Alon-based materials prepared by SHS technique

The aim of the presented paper was preparation of the highly reactive in the sintering powders in the Al-O-N system by SHS method. Combustion reactions of metallic aluminium and corundum powder mixtures (from 15% Al-85% Al2O3 to 50% Al-50% Al2O3) were performed in nitrogen atmosphere. The obtained powders were ground and hot-pressed at 1750, 1850 and 1950 degrees C for 1 h under 25 MPa in nitrogen flow. In contrast to conventional methods, which require 24 h of the precursor heat treatment at 1200 degrees C our studies, showed that it is possible to prepare almost pure gamma-alon materials using SHS reaction. Sintering of the powders led to obtained dense materials composed of pure gamma-alon or gamma-alon-AIN composites. The phase composition of the sintered bodies was controlled by the chemical composition of the starting mixture and the sintering temperature. (c) 2006 Elsevier Ltd. All rights reserved.