| 摘要 |
Method of improving humidity resistance in a coated article ( 19 ) comprising a carbon-carbon composite component ( 10 ), a graphite component ( 10 ), or a ceramic matrix composite component based on carbon fibers and/or graphite ( 10 ). The component ( 10 ) is preferably configured as an aircraft landing system brake disc. The method includes the steps of: (A) providing a carbon-carbon composite component ( 10 ), a graphite component ( 10 ), or a ceramic matrix composite component based on carbon fibers and/or graphite ( 10 ); (B) covering the component ( 10 ) with a phosphorus-containing antioxidant undercoating ( 11 ) having a thickness of approximately 1-10 mil; and (C) covering the resulting undercoated component ( 10, 11 ) with a boron-containing glass overcoating ( 12 ) having a thickness of approximately 1-10 mil. The overcoating includes 20-50 wt-% alkali or alkaline earth metal silicates, 3-25 wt-% alkali metal hydroxide, up to 10 wt-% boron nitride, and one or both of 5-40 wt-% elemental boron and 5-40 wt-% boron carbide. The overcoating is substantially free of phosphoric acid and phosphates. Also, articles coated with the specified undercoating/overcoating combinations.
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