A hybrid PACVD B4C/CVD Si3N4 coating for oxidation protection of composites

✍ Scribed by H.T. Tsou; W. Kowbel

• Publisher: Elsevier Science
• Year: 1995
• Tongue: English
• Weight: 347 KB
• Volume: 33
• Category: Article
• ISSN: 0008-6223
• DOI: 10.1016/0008-6223(95)00075-o

✦ Synopsis

Plasma-assisted Chemical Vapor Deposition (PACVD) B,C coating and a hybrid PACVD B,C/CVD Si,N, coating were deposited on a two-dimensional C-C substrate. Oxidation behavior of coated and uncoated C-C composites was studied using a thermogravimetric analyzer (TGA) in both the isothermal and kinetic mode. The PACVD coating provided an excellent oxidation protection of the CC substrate at temperatures up to 9OO"C, whereas the PACVD B,C/CVD Si3N4 coating provided good oxidation protection at temperatures up to 1300°C. Microstructural and chemical characterizations of coated composites were performed using EDS, FTIR, XPS, and XRD. A correlation between coating microstructure, composition and oxidation behavior is discussed.