METHOD OF SILICONISING THERMOSTRUCTURAL COMPOSITE MATERIALS AND PARTS THUS PRODUCED

摘要

The invention relates to a method of siliconising thermostructural composite materials and to the parts thus produced. According to the invention, an aerogel or xerogel, constituting a precursor of refractory material, is formed within the porosity of the thermostructural porous composite material. The aforementioned precursor is transformed by means of pyrolysis in order to produce an aerogel or xenogel of refractory material and, subsequently, siliconisation is performed by means of impregnation with a silicon melt-type phase. The aerogel or xerogel is formed by impregnating the composite material with a composition containing at least one organic, organometalloid or organometallic compound in solution, followed by an in situ gelling step. The inventive method can be used to improve the tribiological properties or the thermal conductivity of C/C or C/SiC composite parts or to seal such parts.