CVD法によるTiC-SiC系複合材料の作製と評価

抄録

Composites with several compositions in TiC-SiC system were fabricated by chemical vapor deposition and several properties were measured. The CVD conditions used were, TiCl₄-SiCl₄-CH₄-H₂ system, deposition temperature of 1350°C and total gas pressure of 60Torr. The TiC-SiC composites with various compositions were fabricated by stepwise change in the Ti/(Ti+Si) ratio in the feed gas on the basis of thermodynamic calculation for the system. The obtained composites were fully dense with columnar structure perpendicular to the substrate plane and had (220) orientation on parallel there to. Thermal expansion coefficients of the TiC-SiC composites parallel to substrate ranged from 4.5 to 7.4×10^-6K^-1 and Young's Modulus perpendicular to the substrate ranged from 220 to 467GPa depending on the composition. These measured values agreed with that calculated from some rules of mixture in composite.