EP2617091A1 - Poudre de grains de cermet fondu - Google Patents
Poudre de grains de cermet fonduInfo
- Publication number
- EP2617091A1 EP2617091A1 EP11764870.9A EP11764870A EP2617091A1 EP 2617091 A1 EP2617091 A1 EP 2617091A1 EP 11764870 A EP11764870 A EP 11764870A EP 2617091 A1 EP2617091 A1 EP 2617091A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- cermet
- cations
- powder
- dopant
- scandium
- 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- Withdrawn
Links
Classifications
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
- H01M4/90—Selection of catalytic material
- H01M4/9016—Oxides, hydroxides or oxygenated metallic salts
- H01M4/9025—Oxides specially used in fuel cell operating at high temperature, e.g. SOFC
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/02—Details
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C1/00—Making non-ferrous alloys
- C22C1/04—Making non-ferrous alloys by powder metallurgy
- C22C1/0433—Nickel- or cobalt-based alloys
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B02—CRUSHING, PULVERISING, OR DISINTEGRATING; PREPARATORY TREATMENT OF GRAIN FOR MILLING
- B02C—CRUSHING, PULVERISING, OR DISINTEGRATING IN GENERAL; MILLING GRAIN
- B02C19/00—Other disintegrating devices or methods
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- C—CHEMISTRY; METALLURGY
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- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
- C04B35/48—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on zirconium or hafnium oxides, zirconates, zircon or hafnates
- C04B35/482—Refractories from grain sized mixtures
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C1/00—Making non-ferrous alloys
- C22C1/04—Making non-ferrous alloys by powder metallurgy
- C22C1/05—Mixtures of metal powder with non-metallic powder
- C22C1/051—Making hard metals based on borides, carbides, nitrides, oxides or silicides; Preparation of the powder mixture used as the starting material therefor
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C29/00—Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides
- C22C29/12—Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides based on oxides
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
- H01M4/90—Selection of catalytic material
- H01M4/9041—Metals or alloys
- H01M4/905—Metals or alloys specially used in fuel cell operating at high temperature, e.g. SOFC
- H01M4/9066—Metals or alloys specially used in fuel cell operating at high temperature, e.g. SOFC of metal-ceramic composites or mixtures, e.g. cermets
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/10—Fuel cells with solid electrolytes
- H01M8/12—Fuel cells with solid electrolytes operating at high temperature, e.g. with stabilised ZrO2 electrolyte
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- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
- C04B2235/30—Constituents and secondary phases not being of a fibrous nature
- C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
- C04B2235/3217—Aluminum oxide or oxide forming salts thereof, e.g. bauxite, alpha-alumina
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- C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
- C04B2235/3224—Rare earth oxide or oxide forming salts thereof, e.g. scandium oxide
- C04B2235/3225—Yttrium oxide or oxide-forming salts thereof
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- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
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- C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
- C04B2235/3224—Rare earth oxide or oxide forming salts thereof, e.g. scandium oxide
- C04B2235/3229—Cerium oxides or oxide-forming salts thereof
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- C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
- C04B2235/3231—Refractory metal oxides, their mixed metal oxides, or oxide-forming salts thereof
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- C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
- C04B2235/3231—Refractory metal oxides, their mixed metal oxides, or oxide-forming salts thereof
- C04B2235/3244—Zirconium oxides, zirconates, hafnium oxides, hafnates, or oxide-forming salts thereof
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- C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
- C04B2235/30—Constituents and secondary phases not being of a fibrous nature
- C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
- C04B2235/3231—Refractory metal oxides, their mixed metal oxides, or oxide-forming salts thereof
- C04B2235/3244—Zirconium oxides, zirconates, hafnium oxides, hafnates, or oxide-forming salts thereof
- C04B2235/3246—Stabilised zirconias, e.g. YSZ or cerium stabilised zirconia
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- C—CHEMISTRY; METALLURGY
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- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
- C04B2235/30—Constituents and secondary phases not being of a fibrous nature
- C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
- C04B2235/327—Iron group oxides, their mixed metal oxides, or oxide-forming salts thereof
- C04B2235/3275—Cobalt oxides, cobaltates or cobaltites or oxide forming salts thereof, e.g. bismuth cobaltate, zinc cobaltite
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- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
- C04B2235/30—Constituents and secondary phases not being of a fibrous nature
- C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
- C04B2235/327—Iron group oxides, their mixed metal oxides, or oxide-forming salts thereof
- C04B2235/3279—Nickel oxides, nickalates, or oxide-forming salts thereof
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/10—Fuel cells with solid electrolytes
- H01M8/12—Fuel cells with solid electrolytes operating at high temperature, e.g. with stabilised ZrO2 electrolyte
- H01M2008/1293—Fuel cells with solid oxide electrolytes
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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
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/30—Hydrogen technology
- Y02E60/50—Fuel cells
Definitions
- the present invention relates to a melted cermet powder, in particular for making an element of a solid oxide fuel cell (SOFC), and in particular an anode of such a cell.
- SOFC solid oxide fuel cell
- the invention also relates to a melted cermet precursor powder and methods for making said melted cermet and melt precursor powders.
- FIG. 1 schematically shows in section an example of a solid oxide fuel cell (SOFC) manufactured by a hot pressing process.
- the battery 10 has first and second elementary cells, 12 and 14 respectively, separated by an interconnector layer 16.
- the first and second elementary cells being of similar structure, only the first elementary cell 12 is described.
- the first elementary cell 12 successively comprises an anode 18, an electrolyte layer 20 and a cathode 22.
- the anode 18 consists of an active anode layer 24 (in English "anode functional layer", or AFL), in contact with the electrolyte layer 20, and a support anode layer 26.
- the anode 18 is generally manufactured by a method of depositing on the support anode layer 26, an anode active layer 24, for example by screen printing (in English "screen printing”).
- the layers 24 and 26 may be precursor-based of the final anode material. Consolidation by sintering is then performed.
- Fuel cells or materials that can be used for the manufacture of fuel cells are for example described in WO2004 / 093235, EP 1 796 191, US 2007/0082254, EP 1 598 892 or EP 0 568 281.
