Effect of GC content on properties of GC/AlN composites by hot-pressing sintering

GC/AlN composites were prepared by hot-pressing sintering in Ar atmosphere, using aluminum nitride and glassy carbon as raw material, Y₂O₃ as additives. The effects of glassy carbon content on the sintering properties, phase composition, microstructure, thermal conductivity and dielectric properties of the composites were investigated. The results show that as the content of GC increasing, the apparent porosity increases gradually, and the glassy carbon adding restrain the sintering of the composites. When the additive content of glassy carbon is 7%, the dielectric constant reached to the maximun. The dielectric loss is highest at glassy carbon additive of 3%. With the 0-11% addition of the glassy carbon, When the additive content of glassy carbon is 11%, the lowest thermal conductivity of the composites is 48.9 W/m·K.