Microstructural development during liquid phase sintering of silicon carbide ceramics

摘要: Abstract The microstructures of liquid phase sintered α-SiC ceramics have been characterised by analytical electron microscopy including energy filtered imaging. materials were fabricated with different additions Al2O3 and/or Y2O3 and densified pressureless sintering or hot isostatic pressing (HIP). Y, Al-garnet α-Al2O3 partitioned from the medium during pressure-less leaving only thin intergranular films residual glass. formation was promoted incorporation surrounding SiC Al 2 O 3 powder bed. thickness analysed Al- O-rich glassy at grain boundaries estimated to be 1.4–1.5 nm Fresnel out-of-focus crystallisation Y-, Al-, Si- liquids suppressed HIP, however, Y2Si2O7 in absence Al. applied high pressure HIP resulted a limited decomposition whereby graphite SiO2 formed.