- Porous zirconia cermets stabilized with yttrium and nickel oxide are commonly used to make the anode active layer. These cermets have in particular been studied in the article entitled “Stability of Channeled Ni-YSZ Cermets Produced from Self-assembled NiO-YSZ Directionally Solidified Eutectics", in J. Am. Ceram. Soc. - 88 (2005) - pages 3215/3217. This article describes a porous plate made of a Ni-YSZ cermet for the manufacture of a solid oxide fuel cell anode.
- This cermet has a regular lamellar eutectic structure, resulting from the laser directional fusion process ("laser floating-zone method” or "floating-zone fusion under laser heating”).
- the lamellar eutectic structure makes it possible to form parallel channels for the circulation of gas, the electronic transport and the diffusion of the oxygen ions (abbreviated and conclusion).
- This regular lamellar eutectic structure is therefore advantageous for manufacturing SOFC cell electrodes, especially in comparison with the cermet electrodes used previously and which, conventionally, are obtained by sintering yttria-zirconia powders and nickel oxide, or by sintering powders of zirconia, yttrium oxide and nickel oxide.
- this article recommends process parameters leading to the production of bars having a homogeneous lamellar eutectic structure: porous Ni or Co lamines acting as electronic conductors are supported by a lamellar skeleton of YSZ serving as ionic conductor (conclusion).
- the regular lamellar eutectic structure of the Ni-YSZ and Co-YSZ cermets is therefore described as advantageous for channeling electron conduction and ionic conduction.
- These cermets are therefore considered as very promising for making functional "layers” or substrates for "film-like” electrodes (article findings).
- the performance of SOFC batteries can change over time, particularly due to the aging of the anodes. This aging can lead to a decrease in battery life.
- An object of the invention is to meet this need.
- this object is achieved by means of a powder of melted grains, said grains, called “cermet seeds”, comprising a melted cermet
- said cermet having a eutectic structure
- said powder having a median diameter D 50 of between 0.3 ⁇ and 100 ⁇ .
- such a powder called “cermet powder” makes it possible to manufacture, by shaping and then sintering, a sintered body, and in particular an anode, suitable for SOFC fuel.
- this process makes it possible to manufacture sintered bodies of various shapes.
- the material of the melted grains of a cermet powder according to the invention has a particularly high porosity stability over time, especially in an application to SOFC cells. This advantageously results in a stability of performance of said batteries, and therefore a longer life.
- cermet powder according to the invention makes it possible to create additional porosity in this body, and to adjust this additional porosity, in particular by adjusting the particle size distribution of the powder.
- zirconium oxide, dopant, nickel and cobalt in molar percentages based on the total molar amount of zirconium oxide, dopant, nickel and cobalt, are such that
- a cermet powder according to the invention comprises more than 70%, more than 80%, more than 90%, more than 95%, more than 98%, and even substantially 100% of cermet grains, as a percentage. mass;
- a cermet powder according to the invention has an impurity content of less than 5%, preferably less than 2%, more preferably less than 1% by weight.
- Said cermet grains may also comprise one or more (to the extent that they are not incompatible) of the following optional characteristics:
- the cermet grains preferably comprise more than 80%>, more than 90%>, more than 95% o, or substantially 100% of said cermet, as a percentage by weight;
- the 100% complement is preferably constituted by impurities and nickel oxide and / or cobalt oxide, preferably in molar proportions such as: 0.250.NiO
- the cermet grains are more than 80%> greater than 90%>, greater than 95%, or even substantially 100% of their mass, of said cermet and precursor of said cermet;
- the zirconium oxide, the nickel, the cobalt and the dopant together represent more than 95% o, more than 98%>, more than 99%, or even substantially 100% of the cermet, in molar percentage;
- the 100% complement is constituted by impurities;
- composition of the cermet is such that, in molar percentages based on the total molar amount of zirconium oxide, dopant, nickel and cobalt:
- the cermet comprises less than 1% nickel, molar percentage, preferably does not contain nickel; preferably, the composition of the cermet is then such that, in molar percentages on the basis of the total molar amount of zirconium oxide, dopant, nickel and cobalt:
- composition of the cermet is such that, in molar percentages, for a total, excluding impurities, of 100%,
- the cermet has less than 1% cobalt, in molar percentage, preferably does not contain cobalt; preferably, the composition of the cermet is then such that, in molar percentages on the basis of the total molar amount of zirconium oxide, dopant, nickel and cobalt:
- composition of the cermet is such that, in molar percentages, for a total, excluding impurities, of 100%,
- the molar dopant content of zirconium oxide Zr0 2 based on the sum of zirconium cation contents and dopant cations, is greater than 14% and / or less than 25%;
- zirconium oxide ZrO 2 More than 90%, more than 95%, or even substantially 100%, by molar percentage, of zirconium oxide ZrO 2 is doped;
- zirconium oxide Zr0 2 is doped only with yttrium;
- the molar content of yttrium, based on the sum of the molar contents of zirconium and yttrium, is greater than 14%, preferably greater than 15% and / or less than 22%, preferably less than 21%, of preferably substantially equal to 16% or substantially equal to 20%>;
- Zirconium oxide Zr0 2 is doped only with scandium;
- the molar content of scandium, on the basis of the sum of the molar contents of zirconium and scandium, is greater than 14% and / or less than 22%, preferably substantially equal to 20%;
- - Zirconium oxide Zr0 2 is doped only with a mixture of scandium on the one hand and aluminum and / or cerium on the other hand;
- the molar content of scandium on the basis of the sum of the molar contents of zirconium, scandium, aluminum and cerium, is greater than 14% and / or less than 22%, preferably substantially equal to 20%;
- the molar content of aluminum on the basis of the sum of the molar contents of zirconium, scandium, aluminum and cerium is greater than 1% and / or less than 3%, preferably substantially equal to 2%;
- the molar content of cerium on the basis of the sum of the molar contents of zirconium, scandium, aluminum and cerium is greater than 0.5% and / or less than 1.5%, preferably substantially equal to 1%.
- the invention also relates to a powder of melted grains, called "cermet precursor grains", the composition of which is adapted to lead, by reduction, to cermet grains according to the invention.
- Such a powder of cermet precursor grains is called "cermet precursor powder”.
