摘要:
A gas electrode includes a plurality of stacked layers (2, 3, 4), wherein the first layer (2) is in contact with a solid substrate (1) while the last layer (4) has a free outer surface to be contacted with a gas, each layer being made of at least one mixed oxide selected from the group including perovskites and Ruddlesden-Popper phases, the micro-structure of the first layer (2) being different from that of the last layer (4), the porosity of the different layers (2, 3, 4) increasing from the first layer (2) towards the last layer (4), and the different layers stacked on each other defining a network of a solid interconnected material between the free outer surface of the last layer (4) and the solid substrate with a total thickness higher than 1 μm. A method for making such an electrode and its use in an electrochemical cell are disclosed.
摘要:
The present invention relates to a method for manufacturing a metal-oxide-based ceramic, including, in order, the step of inserting, into a flash sintering device, a nanocrystalline powder comprising crystallites and crystallite agglomerates of a ceramic of formula, Zr1-xMxO2, where M is chosen from yttrium, scandium and cerium, or Ce1-xM′xO2, where M′ is chosen from gadolinium, scandium, samarium and yttrium, where x lies between 0 and 0.2, the powder having an average crystallite size of between 5 and 50 nm, an average crystallite agglomerate size of between 0.5 and 20 μm, and a specific surface area of between 20 and 100 m2/g. The invention further includes the step of flash sintering the powder by applying a pressure of between 50 and 150 MPa, at a temperature of between 850° C. and 1400° C., for a time of between 5 and 30 minutes.
摘要:
The present invention relates to a method for manufacturing a metal-oxide-based ceramic, including, in order, the step of inserting, into a flash sintering device, a nanocrystalline powder comprising crystallites and crystallite agglomerates of a ceramic of formula, Zr1-xMxO2, where M is chosen from yttrium, scandium and cerium, or Ce1-xM′xO2, where M′ is chosen from gadolinium, scandium, samarium and yttrium, where x lies between 0 and 0.2, the powder having an average crystallite size of between 5 and 50 nm, an average crystallite agglomerate size of between 0.5 and 20 μm, and a specific surface area of between 20 and 100 m2/g. The invention further includes the step of flash sintering the powder by applying a pressure of between 50 and 150 MPa, at a temperature of between 850° C. and 1400° C., for a time of between 5 and 30 minutes.
摘要:
Method of preparing a metal oxide layer on a substrate, in which the following successive steps are carried out: a) a metal oxide powder is dispersed in a liquid medium comprising a dispersion solvent and a dispersant, the said liquid medium containing neither plasticizer nor binder, by means of which a suspension A of the said metal oxide powder in the said liquid medium is obtained; b) a solution of at least one polymer in a solvent is added to the said suspension A, by means of which a suspension B is obtained; c) suspension B is deposited on the substrate by a dip coating method, by means of which a green layer is obtained; d) the green layer obtained in step c) is dried; and e) the dried layer obtained in step d) is calcined.
摘要:
The invention relates to a method for manufacturing a thermal barrier protection covering a superalloy metal substrate and comprising at least one metal sublayer (13) and a ceramic layer (14) based on zirconia stabilized with yttrium having a column structure defining pores.The following steps are applied: impregnation of a portion of the pores of the ceramic layer (14) with a sol based on zirconia is achieved via a sol-gel route and this in order to form an anchoring sublayer (22), on said ceramic layer topped with said anchoring sub-layer (22), a continuous protective layer (20) based on oxide, is formed via a sol-gel route, and a heat treatment is carried out, whereby an outer protection layer is formed against the attack of the thermal barrier (11) by CMASes. Application to the protection of aeronautical protection parts.
摘要:
The invention relates to a method for manufacturing a thermal barrier protection covering a superalloy metal substrate and comprising at least one metal sublayer (13) and a ceramic layer (14) based on zirconia stabilized with yttrium having a column structure defining pores.The following steps are applied: impregnation of a portion of the pores of the ceramic layer (14) with a sol based on zirconia is achieved via a sol-gel route and this in order to form an anchoring sublayer (22), on said ceramic layer topped with said anchoring sub-layer (22), a continuous protective layer (20) based on oxide, is formed via a sol-gel route, and a heat treatment is carried out, whereby an outer protection layer is formed against the attack of the thermal barrier (11) by CMASes. Application to the protection of aeronautical protection parts.