Preparation and Properties of Multilayer Oxidation Resisting Coating for Carbon-carbon Composites

The author designed and prepared a multi layer oxidation resisting coating for C/C composites. The coating consits basically of a macerated transition layer, a ceramic phase barrier and a glassceram blockade. When the C/C composite covered with the coating is oxidized for 10 hours in air at 900 ℃, it has a weight ratio of only 0.034 g/cm 3 and a weight loss rate of 5 67×10 -5 g/cm 2. min; When it is cooled rapidly from 900 ℃ to room temperature and hearted rapidly from room temperature to 900 ℃ for 10 times in 10 hours, its weigh loss ratio is 8 41%, and no coating is peeled off. This indicates that this type of coating has good resitance to high temperature oxidation and thermal shock and can operate long in low and middle temperatare (not above 1000 ℃) atmospheres. This type of coating can be used as oxidation resisting coating of aircarft brake pieces of C/C composites, resulting in great enhance of brake piece′s service life.