- the cermet precursor powder has an impurity content of less than 5%, preferably less than 2%, more preferably less than 0% by weight.
- the invention relates in particular to a cermet precursor powder comprising, or even constituted by, CoO-doped ZrO 2 grains, and / or NiO-doped ZrO 2 grains, said grains having a lamellar eutectic structure.
- the invention relates in particular to a powder of melted grains, said grains comprising
- nickel oxide O and / or cobalt oxide CoO nickel oxide O and / or cobalt oxide CoO, the contents of zirconium oxide, dopant, nickel oxide and cobalt oxide, in molar percentages, expressed on the basis of the total molar amount of zirconium oxide, dopant, nickel oxide and cobalt oxide, being such that
- This powder makes it possible to manufacture, by means of a reduction operation, a cermet powder according to the invention
- a cermet precursor grain according to the invention may have one or more of the following optional features:
- Said cermet precursor grains preferably comprise more than 80%, more than 90%, more than 95%, or even substantially 100% of said cermet precursor, in weight percent;
- a cermet precursor powder according to the invention comprises more than 70%, more than 80%, more than 90%, more than 95%, more than 98%, even substantially 100% of cermet precursor grains, in percentage by mass;
- composition of the cermet precursor grains is such that, in molar percentages expressed on the basis of the total molar amount of zirconium oxide, dopant, nickel oxide and cobalt oxide:
- the cermet precursor comprises less than 1%> nickel oxide, preferably does not contain nickel oxide;
- the composition of the cermet precursor grains is then such that, in molar percentages expressed on the basis of the total molar amount of zirconium oxide, dopant, nickel oxide and cobalt oxide: 0.176 ° C. Zr0 2 + dopant) ⁇ 0.333.
- composition of the precursor of cermet is such that, in molar percentages, for a total, excluding impurities, of 100%,
- the cermet precursor comprises less than 1% cobalt oxide, preferably does not contain cobalt oxide;
- the composition of the cermet precursor grains is then such that, in molar percentages expressed on the basis of the total molar amount of zirconium oxide, dopant, nickel oxide and cobalt oxide: 0.250.NiO ⁇ (Zr0 2 + dopant) ⁇ 0.428.NiO;
- composition of the precursor of cermet is such that, in molar percentages, for a total, excluding impurities, of 100%,
- NiO 70% - 80%
- the cermet precursor has the following molar composition, corresponding to the eutectic:
- the molar dopant content of zirconium oxide Zr0 2 based on the sum of zirconium cation contents and dopant cations, is greater than 14% and / or less than 25%;
- zirconium oxide Zr0 2 is doped
- Zirconium oxide Zr0 2 is preferably doped only with yttrium;
- the molar content of yttrium, based on the sum of the molar contents of zirconium and yttrium, is greater than 14%, preferably greater than 15% and / or less than 22%, preferably less than 21%, preferably substantially equal to 16% or substantially equal to 20%;
- Zirconium oxide Zr0 2 is doped only with scandium
- the molar content of scandium is greater than 14% and / or less than 22%, preferably substantially equal to 20%;
- Zirconium oxide Zr0 2 is doped only with a mixture of scandium on the one hand and aluminum and / or cerium on the other hand;
- the molar content of scandium based on the sum of the molar contents of zirconium, scandium, aluminum and cerium, is greater than 14% and / or less than
- the molar content of aluminum on the basis of the sum of the molar contents of zirconium, scandium, aluminum and cerium is greater than 1% and / or less than 3%), preferably substantially equal to 2%;
- the molar content of cerium on the basis of the sum of the molar contents of zirconium, scandium, aluminum and cerium is greater than 0.5% and / or less than 1.5%, preferably substantially equal to 1%;
- Zirconium oxide, nickel oxide, cobalt oxide and dopant together represent more than 95%, more than 98%, more than 99%, or even substantially 100% of the cermet precursor, in molar percentage .
- a seed of cermet or cermet precursor according to the invention preferably has a lamellar structure.
- the mean spacing between two lamellae may in particular be greater than 0.2 ⁇ , preferably greater than 0.3 ⁇ and / or less than 6 ⁇ , preferably less than 4 ⁇ .
- the median diameter D 50 is greater than 0.5 ⁇ , or even greater than 1 ⁇ , or even greater than 2 ⁇ and / or less than 80 microns, or even less than 50 microns, or even less than 40 ⁇ ;
- the powder has a median diameter greater than 0.5 ⁇ , or even greater than 1 ⁇ and less than 4 ⁇ .
- the powder has a median diameter greater than 10 ⁇ , or even greater than 20 microns and / or less than 80 microns, or even less than 50 microns, or even less than 40 ⁇ , or even less than 30. microns; Preferably, the median diameter is about 25 microns; The characteristics of the support anode layer of the SOFC stack are advantageously improved;
- the percentile 99.5, D 9 9 i5 also called “maximum size" of the grains of the powder, is less than 200 ⁇ , or even less than 150 ⁇ , or even less than 110 ⁇ ;
- the distribution of the form factor R of the powder is such that, the form factor of a grain being the ratio L / W between the length L and the width W of said grain:
- o less than 90% or even less than 80% of the grains of the powder have a form factor R greater than 1.5, and / or
- the cermet and / or cermet precursor grains have a regular structure without preferred general orientation
- - Cermet grains and / or cermet precursor are ground grains, that is to say resulting from an operation of grinding a molten product, for example in the form of particles or blocks. Such grinding gives a particular shape to the grains.
- the invention also relates to a manufacturing method comprising the following successive steps: a) mixture of particulate raw materials bringing
- a dopant of zirconium oxide chosen from yttrium, scandium, mixtures of scandium on the one hand and aluminum and / or cerium on the other hand, and / or one or more precursors of this dopant ,
- step c) comprising contacting the melt and / or the melt with a reducing fluid so that, after step d), the powder is a cermet powder according to the invention.
- the oven used in step b) is chosen from an induction furnace, a plasma torch, an arc furnace or a laser.
- the present invention also relates to a sintered product obtained by sintering a cermet and / or cermet precursor powder according to the invention.
