Patent ID: 7011888

Claim:
A process for protecting fiber-reinforced, carbon-containing composites whose matrix comprises silicon carbide (SiC) at least in the outer layer against oxidation, which comprises the following steps: a) impregnating the composite with an aqueous, phosphate-containing solution, b) after drying, carrying out a heat treatment at a temperature which is at least sufficient to convert the dried solution into insoluble compounds which are suitable for forming a self-healing glass, c) oxydatively treating the composite at a temperature in excess of 480° C. whereby silicon in the matrix is reacted to silicon dioxide, and d) forming a silicate glass by reaction of the silicon dioxide with the material of the phosphation layer, wherein the oxidation protection is generated on a fiber-reinforced, carbon-containing composite material whose matrix comprises, at least in the outer layer, silicon (Si) and/or silicon alloys in addition to silicon carbide (SiC).