Application of reactive chemical vapour deposition (RCVD) for surface modification of carbon fibers
Anita Olszówka-Myalska, Lucjan Swadźba, Agnieszka Botor-Probierz, Tomasz Janus
Quarterly No. 1, 2009 pages 19-23
DOI:
keywords: carbon fibers, nanocoatings, titanium carbide, hafnium carbide, RCVD, metal matrix composite
abstract The method of reactive chemical vapour deposition (RCVD) was used for surface modification of carbon fibers FT 300B roving. Titanium carbide TiC and hafnium carbide HfC coatings were obtained in reactors with controlled reactive atmo-sphere. The TiC carbide was formed by the reaction between carbon and TiCl4. The parameters applicated during the deposi-tion in hydrogen atmosphere were as follows: temperature of 1020°C, time range of 5-30 min. The titanium carbide coatings with thickness 100-300 nm were uniform and good adherent to the fibers. The bridging effect was not observed and XRD patterns showed the presence of crystalline TiC. During formation of hafnium carbide layer the HfF4 reacted with carbon fibers in argon atmosphere at the temperature of 1050°C. Similarly to TiC coatings SEM investigations showed that HfC coating was uniform and good adherent to the fibers. The thickness on the level of 100 nm was estimated and bridging effect was not observed also. Two crystalline phases were identified by XRD method. The hafnium carbide HfC as the main one and hafnium oxide HfO2 additionally. Results of presented experiments revealed that the reactive diffusion can be useable during surface modification of carbon fibers by carbides. The effect of bridging (typical for coating deposition by such method as CVD and electrochemical and chemical electroless deposition) is excluded. Coatings obtained by RCVD are uniform, good adherent and their thickness can be controlled on the nanometric level. The experiments of coated carbon fibers with different liquid alloys are necessary for verification their potential application in metal matrix composites