- a sintered product according to the invention has a total porosity, preferably uniformly distributed, greater than 20%, preferably 25%, preferably greater than 30%.
- the cermet and / or cermet precursor powder according to the invention represents more than 80%>, more than 90%>, more than 95%, or even substantially 100% of the mass of the sintered product.
- the sintered product may be, in particular, all or part of an electrode, in particular an anode, in particular an active anode layer.
- the invention also relates to such an anode and an elementary cell of a solid oxide fuel cell comprising an electrode, in particular an anode, according to the invention, and such a fuel cell.
- Cermet is conventionally called a composite material containing both a ceramic phase and a metal phase.
- a "cermet precursor” is a material capable, under reducing conditions, of leading to a cermet according to the invention.
- a cermet precursor generally comprises a ceramic phase and a phase in a precursor of a metallic phase, that is to say able to transform into said metal phase under reducing conditions.
- a product is conventionally called "molten" when it is obtained by a process involving a melting of raw materials and solidification by cooling.
- eutectic is a structure or morphology obtained by melting a eutectic composition and then hardening the melt by cooling.
- a melting step is essential to obtain a eutectic structure.
- Obtaining a eutectic structure also requires the use of a eutectic composition.
- a eutectic composition exists only for certain combinations of oxides and, when it exists, the proportions of the oxides depend on the oxides considered. Even if two eutectic compositions have the same oxide in common, the content of the other oxide possibly making it possible to obtain an eutectic composition depends on the nature of this other oxide.
- the eutectic compositions MgO-Zr0 2 and SrO-Zr0 2 are such that MgO / Zr0 2 is different from SrO / Zr0 2 .
- a solidification rate greater than 0.1 K / s, preferably greater than 1 K / s is preferable to obtain a regular eutectic structure. Indeed, the inventors have found that a solidification rate of less than 0.1 K / s favors the sublimation of the oxide having the lowest melting point (CoO and / or NiO), this sublimation being able to generate a structure irregular eutectic or non eutectic structure.
- the irregular eutectic structure has no relation between the orientation of the two phases (FIG. 6C) and 6D)).
- the structure of a material resulting from a reduction of a cermet precursor having a eutectic structure is also referred to as the eutectic structure.
- a "dopant” is a metal cation other than the zirconium cation, integrated within the Zr0 2 crystal lattice, usually in solid solution.
- the dopant may be present as an insertion and / or substitution cation within the zirconium oxide.
- zirconium oxide Zr0 2 is said to be "doped at x% with a dopant"
- this conventionally means that, in said doped zirconium oxide, the amount of dopant is the molar percentage of dopant cations on the basis of total amount of dopant cations and zirconium cations.
- the amount of dopant is the molar percentage of dopant cations on the basis of total amount of dopant cations and zirconium cations.
- Y mol% yttrium
- (Zr0 2 + dopant) is meant the sum of the molar contents of zirconium cations and dopant.
- a precursor of Zr0 2 , CoO, NiO or dopant is a compound capable of leading to the formation of these oxides or dopant, respectively, by a process comprising a melting and then a solidification by cooling. From the oxide of zirconium doped with a dopant or with an oxide of said dopant is a particular example of a precursor of said dopant.
- grain size is meant the size of a grain conventionally given by a particle size distribution characterization performed with a laser granulometer.
- the laser granulometer used here is a Partica LA-950 from the company HORIBA.
- the percentiles or "percentiles" 50 (D 50 ) and 99.5 (D 9 9 15 ) are the grain sizes corresponding to the percentages by mass of 50% and 99.5%, respectively, on the cumulative particle size distribution curve. grain sizes of the powder, the grain sizes being ranked in ascending order. For example, 50% by weight of the grains of the powder have a size less than D 50 and 50% of the grains by mass have a size greater than D 50 . Percentiles can be determined using a particle size distribution using a laser granulometer.
- the "maximum grain size of a powder” is the 99.5 percentile (D 9 9 i 5 ) of said powder.
- the percentile 50 (D 50 ) of said powder is called the "median grain size of a powder", or "median diameter”.
- impurities is meant the inevitable constituents introduced involuntarily and necessarily with the raw materials or resulting from reactions with these constituents. Impurities are not necessary constituents, but only tolerated.
- the compounds forming part of the group of oxides, nitrides, oxynitrides, carbides, oxycarbides, carbonitrides and metallic species of sodium and other alkalis, iron, vanadium and chromium are impurities if their presence is not desired.
- Co cobalt and metallic nickel.
- the “aspect ratio” R is the ratio between the largest apparent dimension, or “length” L, and the smallest apparent dimension, or “width” W, of a grain.
- the length and width of a grain are typically measured by the following method. After taking a representative sample of the grains from the powder, these grains are partially embedded in the resin and undergo polishing capable of making possible a polished surface observation.
- the shape factor measurements are made from images of these polished surfaces, these images being acquired with an electron scanning microscope (SEM), in secondary electrons, with an acceleration voltage of 10 kV and a magnification of x100. (This represents 1 ⁇ per pixel on the SEM used). These images are of preference acquired in zones where the grains are the best separated, in order to facilitate the determination of the form factor.
- SEM electron scanning microscope
- the largest apparent dimension called length L
- W the smallest apparent dimension
- these dimensions are measured using an image processing software, such as for example VISILOG sold by the company NOESIS.
- the form factor R L / W is calculated. The powder form factor distribution can then be determined from the set of R form factor measurements made.
- zirconium oxide, dopant, nickel and cobalt contents of a cermet seed are molar percentages expressed on the basis of the total molar amount of zirconium oxide, dopant, nickel and in cobalt.
- all levels of zirconium oxide, dopant, nickel oxide and cobalt oxide of a cermet precursor grain are molar percentages expressed on the basis of the total molar amount of zirconium oxide, dopant, nickel oxide and cobalt oxide.
