, magnesium, manganese, mercury, nickel, silver, thallium, tin and zinc .
  • the article prepared according to the invention may have any outer shape.
  • articles may be prepared as casts of original models having a very detailed surface.
  • the article according to the invention may be a positive or a negative cast of a model.
  • a negative cast may be used as a mould for preparing a copy of the original model, whereas the positive cast per se represents a complete or partial cast of the original model .
  • the article according to the invention When used for iron or metal casting or for die- casting of plastics, the article according to the invention may constitute a mould and/or a core.
  • the article according to the invention is applicable for other purposes as well, such as catalysts or carriers thereof, granulate filters, spark electrodes, electrodes for electrolysis etc.
  • the particles covered with a layer of water glass are preferably prepared by
  • (a) depends on several factors, such as the specific surface, the porosity and the electrostatic nature of the particles, but, preferably, calculated on the basis of the weight of the particles to be covered, it is at least 0.1% by weight. Typically, an amount of 1-3% by weight is chosen to ensure adequate humidity of the particles. Preferably, the amount of water does not exceed 5% by weight since a higher water supply does not contribute further to the humidity of the surface of the particles to be covered.
  • the amount of water glass in the mixture comprising particles to be covered, water and water glass depends on factors such as the desired thickness of the layer and the specific surface of the particles to be covered. On the basis of the weight of the particles, 0.1-5% by weight water glass may be used. Generally, it is preferred to use 1-3% by weight.
  • the mixture of step (a) is preferably obtained by (al) mixing water and particles to be covered,
  • step (a3) the water glass is mainly added to the mixture in a solid form as it is preferred to use particulate solid water glass prepared by spray drying. It is expedient to keep stirring during the entire preparation of the particles covered with a layer of water glass. Said stirring is made mechanically, mainly using rotating blades. The stirring speed is adjusted so as to ensure that no cured lumps of particles are formed, which would have to be subsequently crushed.
  • the stirring is mainly performed so vigorously that the mixture is heated and the water thus evaporated.
  • the evaporation rate may be increased by supplying heat from an external source and/or evaporation may take place in vacuum.
  • the par- tides used may be preheated before being mixed with water and water glass. Said procedure is particularly advantageous if the water glass is sparingly soluble, i.e. has a weight module between 3.0 and 4.0, in which case the particles may preferably be heated to a temperature not exceeding 100°C, preferably 80-90°C, before being mixed with water and water glass.
  • said flowability is obtained both as a result of the layer of water glass being smooth and hard and because the particles ' covered interact during the drying so that the covered particles obtained are rounder than the uncovered particles.
  • a green articles may be prepared by (c) providing the particles covered with water glass in a mould, (d) ensuring the presence of water for the activation of water glass in the particle mass, and (e) curing the particles covered with water glass in the mould into a green article by supplying energy from a source thereof .
  • the particles covered with water glass may be provided in the mould in an arbitrary way.
  • loose particles are teemed into a mould, and the mould is afterwards being slightly vibrated to ensure teeming of all mould cavities in order to obtain a tight and homogenous stuffing. Such a vibration will make the small particles move towards the surface of the particle mass and thus increase the density of the surface of the green article.
  • an after-vibration at a suitable pressure may be carried out, e.g. using a plumb, to enhance a tighter particle stuffing.
  • the particles covered with water glass are provided in the mould by being blown into same by means of an airflow.
  • the airflow escapes though mould valves, and the particles will be stuffed in the mould under the influence of the pressure of the airflow.
  • the particles covered with water glass are provided in the mould by being extruded into same by a process designated "impact moulding".
  • impact moulding the particles are pounded into the mould under the influence of a high pressure, e.g. obtained by suddenly released pressure air.
  • slightly humid particles covered with a layer of water glass are provided in a mould, whereby it is ensured that the covered articles fill out all cavities of the mould, e.g. by pounding the particle mass or vibrating the mould containing the particle mass as described earlier.
  • Said process entails the advantage that the amount of water necessary for the activation is already present in the particle mass.
  • the presence of water in the particle mass and the supplying of energy from a source thereof will activate the water glass so that a coherent green article is formed. Therefore, the presence of water for the activation of the water glass in the particle mass must be ensured.
