Method for manufacturing an anti-oxidation system for porous ceramics on the basis of SIC and Si.sub.3 N.sub.4
AssigneeW. Haldenwanger Technische Keramik GmbH & Co. KG
InventorAndreas Sonntag
Life of this patent
Estimating the term…
Abstract
The invention relates to a method of manufacturing an anti-oxidation system for porous ceramics on the basis of SiC or Si.sub.3 N.sub.4. By means of infiltration into the pore inner spaces of a sol containing at least one metal component, conversion of the sol to a gel (sol-gel process) and a subsequent high-temperature treatment, it is possible successfully to provide a crystalline anti-oxidation layer, which is resistant to temperatures of up to at least 1650.degree. C. even under cyclic temperature stresses, and reveals a heat expansion behavior adapted to the SiC or Si.sub.3 N.sub.4 over the entire temperature range used.
Claims26
A method of manufacturing an anti-oxidation system for a sintered, porous, SiC based or Si.sub.3 N.sub.4 based ceramic, comprising the steps of:
- infiltration of a sol containing at least one metal component into inner pore spaces of the sintered ceramic, wherein the sol is formed by dispersal of metal hydroxide powder and/or partly hydrated metal oxide powder in water;
- conversion of the sol to a gel;
- and
- high-temperature treatment of the ceramic in an oxidizing atmosphere.
A method of manufacturing an anti-oxidation system for a sintered, porous, SiC based or Si.sub.3 N.sub.4 based ceramic, comprising the steps of:
- forming a sol by dispersal of metal hydroxide powder and/or partly hydrated metal oxide powder in water;
- infiltration of the sol containing at least one metal component into inner pore spaces of the sintered ceramic;
- conversion of the sol to a gel;
- and
- high-temperature treatment of the ceramic in an oxidizing atmosphere, wherein the high-temperature treatment is carried out at a temperature between about 1400.degree. C. and about 1700.degree. C.
A method of manufacturing an anti-oxidation system for a sintered, porous, SiC based or Si.sub.3 N.sub.4 based ceramic, comprising the steps of:
- infiltration of a sol containing at least one metal component into inner pore spaces of the sintered ceramic, wherein the sol is formed by dispersal of metal hydroxide powder and/or partly hydrated metal oxide powder in water, wherein the sol is introduced into the inner pore spaces by a vacuum or a pressure infiltration method;
- conversion of the sol to a gel;
- and
- high-temperature treatment of the ceramic in an oxidizing atmosphere, wherein the high-temperature treatment is carried out at a temperature of about 1400.degree. C. or higher.
Dependencies are inferred from the claim text.