| abstract |
The invention concerns: textile preforms, sheathed in a boron nitride coating; said coating (which has been produced on said pre-constituted textile preforms) having an original structure: granular microporous; composite materials structured by thermolysis, the reinforcing texture of which is constituted by said textile preforms; the respective methods for preparing the textile preforms and said composite materials structured by thermolysis. The invention is characterised in that their textile preforms, with fibre base (F), sheathed in the original interphase (I BN), embedded in the densifying matrix (M). |