- FIG. 1 is a diagrammatic sectional view of a solid oxide fuel cell (SOFC) according to the invention
- FIGS. 2 to 5 represent photographs taken using a scanning electron microscope (SEM):
- cermet precursors molten eutectic structure having a Zr0 2 doped with 16 mol% of yttrium - NiO ( Figure 2) and Zr0 2 doped with 16 mol% yttria - CoO ( Figure 3), these products are the grains respectively powders of Examples 2 and 4 according to the invention; Melted cermets having a eutectic structure Zr0 2 doped with 16 mol% of yttrium-Ni (FIG. 4) and Zr0 2 doped with 16 mol% of yttrium-Co (FIG. 5), these products respectively constitute the grains of the powders examples 3 and 5 according to the invention;
- FIG. 6 represents diagrams illustrating regular eutectic morphologies
- FIGS. 7 (a) and 7 (b) show diagrams illustrating the reduction treatment used for the examples.
- the zirconium oxide doped with 16 mol% of yttrium appears gray in color and the nickel oxide NiO appears to be white in color.
- the zirconium oxide doped with 16 mol% of yttrium appears gray in color and the nickel oxide CoO appears in white color.
- the zirconium oxide doped with 16 mol% of yttrium appears gray in color
- the nickel Ni appears in white color
- the pores appear in black color.
- the zirconium oxide doped with 16 mol% of yttrium appears gray in color
- the cobalt Co appears in white color
- the pores appear in black color.
- the orientation changes in the direction of the lamellae visible in the various FIGS. 2 to 5 would be related to the changes of direction of the solidification front (eutectic growth plane).
- the invention relates to a method of general manufacture of a cermet precursor powder according to the invention or a cermet powder according to the invention, comprising the following successive stages:
- a dopant of zirconium oxide chosen from yttrium, scandium and mixtures of scandium on the one hand and aluminum and / or cerium on the other hand, and / or one or more precursors thereof; dopant,
- the raw materials being chosen so that, at the end of step d), the powder obtained is a powder of cermet grains or cermet precursor according to the invention.
- the cermet preferably has a composition such that:
- the contents being expressed as molar percentages based on the total molar amount of zirconium oxide, dopant, nickel and cobalt.
- the melted cermet precursor preferably has a composition such that:
- the feedstock can be adapted so that the process leads, at the end of step d) or e), to a cermet or cermet precursor powder according to the invention possibly having one or more of the optional features described above.
- the dopant can be added separately from the zirconium oxide in the feedstock. Doped zirconium oxide can also be added to the feedstock.
- the oxides Zr0 2 , CoO and / or NiO, their precursors, the dopants of zirconium oxide and their precursors preferably constitute, with the impurities, 100% of the starting charge.
- the impurities are such that, in molar percentages based on the oxides of the feedstock:
- step b) it is possible in particular to use an induction furnace, a plasma torch, an arc furnace or a laser.
- step b) the melting is preferably carried out under oxidizing conditions.
- the oxidizing conditions in step b) can be maintained in step c).
- the substantially perfect regularity of the eutectic structure resulting from a directional laser melting is not essential.
- a cermet or cermet precursor grain according to the invention can thus have first and second parallel plate networks, Ri and R 2 respectively, the lamellae of the first network and the second network. being oriented, at the interface I between the first and second networks, along axes A 1 and A 2 , respectively, spaced from each other by an angle ⁇ of more than 10 °, or even more than 20 °, more than 45 °, more than 60 °.
- the structure then locally has a privileged orientation (within a network of lamellae). On a larger scale, the orientation of the lamellae is variable, like the grooves of a fingerprint. This type of eutectic structure, considered as regular, does not therefore present a privileged general orientation.
- step c The good results obtained with these regular eutectic structures without preferred general orientation make it possible to envisage, in step c), to implement much simpler and more efficient manufacturing processes than a directional laser melting process (" laser floating-zone method "), even if the latter is also usable, especially under the conditions described in the aforementioned articles.
- a method other than a directional laser melting method, and in particular a method such as those described hereinafter, is implemented.
- a arc or induction furnace is used.
- Stage c) can be carried out, completely or partially, under oxidizing or reducing conditions. Under oxidizing conditions, a step e) is necessary to obtain a cermet powder according to the invention. Under reducing conditions, a step e) may advantageously be optional.
- the solidification rate determines the structure, and in particular, in the case of lamellar structure, the average spacing between two lamellae.
- Parallel lamellae can be rectilinear or curved.
- the possibility of using grain powders having a regular eutectic structure without preferred general orientation makes the cooling conditions less critical.
- the solidification rate and / or the orientation of the solidification front may be variable from one point to another of the molten product.
- the solidification rate can be adapted to produce regular eutectic structures. In particular, it may preferably be greater than 0.1 K / s, preferably greater than 1 K / s.
- the regularity of the structure is preferred, but the invention also relates to powders whose grains have an irregular eutectic structure.
- step d) the melt product from step c) is milled to facilitate the effectiveness of subsequent steps.
- the granulometry of the crushed product is adapted according to its destination.
- the grinding can be carried out in different types of grinders, such as for example an air jet mill, a roller mill.
- a roller mill will preferably be used.
- the crushed grains undergo a granulometric selection operation, for example by sieving.
- step e) the reduction leads to a transformation of at least a portion of the NiO and CoO oxides to Ni and Co, respectively.
- the precursor of cermet from step c) or d) is subjected to a reducing environment.
- a reducing fluid such as a hydrogenated gas.
- Said reducing fluid preferably comprises at least 4%, preferably at least 20%, or even at least 50% by volume of hydrogen (H 2 ).
- step e a cermet powder according to the invention is obtained.
- the invention also relates to a first particular manufacturing method comprising the steps a), b) described above as part of the general manufacturing process, and noted, for this first method, "ai)" and “bi)", respectively, and a step c) comprising the following steps:
- Ci solidification of these liquid droplets by contact with a fluid, so as to obtain molten grains of cermet precursor.
- a first particular manufacturing method may further include one or more of the optional features of the general manufacturing method listed above.
- step Ci ') and / or in step Ci ") said molten material and / or said liquid droplets being solidified can be brought into contact with an oxidizing fluid, if during these steps, neither said molten material, or said liquid droplets being solidified have been in contact with a reducing fluid, a step e) is essential to obtain a cermet product according to the invention.
- step c beads are then obtained in a cermet precursor.
- step Ci ') and / or in step ci " said molten material and / or said liquid droplets being solidified are brought into contact with a reducing fluid, preferably identical for step Ci ') and step ci ").
