EP2061733A2 - Procédé de fabrication d'un corps moulé en céramique, en particulier poreux, et corps moulé fabriqué avec ce procédé - Google Patents

Procédé de fabrication d'un corps moulé en céramique, en particulier poreux, et corps moulé fabriqué avec ce procédé

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Publication number
EP2061733A2
EP2061733A2 EP07800179A EP07800179A EP2061733A2 EP 2061733 A2 EP2061733 A2 EP 2061733A2 EP 07800179 A EP07800179 A EP 07800179A EP 07800179 A EP07800179 A EP 07800179A EP 2061733 A2 EP2061733 A2 EP 2061733A2
Authority
EP
European Patent Office
Prior art keywords
powder
suspension
shaped body
nitride
volume
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP07800179A
Other languages
German (de)
English (en)
Inventor
Reinhard Simon
Robert Danzer
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.)
Montanuniversitaet Leoben
Original Assignee
Montanuniversitaet Leoben
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 Montanuniversitaet Leoben filed Critical Montanuniversitaet Leoben
Publication of EP2061733A2 publication Critical patent/EP2061733A2/fr
Withdrawn legal-status Critical Current

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    • C04B38/00—Porous mortars, concrete, artificial stone or ceramic ware; Preparation thereof
    • C04B38/0051—Porous mortars, concrete, artificial stone or ceramic ware; Preparation thereof characterised by the pore size, pore shape or kind of porosity
    • C04B38/0064—Multimodal pore size distribution
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B18/00—Layered products essentially comprising ceramics, e.g. refractory products
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B82—NANOTECHNOLOGY
    • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y30/00—Nanotechnology for materials or surface science, e.g. nanocomposites
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    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
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    • Y10T442/00—Fabric [woven, knitted, or nonwoven textile or cloth, etc.]
    • Y10T442/30—Woven fabric [i.e., woven strand or strip material]

