Abstract:Full conversion AlN ceramics with approximately 80% relative density were fabricated by self-propagating high-temperature synthesis(SHS) of Al particles in high pressure nitrogen. The effects of initial factors such as the content of diluent, nitrogen pressure and the porosity of compacts on the conversion and relative density of products were discussed in detail. Full conversion and relative density of AlN ceramics were synthesized by addition of appropriate diluents. At the lower level of the diluent in the sample, nitrogen gas is difficult to infiltrate due to aggregation of molten Al, Al cannot completely converse into AlN.As the content of the diluents is up to 60%, self-propagating high-temperature synthesis reaction cannot be self-sustained.With increasing of the pressure of nitrogen, the conversion of product increases and the relative density of the ceramics is improved. The low or high relative density of the sample is not benefit to improve the relative density of the ceramics.

Key words: AlN ceramics; self-propagating high-temperature synthesis; densification