  • Said water may for instance be present in the form of crystallization water, it may be added as water vapour or the particles used may be humidified by a small quantity of water prior to the teeming of the mould, e.g. by 0.1 to 0.7% by weight water, preferably appr. 0.3% by weight.
  • the energy source for the curing may for instance be a source of microwaves or high- frequency waves, hot air, convection heat or steam.
  • vapour is conveyed through the dry particles covered with water glass provided in a mould to activate the water glass layer. Subsequently, pressure air at a temperature of 160- 200°C is added to cause a further heating of the covered particles and an initial evaporation of the water. Then the temperature is lowered to 80-160°C to remove the water from the green article prepared.
  • a pressure air temperature of 0-80°C may be used at last to cool the green article and the mould.
  • a pressure air temperature of 0-80°C may be used at last to cool the green article and the mould.
  • particles covered with water glass humidified with water are used instead of vapour humidified particles.
  • the pressure of the pressure air and the duration of the various temperature periods vary, dependent on the amount of water used for humidification, the size of the green article, the amount of used water glass etc., and said time periods may be determined by the person skilled in the art by routine tests.
  • the typical duration periods of the various temperatures would be: 10 sec of pressure air at a temperature of 160-200°C, 30 sec at a temperature of 80-160°C and 20 sec at ambient temperature.
  • the particles covered with water glass are cured by means of micro- waves or high-frequency waves.
  • the water necessary to activate the water glass may be present as crystallization water in the water glass layer, it may be added by using humid particles having a water content of for instance 0.1-0.7% by weight or be provided by conveying water vapour. As far as the latter option is concerned, it has turned out to be possible to obtain curing of an article by placing a mould containing particles covered with water glass in a microwave oven, whereby the mould inlet is facing a moist blotting paper.
  • a third preferred embodiment relates to the use of 12 moulds receiving heat by convection, e.g.
  • the moulds by placing the moulds in an oven, placing the moulds on a heating plate, or a mould with a heating jacket may be used.
  • an oven having air circulation is mainly used in order to ensure a more homogenous distribution of the heat and thus a more homogeneous curing of the green article.
  • the oven is mainly heated to a temperature of 130-200°C. The duration of the heat-treatment in the oven depends on the size and wall thickness of the green article.
  • a green article as a cast of a model, making the size of the cast larger or smaller than the surface of the model by means of adjusting the temperature of the model. Said property is particularly advantageous if the model to be copied is a spare part from which an oversize cast is desired. It has turned out that a green article produced from metal particles covered with water glass is not conductive, which is an indication of the completeness of the layers around the particles. Contrary hereto, the article is susceptible to microwave energy. Before the green article is sintered, if desired, 13 it may be worked so as to achieve the desired shape and surface quality.
  • the article After the sintering of a green article prepared from metal particles, the article is conductive and insusceptible to microwave energy. This indicates that, unexpectedly, the metal melting from the surface of the metal particles is penetrating the layer of water glass .
  • Heating to sintering the green article usually takes place in two or more temperature steps to avoid too much internal stress of the article due to the temperature difference between the surface and the inner article. Alternatively, the heating may take place continuously. Too much internal stress of the article may result in crack formation. Therefore, it is appropriate to preheat the green article in order to obtain a so high core temperature that the green article does not crack and, subsequently, raise the temperature to or above the sintering temperature.
  • the duration of the preheating step inter alia depends on the wall thickness of the article and the particles chosen and can be determined by a person skilled in the art after appropriate routine tests.
  • the duration of the sintering period depends on many parameters, e.g. how much the temperature is raised above the sintering temperature and to which degree contact is desired between the particles.
  • the temperature and the duration of the sintering may be determined by a person skilled in the art after appro- priate routine tests.
  • the heating and sintering is mainly carried out in an inert or reducing atmosphere to prevent a possible oxidizing effect of the oxygen in the air.
  • the green article may be infiltrated before, during or after the sintering to increase the strength 14 or improve the surface texture.