Definitions

  • the invention relates to a method for producing a particularly porous ceramic molding, which ceramic molding is optionally reinforced with fibers and / or textile semifinished such as tissue, wherein a powder A and at least one further powder B are suspended in a liquid, after which from the thus created Suspension is optionally formed in combination with fibers and / or textile semi-finished a molded body and optionally the shaped body is sintered.
  • the invention further relates to a fiber-free, in particular porous ceramic molding.
  • the invention relates to a composite body consisting of a particular porous ceramic and fibers and / or textile semifinished such as tissue.
  • Porous ceramic materials have very large in this context
  • these materials are suitable for a variety of applications, for example as catalyst supports, as filters for liquid metals or gases, as lightweight components, as bioactive implants or as reinforcement components for composites with metals or polymers.
  • porous ceramics are functionally exposed to high mechanical loads in use, it is procedurally important that they can be produced without cracks and with a homogeneous, preferably defect-free microstructure and that a uniformly distributed over the body porosity in controllable Way is adjustable. Inhomogeneities in the microstructure represent potential weak points under load and should therefore not be present.
  • a suspension can only be used to laminate fibers. It can not be used for other common processing processes such as casting or extrusion.
  • a fiber content in the solid state is therefore limited to a maximum of 48 percent by volume in order to avoid cavities and / or cracks and / or a defect-rich matrix.
  • this known method is therefore extremely time-consuming, can lead to the solidification of the suspension, can only be used for lamination processes and is only applicable for the production of laminate products with a certain fiber content.
  • the invention has the object to provide a method of the type mentioned, in which the disadvantages set out above are eliminated or at least reduced and which has a much wider application potential.
  • Another object of the invention is to provide a prepared from a plurality of powders, fiber-free, in particular porous ceramic moldings of high strength, the homogeneous microstructure with optionally uniform porosity and which is essentially free of cracks produced.
  • a still further object of the invention is to provide a highly tough composite body consisting of a particular porous ceramic and fibers and / or textile semifinished such as fabric, in which the ceramic is made of several powders, having a homogeneous microstructure with optionally uniform porosity and which in Essentially free of cracks can be produced.
  • the object of the invention to provide a method of the type mentioned above, in which the disadvantages set out above are eliminated or at least reduced, is achieved by suspending the powders A and B approximately at a pH of the liquid in a generic method, in which a viscosity minimum of the suspension is given.
  • suspensions can now also be cast or extruded, so that basically all known shaping methods can be used.
  • the pH to be maintained in the suspension of the powder can be readily determined by the skilled person in sufficient accuracy or approximation by a dilute suspension of the powder A and B with z. B. 30 volume percent solids and the viscosity of this suspension is determined depending on the pH.
  • fiber-free molded bodies can be sintered either to porous or also to substantially dense ceramics. The same applies to the ceramic matrix content in fiber-reinforced ceramics.
  • multi-phase microstructures with a homogenous microstructure can be achieved through the use of several different powders and thus materials with specifically adjusted properties can be provided.
  • a suitable surface charge can be brought about by adding an additive such as a peptizer or polyelectrolyte which is adsorbed on at least one of the powders when preparing the suspension.
  • an average grain size of the powder A is at least four times that of the powder B.
  • the powder A has an average grain size of more than 300 nm and the powder B has an average grain size of less than 100 nm. It has proven to be favorable that the powder B has a higher zeta potential in terms of magnitude.
  • Powders B is 0.65: 0.35 to 0.90: 0.10. At these volume ratios of the powder shrinkage can be minimized, which has a favorable effect on a crack-free formation of ceramic components.
  • this is preferably used when a volume fraction of the powders in the suspension is more than 50% by volume, preferably more than 55% by volume.
  • the dispersing medium or the liquid is usually water. If one of the powders used reacts with water, it is also possible to resort to other liquids which do not react with the powder (s).
  • a hardener is added to the suspension before the formation of a shaped body, which supports coagulation of the particles in the shaped body during or after formation of the shaped body.
  • the added hardener causes a Shifting of the pH to the isoelectric point and preferably forms a solid reaction product with the liquid.
  • a hardener may be a metal nitride, in particular magnesium nitride, gallium nitride, lanthanum nitride, zirconium nitride, aluminum nitride, yttrium nitride or hafnium nitride.
  • the curing agent may also be an organosilicon polymer, in particular polysilazane, polycarbosilazane, polysilazilazane or polysilylcarbodiimide.
  • organosilicon polymer in particular polysilazane, polycarbosilazane, polysilazilazane or polysilylcarbodiimide.
  • These hardeners decompose in water with elimination of pH-changing substances and thus ensure a shift of the pH towards the isoelectric point, at which the existing and then neutral composite particles unite due to van der Waals forces, so that it comes to a consolidation.
  • the curing agent can also crosslink to a polymeric solid and thus also lead to a cross-linking of the powder particles with each other, thus acting to increase strength.