- a reducing fluid preferably identical for step Ci ') and step ci ".
- step e) is therefore no longer necessary to obtain cermet grains.
- the reducing fluid may comprise at least 4%>, preferably at least 20%), or even at least 50%> by volume of hydrogen (H 2 ).
- step Ci Even when a reducing fluid is used in step Ci ') and / or in step Ci "), a step e) can be envisaged to increase the amount of cermet
- the reducing fluid used in step C' and / or in step C11), preferably gaseous, may then be identical to or different from that optionally used in step e).
- Ci are substantially simultaneous, the means used for the dispersion causing a cooling of the melt, for example, the dispersion results from a blowing of gas through the melt, the temperature of said gas being adapted at the desired rate of solidification.
- the contact between the droplets and the oxidizing or reducing fluid may be of variable duration. Preferably, however, a contact is maintained between the droplets and this fluid until complete solidification of said droplets.
- the invention also relates to a second particular manufacturing method comprising the steps a) and b) described above as part of the general manufacturing process, and noted, for this second particular manufacturing method, "a 2 )" and “b 2 )", respectively, and a step c) comprising the steps of:
- This second particular manufacturing method may further include one or more of the optional features of the general manufacturing process listed above.
- a mold is used which allows rapid cooling.
- a mold capable of forming a block in the form of a plate, and preferably a mold as described in US 3,993,119.
- step c 2 ') and / or in step c 2 ") and / or in step c 2 "') and / or after step c 2 "') it is possible to put in contact with an oxidizing fluid said molten material and / or the cast material being solidified in the mold and / or the demolded block, If during these steps, neither said molten material nor the cast material being solidified in the mold, or the demolded block have been in contact with a reducing fluid, a step e) is essential to obtain a cermet product according to the invention.
- step c 2 ') and / or in step c 2 ") and / or in step c 2 "') and / or after step c 2 "') contact with a reducing fluid, directly or indirectly, of said molten material during casting or during solidification and / or the demoulded block
- the reducing fluid may comprise at least 4%, preferably at least 20%, or at least 50% by volume of hydrogen (H 2 )
- H 2 hydrogen
- step c 2 ') and / or in step c 2 ") and / or in step c 2 "') and / or after step c 2 "'), preferably gaseous, may be the same or different from that optionally used in step e).
- a step e) is generally preferable for increasing the amount of cermet, in particular during the manufacture of a solid block
- the reducing fluid used in step c 2 ') and / or in step c 2 ") and / or in step c 2 "') and / or after step c 2 "'), preferably gaseous, may then be identical or different from that optionally used in step e).
- said contact with the oxidizing fluid or the reducing fluid is initiated as soon as the molten material is poured into the mold and until the block is demolded. More preferably, maintaining said contact until complete solidification of the block.
- the rate of solidification of the melt during cooling may in particular always be less than 1000 K / s, less than 100 K / s, less than 50 K / s. a lamellar structure is sought, the solidification rate is preferably greater than 0.1 K / s, preferably greater than 1 K / s.
- step c 2 "') demolding is preferably carried out before complete solidification of the block, preferably the block is demolded as soon as it has sufficient rigidity to substantially maintain its shape. oxidizing or reducing fluid is then increased.
- the first and second particular methods are industrial processes for manufacturing large quantities of products, with good yields.
- a cermet powder according to the invention may in particular be used to manufacture a porous product according to the invention, in particular an anode and a porous anode active layer, for example by following a method comprising the following successive steps:
- the cermet powder used in step A) may in particular be manufactured according to steps a) to e) described above.
- the cermet powder according to the invention or the cermet precursor powder according to the invention comprises more than 70%, more than 80%>, more than 90%), more than 95%. %, more than 98%, or substantially 100% of cermet grains or cermet precursors according to the invention, in weight percent, the 100% complement being preferably impurities.
- the cermet powder according to the invention or the cermet precursor powder according to the invention contains, without regard to the optional dopant, less than 5%, preferably less than 1%, in weight percentage on the basis of said cermet precursor powder or cermet precursor powder, respectively, of component capable of reacting, during steps C) and / or D), with the optionally doped zirconia, and / or with nickel oxide and or with cobalt oxide, and / or with nickel and / or with cobalt, and in particular with the zirconia and / or nickel and / or cobalt of the cermet grains according to the invention, or with the zirconia and / or the nickel oxide and / or the cobalt oxide of the cermet precursor grains according to the invention.
- the cermet powder according to the invention or the cermet precursor powder according to the invention contains substantially no such constituents.
- the porous product obtained at the end of step C) or of step D) may thus comprise more than 70%, more than 80%, more than 90%, more than 95%, more than 98%. > or substantially 100% of cermet grains according to the invention, in percent by weight.
- the cermet grains according to the invention in this porous product may advantageously consist, for more than 80%>, of more than 90%>, more than 95%, or even substantially 100% of their mass, of structural material. eutectic.
- the inventors have surprisingly found that such a porous product has a particularly thermally stable porosity.
- step B) the powder can be put into any form, a deposit in the form of a layer being possible.
- step C) the shaped powder is sintered according to conventional sintering techniques, preferably by hot pressing.
- the sintering can be carried out in an oxidizing atmosphere, for example in air, if the powder is a cermet precursor powder.
- step D) the sintered powder is heat-treated in a reducing environment, which makes it possible to use, at step A), a cermet precursor powder according to the invention.
- a cermet precursor powder is used in step A) and the manufacturing method comprises a step S) of air sintering and a step D) of heat treatment in a reducing environment.
- the porous product according to the invention may have a high total porosity, typically greater than 20% and / or less than 60%. Total porosity results from intragranular porosity and intergranular porosity created during sintering.
- Comparative Example 1 The product of Comparative Example 1, in the form of a plate, was obtained by directional laser melting ("laser floating zone" in English), using a 600 power C0 2 laser. watts.
- the raw materials used are as follows:
- NiO powder having a median diameter of approximately 1 ⁇ and obtained by grinding in a microbrush with zirconia balls with a diameter of 1 mm and in 2-propanol, a powder marketed by the company Alfa Aesar, particle size -325 mesh, purity greater than 99.99%, then drying at 70 ° C for 10 hours;
- a zirconium oxide powder doped with 16 mol% of yttrium marketed by TOSOH under the name 8YSZ, with a median diameter of 0.25 ⁇ and a purity of 99.9%.