  • the green article Before or after the sintering, the green article may be infiltrated by a process comprising the following steps contacting the green article or the sintered article with a solution of water glass so that part of the solution is absorbed therein, heat-treating the green article or the sintered article, wherein a solution of water glass has been absorbed so that the water glass is solid- ified, and, optionally, repeating the preceding steps in order to obtain an infiltrated article.
  • the solution of water glass is usually aqueous, which makes it less detrimental to health, but other organic or inorganic solvents, in which water glass is soluble, are applicable. Since the solvent of the solution is to be removed in the subsequent step, a solution having a relatively high content of water glass is preferred. A solution having water glass and water in the weight ratio 1:2 has turned out to be suitable.
  • the water glass may have a high or a low weight module. In case a low water solubility of the article is to be obtained, water glass having a weight between 3.0 and 4.0, particularly 3.0 to 3.5, has turned out to be appropriate.
  • the green article or the sintered article may be contacted with a solution of water glass in any suitable manner.
  • the solution may be applied by spraying or brushing, or the article may be sub- merged into the solution.
  • the green article or the sintered article may be infiltrated in part or totally with the solution of water glass.
  • the solution of water glass will penetrate into the outer layer of the green article so that a reinforced shell is obtained 15 around the article.
  • all air is displaced from the article and replaced by the solution of water glass so that an article is obtained in which the entire article is reinforced.
  • the penetration depth may be controlled, e.g. by adjusting the submersion time of the green article in the solution of water glass.
  • the article may be submerged in the solution of water glass for 1-20 seconds, preferably 2- 10 sec. In case a longer submersion time of the article in the solution of water glass is desired, it is advisable that the water glass layer around the particles consists of water glass that is sparingly soluble in the solvent so that disintegration is prevented.
  • the green article or the sintered article, in which a solution of water glass has been absorbed, may be heat-treated in any suitable manner ensuring the solidification of the water glass in the green article.
  • the solvent evaporates and the water glass remains in the article and supports the article structure.
  • possibly present crystallization water may be released as well.
  • the heat treatment is usually carried out at a temperature of 100 to 250°C, preferably at a temperature of 120 to 180°C.
  • the temperature to be chosen for the heat treatment depends on the water glass used since water glass having various weight modules may comprise crystallization water that is being released at various temperatures. It may be desirable to carry out the heat treatment at a higher temperature than mentioned above in order to release possibly present crystallization water.
  • a further strength enhancement may be obtained by mixing the solution of water glass for the infiltration with a metal powder having a diameter smaller than the pore diameter of the green article.
  • an article having a non-porous surface may be obtained by carrying out an infiltration of the sintered article with water glass according to the process described above, poss- ibly repeated one or more times.
  • the surface of the sintered and infiltrated article is smooth and non- porous and may thus advantageously be used as a mould, e.g. for injection moulding.
  • the green article or the sintered article is infiltrated with a metal or a metal alloy.
  • the article is infiltrated by contacting the green article or the sintered article with a melted metal or a melted metal alloy so that melted metal or metal alloy is absorbed in the article, cooling the article comprising melted metal or metal alloy with a view to precipitate the metal or the metal alloy, and, possibly, - repeating the preceding steps in order to obtain 17 an infiltrated article.
  • the green article or the sintered article is infiltrated by being placed in an oven in physical contact with the metal in a solid form. It is preferred to use a briquette comprising pressed metal powder.
  • the heat treatment in the oven usually consists of two steps, whereby, in the first step, the oven is preheated to a temperature below the melting point of the metal for infiltration to ensure the core temperature of the article being sufficiently high. In a second step, heating continues until the melting point of the metal or the metal alloy has been reached, whereby the metal will flow into the pores of the green article or the infiltrated article.
  • the duration of the first and the second step inter alia depends on the wall thickness .
  • the green article or the sintered article substantially have the same temperature as the melting temperature of the metal or the metal alloy, or, during the infiltration, a higher temperature. Accordingly, the metal or the metal alloy infiltrate the green article completely so that the total strength of the porous structure of the green article is enhanced. If only penetration of the outer layers of the green article is desired, the core temperature of the green article may be kept lower than the melting temperature of the metal or the metal alloy for infiltration.