  • any two- or three-dimensional semi-finished textile fiber products for. As scrims, braids, knitted or crocheted.
  • the fibers / semi-finished products can be surface-coated before and / or after infiltration with suspension with a bonding agent and thereby glued or solidified.
  • organosilicon polymers or various sols such as metal alkoxides and solutions of inorganic salts are suitable.
  • Inventive moldings can be sintered, optionally partially or completely.
  • the further object of the invention is achieved by a shaped body according to claim 16.
  • a shaped body according to the invention can be seen inter alia in a substantially crack-free structure both in the green state and in the sintered state. At the same time a low-defect or -free structure formation and optionally a uniformly distributed porosity is given.
  • a porosity can be varied depending on the powders used and a sintering temperature in a wide range, for. B. between 0.05 and 50 percent by volume. If porous shaped bodies are desired, a porosity is preferably between 30 and 45 By volume. Alternatively, shaped bodies according to the invention can also be made substantially dense by appropriate sintering guidance.
  • the shaped body advantageously has a structure in which particles of the powder A are largely enveloped by particles of the powder B and firmly bonded to them.
  • Another advantage is that a maximum size of defects in the microstructure is smaller than a maximum grain size. Such low defect sizes lead to a disproportionately high strength of the molding, with an increase in strength was observed both for green moldings and sintered moldings.
  • the volume ratio of the powder A to the powder B or the powders B is 0.65: 0.35 to 0.90: 0.10.
  • the powder A has an average grain size of more than 300 nm and the powder B has an average grain size of less than 100 nm.
  • the still further object of the invention is achieved by a composite body according to claim 20.
  • a composite body according to the invention has a high fiber content and a low-defect matrix and is therefore highly tough and also withstands load situations in which durability of the matrix is the decisive criterion.
  • Fig. 2 Cast green shaped body; 3 shows a scanning electron micrograph of composite particles in a dried green body;
  • Fig. 5 A cross section of a fiber-ceramic composite part in ⁇ 45 ° fiber orientation.
  • a sufficiently accurate determination of the viscosity minimum of a high solids suspension can be carried out by preliminarily at low solids levels, e.g. B. 15 to 30 percent by volume, a viscosity is determined depending on the pH or an amount of acid.
  • additives are proportionally suspended in a determination of a viscosity minimum with the powders.
  • a viscosity of the suspension can then be determined, for example, by means of rotational viscometry.
  • a viscosity minimum depends on the pH and can also have a ratio of fine powder ("fine”, average particle size less than 100 nanometers) to coarse powder (“coarse”, average particle size greater than 500 nanometers). vary.
  • Particle size distributions of the powders used to prepare the suspension are determined individually for each powder in the suspended state by means of electro-acoustics.
  • F denotes the maximum force
  • D the diameter of the sample and t the thickness of the sample. Cylindrical samples with a diameter of 20 mm and a thickness of 10 mm were used.
  • Example 1 (porous alumina ceramic)
  • a ceramic suspension was prepared by bringing deionized water with five molar HNO 3 solution to a pH of 4.2 to 4.5 followed by AIOOH powder having an average particle size (d 50 ) of 120 nanometers and Al 2 O. 3 powders having a mean particle size (d 50 ) of 950 nanometers were suspended. In order to maintain a constant pH in the range of a viscosity minimum, a quantity of HNO 3 solution required for this purpose was simultaneously added with the powders. The suspended powders had a zeta potential of + 65 mV (AIOOH) and + 49 mV (Al 2 O 3 ) in the region of the viscosity minimum.
  • the suspension was deagglomerated continuously during the addition of the individual components, the suspension being ground in the circulation via an agitator ball mill. In this case, a very homogeneous distribution of the powder particles was achieved in the suspension and the coarse powder particles were largely enveloped by the finer powder particles. A proportion of the finer AIOOH powder in the powder mixture was 30% by volume. A solids content in the suspension after preparation was 58% by volume. The preparation of 1.5 liters of suspension required only two hours.
  • the low-viscosity suspension had a viscosity (here as below at 20 0 C) of 200 to 400 mPas. Despite its high solids content in the suspension, this low viscosity made it possible to pour off the suspension into non-porous plastic or metal molds, whereby differently shaped green bodies were produced while maintaining very fine structural details of the negative mold. Solidification of the suspension in the casting mold took place, depending on the reaction conditions, within about one to six Hours. A few hours after pouring the green bodies were removed from the mold and then dried.
  • the green bodies were characterized in the wet state by a high strength of about 28 to 300 kPa, which made possible a problem-free demolding and handling of the green body even with very complicated geometries. Surface structures were preserved in all subtleties (see FIG. 2).
  • the green bodies had a homogeneous, largely defect-free and ordered structure. Such a structure is shown by way of example on the basis of a scanning electron micrograph in FIG. 3. In this structure, the coarse powder particles are largely enveloped by fine powder particles and firmly bonded together, resulting in a high strength of the green body.
  • Green body prepared as described were sintered in a box furnace for eight hours isothermally at a temperature of 1300 0 C in ambient atmosphere. A linear vibration on sintering was less than 1.85 volume percent.
  • the ceramics consisted of a stable ⁇ -Al 2 O 3 phase.