- the raw materials in powder are chosen and their quantities adapted according to the product to be manufactured.
- the raw materials are intimately mixed in acetone.
- the suspension is stirred for 1 hour.
- the suspension is then deagglomerated with ultrasound in eight cycles of 2 minutes each and then dried at 70 ° C for 12 hours.
- the mixture thus obtained is pressed in the form of a plate.
- the resulting plate is then sintered under air as follows:
- the thus sintered plate is then moved in translation (without rotation) through the beam of a laser set at 50W. It thus undergoes a floating zone melting under laser heating on its upper part, with a constant growth rate of 500 mm / h, which corresponds to a solidification rate of 100 K / s.
- a quartz tube of approximately 100 cm in length and with an internal diameter of 3 cm is introduced into a tubular oven at a standstill.
- the quartz tube is longer than the oven, in order to allow movement of the tube in the oven, according to the principle described in FIG. 7.
- a reducing gas mixture consisting of 4 vol% hydrogen (H 2 ) and 96 Nitrogen (N 2 ) is circulated in the quartz tube at a rate of 0.7 liter / minute to remove all traces of oxygen.
- the oven is then heated to 850 ° C. (rise in temperature of about 10 ° C./min)
- the previously weighed plate is then introduced into the quartz tube (Fig. 7 (a)), and the quartz tube is moved into the oven to allow the plate to be treated to be placed in the hot zone of the oven for 3.5 hours (Fig. 7 (b)). )).
- the plate thus obtained undergoes, after cooling, a grinding step of removing the part of the plate that has not been melted by the laser. After rectification, a cermet plate with a thickness of 500 ⁇ is obtained
- Example 2 The product of Example 2 according to the invention was obtained by directional laser melting ("Laser floating zone” in English), using a C0 2 laser power 600 Watts, crushed and sieved.
- the raw materials used are as follows:
- NiO powder having a median diameter of approximately 1 ⁇ and obtained by grinding, in a zirconia ball mill and in 2-propanol, a powder marketed by Alfa Aesar, of particle size distribution; 325 mesh, purity greater than 99.99%, then drying at 70 ° C for 10 hours;
- a zirconium oxide powder doped with 16 mol% of yttrium marketed by TOSOH under the name 8YSZ, with a median diameter of 0.25 ⁇ and a purity of 99.9%.
- the raw materials in powder are chosen and their quantities adapted according to the product to be manufactured.
- the raw materials are intimately mixed in acetone.
- the suspension is stirred for 1 hour.
- the suspension is then deagglomerated with ultrasound in eight cycles of 2 minutes each and then dried at 70 ° C for 12 hours.
- the mixture thus obtained is put into the form of rods by cold isostatic pressing (“CIP”) at 175 MPa for 5 minutes.
- CIP cold isostatic pressing
- the rods obtained are then sintered under air as follows:
- the rods thus sintered are then moved in translation (without rotation of the rods) through the beam of a laser set at 50W. They thus undergo a floating zone melting under laser heating, with a constant growth rate of between 10 and 3500 mm / h, which corresponds to a solidification rate of between 2 and approximately 700 K / s.
- the product of the rods is crushed and screened in order to obtain a powder of cermet precursor grains according to the invention.
- a quartz tube of approximately 100 cm in length and an internal diameter of 3 cm is introduced into a tubular oven at a standstill.
- the quartz tube is longer than the oven, in order to allow movement of the tube in the oven, according to the principle described in FIG. 7.
- a reducing gas mixture consisting of 4 vol% hydrogen (H 2 ) and 96 vol % Argon (Ar), is circulated in the quartz tube with a flow rate of 0.7 liter / minute to remove any trace of oxygen.
- the oven is then heated to 750 ° C. (rise in temperature of about 10 ° C./min)
- the previously weighed rod is then introduced into the quartz tube (Fig. 7 (a)), and the quartz tube is moved.
- the rod is then crushed and screened in order to obtain a cermet seed powder according to the invention.
- Example 4 The product of Example 4 was obtained by melting in an arc furnace.
- the raw materials used are as follows:
- a zirconium oxide powder of purity equal to 99.65%, with a median diameter of between 4 and 5 ⁇ , marketed under the name CZ-5 by Saint-Gobain Zirpro; a powder of yttrium oxide, purity greater than 99%, marketed by Treibacher Industrie AG under the name Yttrium oxide 99.99%).
- a feedstock made by the mixture of said raw materials was melted in a Herault single-phase electric arc furnace with graphite electrodes, with a graphite tank of 3 liters, a voltage of 65 to 70 V, an intensity of 400 A and a specific electrical energy supplied of 1230 kWh / T charged.
- the conditions of preparation were oxidizing.
- melting is performed, the molten liquid is cast to form a net.
- the blowing cools these droplets and congeals them in the form of melted particles of size between 0.01 and 3 mm.
- the cooling rate is a function of the size of the particle. It is about 1000 K / s for particles of size 0.3 mm. These particles are then milled using a roller mill and screened so as to obtain a powder of cermet precursor grains according to the invention.
- Example 5 The product of Example 5 was obtained by reducing the powder of Example 4 according to the protocol described below:
- Example 4 About 1 kg of powder according to Example 4 is introduced into a sintered alumina muffle of cylindrical shape 300 mm long and 100 mm in diameter, placed in a Heraeus Kl 8 electric furnace. A reducing gas mixture consisting of 10 vol% > hydrogen (H 2 ) and 90 vol%> argon (Ar), is circulated in the quartz tube with a flow rate of 3 liter / minute to remove any trace of oxygen. The oven is then heated to 1000 ° C (temperature rise of about 300 ° C / h) for a period of 12 hours. After cooling, a cermet seed powder is obtained according to the invention.
- a reducing gas mixture consisting of 10 vol% > hydrogen (H 2 ) and 90 vol%> argon (Ar)
- the oven is then heated to 1000 ° C (temperature rise of about 300 ° C / h) for a period of 12 hours. After cooling, a cermet seed powder is obtained according to the invention.
