| 摘要 |
A ceramic composite includes (a) 30 to 60% by volume of C-fibers; (b) 10 to 55% by volume of a matrix made of SiC and C, wherein the weight ratio SiC:C is in the range of between 20:1 and 2:1; (c) 5 to 40% by volume porosity that may be open or closed. A base material is formed from a)+b)+c). The ceramic composite also includes a protective system comprising at least one of (d) a lower protective layer that is situated directly on the base material consisting of one or more compounds comprising Si, C, B, O2 and having a thickness between 20 and 150 mum; (e) a central protective layer that is situated above the lower protective layer consisting of at least one of transition metal borides and transition metal silicides in combination with SiC, SiO2 or SiOC, and having a thickness of from 50 to 250 mum; and (f) an upper protective layer that is situated above the central protective layer consisting of one or more compounds comprising SiC, SiO2, MoSi2, Mo3Si, Mo5Si3, ZrB, ZrB2, ZrB12, Si3N4, ZrO2, Y2O3, Al2O3, mixed oxides Al2O3-SiO2, and SiOC and having a thickness of from 20 to 250 mum.
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