Fabrication, structure, and properties of TiB2-AlN ceramics

Conductive TiB2–AlN ceramics were prepared by self-propagating high-temperature synthesis in a filtration combustion regime at high nitrogen pressures. The effect of nitrogen pressure on the combustion rate and the Al metal content of the reaction product was studied. The combustion rate was also shown to depend on the composition of the starting mixture. The phase composition of the ceramics was determined by x-ray diffraction, chemical analysis, and microstructural examination. The porosity, electrical resistivity, and bending strength of the ceramics were measured. The resistivity of the materials was found to change sharply at a TiB2 content of 19 vol %. This effect was interpreted as due to the formation of a fractal structure.