  • water glass softens when heated to the melting point of many metals or the metal alloys for infiltration.
  • water glass has a softening point at 640°C in case of a weight module of 3.
  • the actual melting point of water glass is above the melting point or the 18 sintering temperature of most relevant metals or metal alloys. Therefore, to obtain a successful result it is usually a necessary prerequisite for the filtration to choose a metal or a metal alloy having a melting point below the melting point of the water glass covering the particles .
  • a surplus of infiltrating metal or metal alloy is preferably used to ensure the complete infiltration.
  • excessive metal/metal alloy is usually removed from the article.
  • the green article may be infiltrated with metal or metal alloy by any prior art method known to the person skilled in the art, e.g. as described in Metals Handbook, 9 edition, volume 7, pages 551-566.
  • the material for infiltration and for particles covered with water glass may be chosen so as to obtain simultaneous sintering and infiltration of the article so that one heating process is spared.
  • Period 1 0-30 min after the admixture of water glass, the mixture was heated by the mechanical energy of the stirrer and water was allowed to freely evapor- ate;
  • Period 2 30-45 min after the admixture of water glass, the water evaporation was so advanced that the water glass began to grow sticky and a tendency towards formation of loose agglomerates was noticed. Towards the end of the time interval, the stickiness of the mixture decreased again as the amount of water in the mixture had been reduced to a point lower than the lowest bonding level and the agglomerates were broken by the stirring. At the end of the period, the water content of the mixture amounted to appr. 0.7% by weight .
  • the product obtained was examined in a microscope and showed an even and smooth layer of water glass, which was assumed to be the reason for the easy flow- ability.
  • a sintered article containing particles of iron The water glass covered iron particles obtained in Example 1, Test No. 1, were teemed into a mould that was vibrated.
  • the mould was cylindrical and having a diameter of 50 mm and a height of 50 mm.
  • the mould teemed with water glass covered particles was placed in an oven at 150°C for 40 min. Subsequently, the mould was removed from the oven and cooled to ambient temperature and the cured article taken out .
  • the cured article containing the covered particles was then placed in a sintering oven which had been preheated to 700°C in a reducing atmosphere of hydrogen.
  • the sintering oven was of the continuous type.
  • the article was kept at said temperature for 20 min in the reducing atmosphere of hydrogen.
  • the green article was conveyed to a zone having a temperature of 1,120°C and kept at same for 20 min.
  • the sintered article obtained was cooled to 100°C in the course of 30 min.
  • the weight of the obtained sintered article amounted to 344 g. 21
  • the water glass covered particles of bronze obtained in Example 1, Test No. 2, were teemed into a mould that was vibrated.
  • the mould was cylindrical having a diameter of 50 mm and a height of 42 mm.
  • the mould teemed with the water glass covered particles was placed in an oven at 150°C for 40 min. Subsequently, the mould was taken out and cooled to ambient temperature and the cured article removed from the mould.
  • the cured article containing the covered particles was then placed in a batch oven that had been preheated to 750°C in an inert atmosphere of nitrogen.
  • the article was kept at said temperature for 30 min. Subsequently, the temperature was raised to 810°C in the course of 10 min, and said temperature was maintained for 15 min, which resulted in a sintering.
  • the sintered article was cooled to ambient tem- perature in the course of 30 min.
  • the weight of the obtained sintered article amounted to 380 g.
  • the water glass covered particles of tool steel obtained in Example 1, Test No. 3, were teemed into a 22 mould that was vibrated.
  • the mould was cylindrical having a diameter of 50 mm and a height of 42 mm.
  • the mould teemed with water glass covered particles was placed in an oven at 150°C for 40 min. Subsequently, the mould was taken out and cooled to ambient temperature and the cured article removed from the mould.
  • the cured article containing the covered particles was then placed in a sintering oven that had been preheated to 300°C in a reducing atmosphere of hydrogen.
  • the sintering oven was of the continuous type.
  • the article was kept at said temperature for 30 min in the reducing atmosphere of hydrogen in order to liquate possibly present crystallization water.
  • the article was conveyed to a zone having a temperature of 700°C, which temperature was maintained for 30 min.
  • the article was led to a zone having a temperature of 1,120°C, which temperature was maintained for 30 min.
  • the sintered article was then cooled to ambient temperature in the course of 30 min.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Materials Engineering (AREA)
  • Powder Metallurgy (AREA)

