Dispersion analysis of NiAl-TiC-Al2O3 composite powder ground in a high-energy attritorial mill

The NiAl-TiC-Al2O3 composite powder was prepared by self-propagating high-temperature synthesis (SHS) process using elemental powders as starting materials. As-prepared powder was ground by a high-energy attritorial mill for up to 40 h. The X-ray diffraction methods were used for the structure analysis of the as-prepared and ground samples. The Rietveld method was applied for the verification of the qualitative and quantitative phase composition of the studied material. The parameters of diffraction line profiles were determined by PROFIT Toraya procedure. The crystallite sizes and lattice distortions were analyzed by Williamson-Hall method. It was found that during high-energy milling a significant decrease of crystallite size is observed only for NiAl phase. The crystallite size of this phase diminishes to 17 nm when the milling time rises to 40 h. (c) 2005 Elsevier B.V. All rights reserved.