  • the ceramics typically had an open, interconnect porosity of about 40 volume percent and a mean pore diameter of about 250 nanometers or less. As can be seen by way of example from FIG. 4, the ceramics were characterized by an extremely homogeneous, virtually defect-free microstructure and formed substantially free of cracks.
  • the finer ZrO 2 powder was characterized by a zeta potential of + 52 mV in the region of the viscosity minimum and by a zeta potential of + 39 mV by the coarser one.
  • the particle sizes (d 50 ) were 90 nanometers and 1.2 microns, respectively, with a proportion of the finer powder in the powder mixture in the suspension being 20 percent by volume.
  • a granulate having an average diameter of about 0.8 millimeters was produced.
  • the dried granules were pre-sintered in a chamber oven for five hours isothermally at a temperature of 1200 0 C in ambient atmosphere. After this treatment, the granules had an open, interconnecting porosity and high strength.
  • the presintered granules were then added to a finely dispersed suspension containing ZrO 2 powder with a mean particle size of 90 nanometers, the suspended solids typically being 90 percent by volume granules and 10 percent more fine ZrO 2 powder.
  • a solids content in the suspension was adjusted to 58% by volume.
  • Example 2 the dried green bodies were characterized by a very homogeneous, almost defect-free and ordered microstructure, in which the coarser granulate particles were largely enveloped by the finer powder particles and firmly joined to them.
  • substantially crack-free ceramics consisted of a tetragonal ZrO 2 phase with a typically hierarchical, open, interconnective porosity of about 38 percent by volume.
  • a pore size distribution was bimodal, with a mean pore diameter of smaller pores at about 250 nanometers and a mean pore diameter larger pores at about 170 microns.
  • the powders used were strongly agglomerated or aggregated in the dry state.
  • the powders had zeta potentials of + 57 mV (SiO 2 ), + 68 mV (AIOOH) and + 42 mV (SiC) in the region of the viscosity minimum.
  • the average powder sizes were 66 nm (SiO 2 ), 59 nanometers (AIOOH) and 550 nanometers (SiC), respectively.
  • a cationic condenser eg a polyelectrolyte or a surfactant
  • positive zeta potentials can be set even with normally negatively charged particle surfaces (SiC) or with respect to the sign (positive or negative) for all powders negative) the same zeta potential is adjustable.
  • the suspension was continuously deagglomerated by pumping the suspension through a stirred ball mill.
  • a very homogeneous distribution of the powder particles was achieved in the suspension, wherein the coarse powder particles were largely enveloped by the fine powder particles or were bound to this.
  • a solids content of the suspension after preparation was 54% by volume.
  • the proportion of the fine powder in the powder mixture was typically 10 to 30% by volume.
  • AIN powder For the purpose of solidification, a small amount of AIN powder was added to the suspension. After homogenization of the suspension, this was degassed under vacuum to remove any air bubbles. At this time, the low-viscosity suspension had a viscosity of 500 to 900 mPas. By pouring the suspension into non-porous plastic or metal molds, various shaped green bodies were produced. The solidification of the suspension in the mold was carried out depending on
  • the green bodies had a strength of 23 to 260 kPa when wet.
  • the green bodies were characterized by a very homogeneous, almost defect-free and ordered structure, in which the coarse powder particles were largely enveloped by the fine powder particles and firmly bound to them.
  • a proportion of organic components (resulting from the cationic condenser) in the green body was less than 1, 2 percent by weight.
  • the green bodies thus produced were densely sintered in an oven for 3 hours isothermally at a temperature of 1600 0 C in an inert atmosphere. In the process, the fine powders formed mullite.
  • the substantially crack-free, dense ceramic was characterized by a very homogeneous, nearly defect-free microstructure with the two phases arranged such that mullite preferentially surrounded the SiC grains and formed a substantially continuous seam typically with a thickness of about 80 to 120 nanometers , This shows that the finer powders can be used for the targeted adjustment or modification of grain boundaries, which provides a control of the functional and mechanical properties of ceramics.
  • a ceramic suspension was kept in the region of the viscosity minimum of the suspension (by keeping the pH substantially constant between 3.8 to 4.2) by continuous addition of fine SiO 2 powder, fine AIOOH powder, coarse mullite powder and 5 molar HNO 3 solution to an aqueous solution of a cationic condensing agent.
  • the powders used were strongly agglomerated or aggregated in the dry state.
  • the fine SiO 2 powder was characterized in the region of the viscosity minimum by a zeta potential of + 55 mV.
  • An average particle size (d 50 ) was 65 nanometers; the fine AIOOH powder was characterized by a zeta potential of + 62 mV in the area of the minimum viscosity.
  • An average particle size (d 50 ) was 55 nanometers; the coarse mullite powder was characterized by a zeta potential of + 45 mV in the region of the minimum viscosity. An average particle size (d 50 ) was 710 nanometers.
  • the suspension was continuously deagglomerated by pumping the suspension through a stirred ball mill.
  • a very homogeneous distribution of the powder particles was achieved in the suspension, wherein the coarse powder particles were largely enveloped by the fine powder particles or the fine powder particles were bound to the coarse.
  • the solids content of the suspension after preparation was 51% by volume.
  • the proportion of the fine powder in the powder mixture was typically 10 to 30% by volume.
  • AIN powder For the purpose of solidification, a small amount of AIN powder was added to the suspension. After homogenization of the suspension, this was degassed under vacuum to remove any air bubbles. At that time, the thin liquid pointed Suspension has a viscosity of 150 to 280 mPas.