Abstract

Cette invention a trait à un procédé de production d'articles frittés à partir de particules enrobées d'une couche de verre soluble. On fait adhérer des particules adjacentes de l'article par contact physique direct obtenu par chauffage à une température égale ou supérieure à la température de frittage des particules. Ce frittage confère à l'article une force de résistance accrue ainsi qu'une meilleure résistance à l'eau ou à la vapeur.
PCT/DK1999/000249 1998-05-11 1999-05-05 Procede de production d'un article fritte Ceased WO1999058269A1 (fr)

Priority Applications (3)

Application Number Priority Date Filing Date Title
EP99917804A EP1085953A1 (fr) 1998-05-11 1999-05-05 Procede de production d'un article fritte
AU35955/99A AU3595599A (en) 1998-05-11 1999-05-05 A process for preparing a sintered article
NO20005644A NO20005644L (no) 1998-05-11 2000-11-08 Fremgangsmåte for å fremstille en sintret gjenstand

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DK64098A DK173647B1 (da) 1998-05-11 1998-05-11 Fremgangsmåde til fremstilling af et sintret emne, et sådant sintret emne og anvendelse af emnet
DK0640/98 1998-05-11

Publications (1)

Publication Number Publication Date
WO1999058269A1 true WO1999058269A1 (fr) 1999-11-18

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Application Number Title Priority Date Filing Date
PCT/DK1999/000249 Ceased WO1999058269A1 (fr) 1998-05-11 1999-05-05 Procede de production d'un article fritte

Country Status (5)

Country Link
EP (1) EP1085953A1 (fr)
AU (1) AU3595599A (fr)
DK (1) DK173647B1 (fr)
NO (1) NO20005644L (fr)
WO (1) WO1999058269A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2010025861A1 (fr) * 2008-09-05 2010-03-11 Minelco Gmbh Sable à noyaux ou sable de fonderie mélangé à verre soluble et/ou enduit de verre soluble avec une teneur en eau de l'ordre d'environ 0,25 % en poids à environ 0,9 % en poids

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5211127A (en) * 1975-07-18 1977-01-27 Masao Yoshizawa Method of making core
JPS52102825A (en) * 1976-02-26 1977-08-29 Otsuka Akira Self harden molding composition
JPS5234250B2 (fr) * 1974-02-04 1977-09-02
JPS5380326A (en) * 1976-12-25 1978-07-15 Toyota Motor Co Ltd Preparation of disintegrable core
US4314399A (en) * 1976-01-28 1982-02-09 Severinsson Lars M Method of producing moulds
US5127461A (en) * 1989-10-31 1992-07-07 Ube Industries, Ltd. Water soluble cores, process for producing them and process for die casting metal using them
JPH0663683A (ja) * 1992-08-18 1994-03-08 Mitsubishi Heavy Ind Ltd 鋳型の製造方法

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5234250B2 (fr) * 1974-02-04 1977-09-02
JPS5211127A (en) * 1975-07-18 1977-01-27 Masao Yoshizawa Method of making core
US4314399A (en) * 1976-01-28 1982-02-09 Severinsson Lars M Method of producing moulds
JPS52102825A (en) * 1976-02-26 1977-08-29 Otsuka Akira Self harden molding composition
JPS5380326A (en) * 1976-12-25 1978-07-15 Toyota Motor Co Ltd Preparation of disintegrable core
US5127461A (en) * 1989-10-31 1992-07-07 Ube Industries, Ltd. Water soluble cores, process for producing them and process for die casting metal using them
JPH0663683A (ja) * 1992-08-18 1994-03-08 Mitsubishi Heavy Ind Ltd 鋳型の製造方法

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DATABASE WPI Week 7739, Derwent World Patents Index; AN 1977-69982Y, XP000858643 *
DATABASE WPI Week 7741, Derwent World Patents Index; AN 1977-73155Y, XP000858642 *
DATABASE WPI Week 7833, Derwent World Patents Index; AN 1978-59748A, XP000858648 *
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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2010025861A1 (fr) * 2008-09-05 2010-03-11 Minelco Gmbh Sable à noyaux ou sable de fonderie mélangé à verre soluble et/ou enduit de verre soluble avec une teneur en eau de l'ordre d'environ 0,25 % en poids à environ 0,9 % en poids
EP2163328A1 (fr) * 2008-09-05 2010-03-17 Minelco GmbH Sable de noyau ou de moule revêtu par et/ou mélangés avec des silicates de potassium ayant une teneur en eau comprise entre environ 0,25 poids -% jusqu'à environ 0,9 poids -%
JP2012501850A (ja) * 2008-09-05 2012-01-26 ミネルコ ゲーエムベーハー 中子砂又は鋳物砂、中子砂又は鋳物砂の製造方法、鋳型部品の製造方法、鋳型部品、中子砂又は鋳物砂の使用方法、及び中子製造具
US8627877B2 (en) 2008-09-05 2014-01-14 Minelco Gmbh Core or foundry sand coated and/or mixed with water glass with a water content in the range of ≧ approximately 0.25% by weight to approximately 0.9% by weight

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AU3595599A (en) 1999-11-29
NO20005644L (no) 2001-01-11
EP1085953A1 (fr) 2001-03-28
NO20005644D0 (no) 2000-11-08
DK173647B1 (da) 2001-05-21

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