Oxidation Protection Systems for Carbon-Carbon Composites Formed by Chemical Vapor Deposition and Plasma Assisted Chemical Vapor Deposition Techniques.

摘要

A final report written in three sections. (1) 'CVI Densification of Carbon-Carbon Composites' deals with the densification of porous preforms of carbonized carbon-resin mixtures using various methane and hydrogen gas mixtures. The experimental conditions include temperatures between 1000 deg C and 1200 deg C and total pressures between 5 and 15 torr. The resulting solid was characterized using optical and electron microscopy. (2) 'Oxidation Protection of Carbon-Carbon Composites Using Pack Cementation' deals with formation of oxidation protective films formed from combinations of boron carbide, silicon carbide and zirconium carbide. Films were processed using a reactive process called pack cementation. The effects of initial powder composition and temperature were correlated with microstructure and oxidation resistance. (3) In 'The Formation of Oxidation Protective Coatings on Carbon-Carbon Composites Using a Chemical Vapor Deposition (CVD) Technique four types of CVD coatings were investigated: SiC, ZrB ZrB /SiC multilayer and graded SrC/ZrC. Coatings were produced as a function of temperature, pressure and gas flow rates. The resulting coatings were then characterized in terms of microstructure and oxidation resistance. OXIDATION RESISTANCE, CHEMICAL VAPOR DEPOSITION, CARBON-CARBON.