  • Simply molded composite ceramic components were prepared by individually infiltrating several layers of oxide fiber fabric (Nextel 720; 3M Ceramic Textiles and Composites, St. Paul, MN, USA) with the suspension and depositing them in a plastic or metal mold. The resulting composite molded articles were compacted by means of a vacuum bag and demolded after about 12 hours.
  • the dried laminates were characterized by a very homogeneous and ordered structure, wherein in the matrix, the coarse powder particles were largely enveloped by the fine powder particles and firmly connected with these. A proportion of organic components (resulting from the cationic condenser) in the composite was less than 1, 2 percent by weight.
  • the laminates were characterized by excellent sintering behavior and high strength.
  • the laminates thus produced were sintered in an oven for 10 hours at temperatures between 1200 to 1350 0 C in normal atmosphere.
  • the fine powder compacted almost completely in a first step and formed crystalline mullite in a second step.
  • a linear shrinkage of the matrix was less than 1.8 percent.
  • a fiber content of the ceramic was typically 52 to 55 volume percent (see FIG. 5), a porosity 17 to 20 volume percent.
  • the composite ceramic was characterized by a homogeneous microstructure with a very low residual stress state, as well as excellent mechanical properties and excellent high-temperature stability. The mechanical behavior was itself after
  • Such a composite part are a low-defect matrix state in combination with a high fiber volume fraction. This generally leads to higher mechanical characteristics, above all also in the case of matrix-dominated load situations (eg in tensile load situations). or shear stress at ⁇ 45 ° to the fiber axes), which was previously a significant weak point of such composite ceramics.
  • Example 5 (Ceramic Matrix Composite by Infusion Method) A suspension was prepared as in Example 4. The solids content in the suspension after preparation was 48% by volume. A proportion of the fine powder in the powder mixture was typically 10 to 30% by volume. For the purpose of solidification, a small amount of AIN powder was added to the suspension. After homogenization of the suspension, this was degassed under vacuum to remove any air bubbles. At this time, the very low-viscosity suspension had a viscosity of 80 to 170 mPas.
  • Carbon fiber textile preforms of 3-dimensional reinforcement architecture were placed in a mold and infiltrated with the suspension by infusion. After solidification, the laminates were demolded and sintered in an inert atmosphere at temperatures as in Example 4.
  • the composite ceramic was characterized by a homogeneous microstructure with low-defect matrix structure and 3-dimensional amplification architecture.
  • a ceramic suspension was kept in the region of the viscosity minimum of the suspension (by keeping the pH substantially constant between 4.0 to 4.4) by continuous addition of fine SiC powder, fine AIOOH powder, coarse Al 2 O 3 powder and 5 molar HNO 3 solution to produce an acidic aqueous solution of a cationic-effect condenser.
  • the powders used were strongly agglomerated or aggregated in the dry state.
  • the fine SiC powder was characterized in the range of the minimum viscosity by a zeta potential of + 50 mV (average particle size (d 50 ) of 150 nanometers).
  • the fine AIOOH powder was characterized in the area of the viscosity minimum by a zeta potential of + 65 mV (average particle size (d 50 ) of 59 nanometers).
  • the coarse Al 2 O 3 powder was in the range of Viscosity minimum characterized by a zeta potential of + 45 mV (mean particle size (d 50 ) of 350 nanometers).
  • the suspension was continuously deagglomerated by pumping the suspension through a stirred ball mill.
  • a very homogeneous distribution of the powder particles was achieved in the suspension, wherein the coarse powder particles were largely enveloped by the fine powder particles.
  • a solids content of the suspension after its preparation was 54 percent by volume.
  • a proportion of the fine powder in the powder mixture was typically 10 to 30% by volume.
  • this was degassed under vacuum to remove any air bubbles. At this time, the suspension had a viscosity of 500 to 900 mPas.
  • the suspension was extruded through a die with a small amount of polysilazane added ( ⁇ 1 volume percent) for rapid solidification of the suspension just prior to extrusion. The solidification took place depending on the reaction conditions within a few minutes to one hour.
  • the green bodies were characterized by a high strength, which made a problem-free handling possible.
  • the dried green bodies were further characterized by a very homogeneous, almost defect-free and ordered structure, in which the coarse powder particles were largely enveloped by the fine powder particles and firmly connected to these.
  • the green bodies were further characterized by excellent sintering behavior and high strength.
  • the green bodies thus produced were sintered isothermally in a furnace for 2 hours at a temperature of 1800 0 C in an inert atmosphere to a specific gravity of 99.5%.
  • This forms a nanocomposite with nanoscale inter and intra phases of SiC in an Al 2 O 3 matrix.
  • the polysilazane also formed nanoscale SiCO or SiCNO dispersoids.
  • the essentially dense ceramic was characterized by a very homogenous, almost defect-free microstructure as well as excellent strength and toughness (by microstructural reinforcement with nano-dispersoids) as well as high-temperature resistance.
  • Solidification by means of polysilazane and plastic molding processes such as extrusion can be applied.
  • the polysilazane increases the green strength compared to AIN, since not only ammonia is formed, but also a crosslinking reaction takes place.
  • the crosslinked polysilazane further contributes to the structure reinforcement during sintering by the formation of nano-dispersoids.

