Method of protecting products of composite material against oxidizing and products protected thereby

A method of protecting a composite material product against oxidation by means of at least one refractory ceramic and a healing composition, comprising the following steps:

• forming a coating on the product of composite material to be protected, said coating comprising a mixture of a non-oxide refractory ceramic consisting of particles smaller than fifty microns, at least one refractory oxide consisting of particles smaller than fifty microns and providing healing properties by forming a glass, and a binder comprising a polymer that is a precursor to a non-oxide refractory ceramic;
• cross-linking said polymer that is a precursor to a non-oxide ceramic;
• transforming said polymer into ceramic so as to obtain a first protective layer comprising a non-oxide refractory ceramic phase and a healing phase together having a structure comprising two completely commingled networks;
• and
• forming a second protective layer, on said first protective layer, of a composition comprising a mixture of alumina and silica phosphates.

A method of protecting a composite material product against oxidation by means of at least one refractory ceramic and a healing composition, comprising the following steps:

• forming an first protective layer on the surface of said composite material product, said first protective layer comprising a vitreous coating including silica with an intermediate coating interposed between the vitreous coating and the surface of said composite material product, said intermediate coating being made of alumina or of a precursor of alumina;
• forming a coating on said composite material product, said coating comprising a mixture of a non-oxide refractory ceramic consisting of particles smaller than fifty microns, at least one refractory oxide consisting of particles smaller than fifty microns and providing healing properties by forming a glass, and a binder comprising a polymer that is a precursor to a non-oxide refractory ceramic;
• cross-linking said polymer that is a precursor to a non-oxide ceramic;
• and
• transforming said polymer into ceramic so as to obtain a second protective layer comprising a non-oxide refractory ceramic phase and a healing phase together having a structure comprising two completely commingled networks.

A method of protecting a composite material product against oxidation by means of at least one refractory ceramic and a healing composition, wherein the method comprises the following steps:

• forming an first protective layer on the surface of said composite material product, said first protective layer comprising a vitreous coating including silica with an intermediate coating interposed between the vitreous coating and the surface of said composite material product, said intermediate coating being made of alumina or of a precursor of alumina;
• forming a coating on said composite material product, said coating comprising a mixture of a non-oxide refractory ceramic consisting of particles smaller than fifty microns, at least one refractory oxide consisting of particles smaller than fifty microns and providing healing properties by forming a glass, and a binder comprising a polymer that is a precursor to a non-oxide refractory ceramic;
• cross-linking said polymer that is a precursor to a non-oxide ceramic;
• transforming said polymer into ceramic so as to obtain a second protective layer comprising a non-oxide refractory ceramic phase and a healing phase together having a structure comprising two completely commingled networks;
• and
• forming a third protective layer, on said second protective layer, of a composition comprising a mixture of alumina and silica phosphates.