Abstract: A method of smoothing the surface of a ceramic matrix composite material part that presents a surface that is undulating and rough. The method includes depositing a refractory vitreous coating on the surface of the part, the vitreous coating essentially containing silica, alumina, baryte, and lime.

Abstract: A method of smoothing the surface of a ceramic matrix composite part presenting a surface that is undulating and rough. The method includes forming a ceramic coating on the surface of the part, the coating being made by applying a liquid composition on the surface of the part, the composition containing a ceramic-precursor polymer and a factory solid filler, curing the polymer, and transforming the cured polymer into ceramic by heat treatment. The method further includes impregnating the ceramic coating with a liquid metallic composition.

Abstract: A method of smoothing the surface of a ceramic matrix composite material part that presents a surface that is undulating and rough. The method includes depositing a refractory vitreous coating on the surface of the part, the vitreous coating essentially containing silica, alumina, baryte, and lime.

Abstract: A method of smoothing the surface of a ceramic matrix composite material part that presents a surface that is undulating and rough. The method includes depositing a refractory vitreous coating on the surface of the part, the vitreous coating essentially containing silica, alumina, baryte, and lime.

Abstract: A method of smoothing the surface of a ceramic matrix composite material part that presents a surface that is undulating and rough. The method includes depositing a refractory vitreous coating on the surface of the part, the vitreous coating essentially containing silica, alumina, baryte, and lime.

Abstract: A method of smoothing the surface of a ceramic matrix composite part presenting a surface that is undulating and rough. The method includes forming a ceramic coating on the surface of the part, the coating being made by applying a liquid composition on the surface of the part, the composition containing a ceramic-precursor polymer and a factory solid filler, curing the polymer, and transforming the cured polymer into ceramic by heat treatment. The method further includes impregnating the ceramic coating with a liquid metallic composition.

Abstract: A support slug (2) used for the heat treatment of a part (3), particularly for the hardening of a steel part, comprises a guide element (221) that is used to guide the part (3) towards a supporting surface (230) of the support slug (2) when said part is being positioned on the support slug. A ceramic element (23) including the supporting surface (230) is embedded in the metal body (20) of the support slug.

Abstract: A support slug (2) used for the heat treatment of a part (3), particularly for the hardening of a steel part, characterised by the fact that it comprises a guide element (221) that is used to guide the part (3) towards a supporting surface (230) of the support slug (2) when said part is being positioned on the support slug. The supporting surface (230) is characterised by a ceramic element (23) embedded in the metal body (20) of the support slug.

Abstract: A method of manufacturing a sintered silicon carbide ceramic part in which is formed a mixture of carbide powder with a sintering additive based on boron, beryllium or aluminium, and an injection moulding additive comprising a mixture of polystyrene and a wax. A moulded part is manufactured by injection moulding and is then baked and is finally sintered.Polystyrene is used simultaneously as a moulding agent and as a carbonizable substance. When the moulded part is baked it is heated in air to a temperature between 230.degree. C. and 330.degree. C. and is then kept at that temperature for a fairly long time to remove the wax and to reticulate and oxidize the polystyrene.Application to manufacturing dense sintered parts.

Abstract: A silicon nitride material is obtained by natural sintering in the presence of a small quantity of yttrium oxide. The method comprises the steps of mixing silicon powder with relatively small quantities of aluminum powder and yttrium oxide powder, nitriding the mixture of powders, re-crushing the nitrided mixture of powders, shaping the re-crushed powders, and then sintering the shaped re-crushed powders.