Thermal properties of field‐assisted‐sintered SiCN–Y ₂ O ₃ composites

Polymer-derived amorphous SiCN has excellent high-temperature stability and properties. To reduce the shrinkage during pyrolysis to improve oxidation resistance, Y2O3 was added as a filler. In this study, polymer-derived SiCN–Y2O3 composites were fabricated by mixing polymeric precursor of with submicron powders in different ratios. The mixtures cross-linked pyrolyzed argon. processed using field-assisted sintering technology at 1350°C for 5 min under vacuum. Dense composite pellets successfully made relative density higher than 98% homogeneous microstructure. Due low temperature short time heat-treatment, grain growth substantially inhibited. size ∼1 μm after sintering. composites’ heat capacity, thermal diffusivity, expansion coefficients characterized function temperature. conductivity ceramics decreased amount increased coefficient (CTE) content. However, CTE did not follow rule mixture. This is likely due partial resultant impurity phases such Y2SiO5, Y2Si2O7, Y4.67(SiO4)3O.