- Discs 28 mm in diameter and 2 mm thick were then made from the powder of Example 2 (powder according to the invention) by uniaxial cold pressing at a pressure of 69 MPa. The resulting discs were then hot-pressed in air at 1280 ° C, with a maximum pressure of 12 MPa applied for 30 minutes.
- the disks obtained have no visible cracks.
- the powders according to the invention thus make it possible to manufacture eutectic structure cermet parts of various shapes and having no cracks. These parts proved to be well suited to the manufacture of SOFC fuel cell anodes.
- Each rod is then subjected to the following aging treatment: a quartz tube of approximately 100 cm in length and an internal diameter of 3 cm is introduced into a tubular oven at a standstill.
- the quartz tube is longer than the oven, in order to allow displacement of the tube in the oven, according to the principle illustrated in FIG. 7.
- a reducing gas mixture consisting of 4.8 vol% hydrogen (H 2 ), 3 vol% of water (H 2 0) and 92.2 vol% of argon (Ar), is circulated in the quartz tube with a flow rate of 0.4 liter / minute in order to eliminate all traces of 'oxygen.
- the oven is then raised to 850 ° C (temperature rise of about 10 ° C / min).
- the wand is then introduced into the quartz tube, and the quartz tube is moved into the oven to allow the wand to be treated to be placed in the hot zone of the oven for 600 hours.
- the quartz tube is then moved so that the rod is out of the oven, and the latter is extracted from the tube for analysis.
- the pore number distribution prior to the aging treatment of the rod of Comparative Example 1 is the cumulative pore distribution measured on each of the five samples taken from that rod prior to the aging treatment.
- 50% by number of pores have a pore size smaller than the median diameter, D50.
- the percentage increase of the median diameter D50 is defined by the following formula:
- the measurements show a much smaller change in porosity in the example according to the invention than in the comparative example.
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FR1057339A FR2964669B1 (fr) | 2010-09-14 | 2010-09-14 | Poudre de grains de cermet fondu |
PCT/IB2011/054010 WO2012035497A1 (fr) | 2010-09-14 | 2011-09-14 | Poudre de grains de cermet fondu |
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CN109688842A (zh) * | 2016-08-08 | 2019-04-26 | 株式会社明治 | 酸性液状营养组合物 |
WO2020068435A1 (fr) * | 2018-09-24 | 2020-04-02 | Corning Incorporated | Mémoires quantiques de guide d'ondes en céramique à oxyde métallique dopé aux terres rares et leurs procédés de fabrication |
CN109663909A (zh) * | 2019-01-14 | 2019-04-23 | 常熟市华德粉末冶金有限公司 | 一种高精度粉末冶金汽车点火开关锁舌的制备方法 |
CN110429332A (zh) * | 2019-09-06 | 2019-11-08 | 深圳先进技术研究院 | 一种无机固态电解质片的制备方法 |
Family Cites Families (12)
Publication number | Priority date | Publication date | Assignee | Title |
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US3993119A (en) | 1974-11-08 | 1976-11-23 | Norton Company | Progressively or continuously cycled mold for forming and discharging a fine crystalline material |
US5141825A (en) * | 1991-07-26 | 1992-08-25 | Westinghouse Electric Corp. | Method of making a cermet fuel electrode containing an inert additive |
TW269058B (fr) | 1992-04-29 | 1996-01-21 | Westinghouse Electric Corp | |
IT1277439B1 (it) * | 1995-08-04 | 1997-11-10 | Eniricerche Spa | Cernet di nichel e relativo procedimento di preparazione |
JP4605885B2 (ja) * | 2000-10-23 | 2011-01-05 | 東邦瓦斯株式会社 | 支持膜式固体電解質型燃料電池 |
WO2004093235A1 (fr) | 2003-04-10 | 2004-10-28 | University Of Connecticut | Dispositifs electrochimiques a semi-conducteurs |
CN100483818C (zh) | 2003-08-06 | 2009-04-29 | Toto株式会社 | 固体氧化物型燃料电池 |
US20060166070A1 (en) * | 2003-09-10 | 2006-07-27 | Ion America Corporation | Solid oxide reversible fuel cell with improved electrode composition |
JP4476689B2 (ja) | 2004-05-11 | 2010-06-09 | 東邦瓦斯株式会社 | 低温作動型固体酸化物形燃料電池単セル |
AU2006201026B2 (en) | 2005-12-06 | 2008-01-10 | Council Of Scientific And Industrial Research | An improved process for the manufacture of strontium doped lanthanum manganite (LSM) ceramic powder suitable for solid oxide fuel cell (SOFC) applications |
FR2921204B1 (fr) * | 2007-09-14 | 2009-12-04 | Saint Gobain Ct Recherches | Poudre a grains allonges |
CN101771149A (zh) * | 2008-12-29 | 2010-07-07 | 中国科学院大连化学物理研究所 | 镁改性的镍基固体氧化物燃料电池复合阳极及制备和应用 |
-
2010
- 2010-09-14 FR FR1057339A patent/FR2964669B1/fr not_active Expired - Fee Related
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2011
- 2011-09-14 WO PCT/IB2011/054010 patent/WO2012035497A1/fr active Application Filing
- 2011-09-14 US US13/820,410 patent/US20130209920A1/en not_active Abandoned
- 2011-09-14 EP EP11764870.9A patent/EP2617091A1/fr not_active Withdrawn
- 2011-09-14 CN CN2011800442533A patent/CN103250293A/zh active Pending
- 2011-09-14 JP JP2013527731A patent/JP2013545884A/ja not_active Withdrawn
- 2011-09-14 KR KR1020137007591A patent/KR20130116072A/ko not_active Application Discontinuation
Also Published As
Publication number | Publication date |
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WO2012035497A1 (fr) | 2012-03-22 |
JP2013545884A (ja) | 2013-12-26 |
CN103250293A (zh) | 2013-08-14 |
US20130209920A1 (en) | 2013-08-15 |
FR2964669A1 (fr) | 2012-03-16 |
FR2964669B1 (fr) | 2012-08-31 |
KR20130116072A (ko) | 2013-10-22 |
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