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Abstract

L'invention concerne un procédé de fabrication d'un corps moulé en céramique, en particulier poreux, ledit corps en céramique étant éventuellement renforcé de fibres et/ou de produits textiles semi-finis, par exemple des tissus. Une poudre A et au moins une autre poudre B sont mises en suspension dans un liquide, suite à quoi on forme un corps moulé à partir de la suspension ainsi formée et éventuellement en combinaison avec des fibres et/ou un produit textile semi-fini, le corps moulé étant éventuellement fritté. L'invention prévoit de mettre les poudres A et B en suspension sensiblement à une valeur du pH du liquide associée à un minimum de viscosité de la suspension, ce qui permet d'établir une haute teneur en solides dans la suspension tout en conservant une basse viscosité. Cela permet une fabrication rapide de corps moulés largement exempts de fissures et dont la structure est avantageusement exempte de défauts.
EP07800179A 2006-09-14 2007-09-13 Procédé de fabrication d'un corps moulé en céramique, en particulier poreux, et corps moulé fabriqué avec ce procédé Withdrawn EP2061733A2 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
AT0152906A AT504168B1 (de) 2006-09-14 2006-09-14 Verfahren zur herstellung eines insbesondere porösen keramischen formkörpers und damit hergestellter formkörper
PCT/AT2007/000434 WO2008031130A2 (fr) 2006-09-14 2007-09-13 procédé de fabrication d'un corps moulé en céramique, en particulier poreux, et corps moulé fabriqué avec ce procédé

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EP2061733A2 true EP2061733A2 (fr) 2009-05-27

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US (1) US20090325442A1 (fr)
EP (1) EP2061733A2 (fr)
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CN107879731B (zh) * 2017-11-13 2020-07-07 清华大学 一种利用水性聚氨酯增强超轻泡沫陶瓷坯体强度的方法
US20210154641A1 (en) * 2019-11-27 2021-05-27 Solenis Technologies, L.P. Sorbent for at least one metal

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US4218255A (en) * 1976-08-30 1980-08-19 University Of Dayton Porous ceramic carriers for controlled release of proteins, polypeptide hormones, and other substances within human and/or other mamillian species and method
CA1325327C (fr) * 1987-01-20 1993-12-21 Kenji Saita Procede de fabrication de produits de ceramique poreux
US4814300A (en) * 1987-12-02 1989-03-21 The Duriron Company, Inc. Porous ceramic shapes, compositions for the preparation thereof, and method for producing same
US5009822A (en) * 1989-07-17 1991-04-23 University Of Florida Alumina-or alumina/zirconia-silicon carbide whisker ceramic composites and methods of manufacture
US5188780A (en) * 1991-04-18 1993-02-23 Regents Of The University Of California Method for preparation of dense ceramic products
US5382396A (en) * 1992-06-15 1995-01-17 Industrial Technology Research Institute Method of making a porous ceramic filter
ES2088677T3 (es) * 1992-07-28 1996-08-16 Ludwig J Gauckler Procedimiento para la fabricacion de cuerpos ceramicos en bruto.
US5788891A (en) * 1994-05-09 1998-08-04 Gauckler; Ludwig J. Method for the forming of ceramic green parts
SI9500073A (en) * 1995-03-09 1996-10-31 Inst Jozef Stefan Process of modifying of ceramic products from water solution with a high contains of dry substance.
DE19943103A1 (de) * 1999-09-09 2001-03-15 Wacker Chemie Gmbh Hochgefüllte SiO2-Dispersion, Verfahren zu ihrer Herstellung und Verwendung
DE10318514B3 (de) * 2003-04-24 2004-09-16 Dornier Gmbh Mehrschichtiges keramisches Verbundmaterial mit thermischer Schutzwirkung

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See references of WO2008031130A2 *

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AT504168A1 (de) 2008-03-15
AT504168B1 (de) 2008-08-15
WO2008031130A2 (fr) 2008-03-20
WO2008031130A3 (fr) 2008-07-03
US20090325442A1 (en) 2009-12-31

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