Abstract: The invention relates to a composite material element (1), the composite material comprising a microfissured matrix (7) in the form of a three-dimensional interconnected network (4) of microfissures exposed on the surface of the ceramic matrix, an additive material (6) consisting of a flux or glass being dispersed in the matrix, the additive material (6) being a material which, when the composite material is brought to a predetermined temperature, softens and migrates by capillarity in the network (4) of microfissures (4) to said surface of the element. The quantity of additive material dispersed initially in the matrix is in a sufficient proportion compared to the matrix intended to coat a surface (5) of the composite material element left exposed so as to create a gas-tight barrier.

Abstract: A method for making a multilayer coating on a surface of a substrate by means of at least one thermal spraying method, wherein the following successive steps are carried out: a) a first nanostructured or finely structured layer (21) of a first material is deposited on the surface of the substrate (20) by means of a thermal spraying method via a liquid route; the surface of the substrate (20) not having been subject, prior to the deposition of the first nanostructured or finely structured layer (21), to any preparation or activation treatment other than an optional cleaning treatment; b) a second microstructured layer (22) of a second material is deposited on the first nanostructured or finely structured layer (21) by means of a thermal spraying method. The first layer obtained in step a) is an adhesion layer aiming at optimizing the adhesion of the layer obtained in step b) without any surface preparation or activation.

Abstract: Process for producing at least one nanoporous layer of nanoparticles chosen from nanoparticles of a metal oxide, nanoparticles of metal oxides, and mixtures of said nanoparticles, on a surface of a substrate, in which at least one colloidal sol, in which said nanoparticles are dispersed and stabilized, is injected into a thermal plasma jet which sprays said nanoparticles onto said surface. Nanoporous layer and device, especially a separation device, comprizing said layer.

Abstract: Process for producing at least one nanoporous layer of nanoparticles chosen from nanoparticles of a metal oxide, nanoparticles of metal oxides, and mixtures of said nanoparticles, on a surface of a substrate, in which at least one colloidal sol, in which said nanoparticles are dispersed and stabilized, is injected into a thermal plasma jet which sprays said nanoparticles onto said surface. Nanoporous layer and device, especially a separation device, comprizing said layer.

Abstract: The invention relates to a composite material element (1), the composite material comprising a microfissured matrix (7) in the form of a three-dimensional interconnected network (4) of microfissures exposed on the surface of the ceramic matrix, an additive material (6) consisting of a flux or glass being dispersed in the matrix, the additive material (6) being a material which, when the composite material is brought to a predetermined temperature, softens and migrates by capillarity in the network (4) of microfissures (4) to said surface of the element. The quantity of additive material dispersed initially in the matrix is in a sufficient proportion compared to the matrix intended to coat a surface (5) of the composite material element left exposed so as to create a gas-tight barrier.