Studies of the ceramic material produced by pressureless sintering from the AlN-Y2O3-(Si-C) powder composition using electron microscopy, Raman spectroscopy and measurements of the thermal conductivity and microwave radiation

Samples of composite with ceramic matrix of aluminum nitride have been produced by pressureless sintering of the AlN-Y2O3 powder compositions with addition of SiC-C particles of size 50 nm (agglomerates of 200 nm). The presence of a SiC solid solution in AlN has been revealed by Raman and X-ray diffraction microanalyses and measurements of microwave energy attenuation and of thermal conductivity. The basic physico-mechanical properties of the resultant AlN-(SiC-C) composites: hardness, thermal conductivity, attenuation of the microwave energy in the frequencies range from 9.5 to 10.8 GHz have been defined.