Combustion synthesis of Ti3Si1-xAlxC2 solid solutions from TiC-, SiC-, and Al4C3-containing powder compacts

Preparation of the Ti(3)Si(1-x)AlxC(2) solid solution with x = 0.2-0.8 was investigated by self-propagating high-temperature synthesis (SHS) using TiC-, SiC-, and Al4C3-containing powder compacts. Due to the variation of reaction exothermicity with sample stoichiometry, the combustion temperature and reaction front velocity decreased with increasing Al content of Ti3Si1-xAlxC2 for the TiC- and Al4C3-added samples, but increased for the samples with SiC. In contrast to the formation of Ti-3(Si, Al)C-2 as the dominant phase for the TiC- and SiC-added samples, TiC was identified as the major constituent in the final products of samples adopting Al4C3. In addition, the evolution of Ti-3(Si, Al)C-2 was improved by increasing the Al content of the TiC-and SiC-added powder compacts, but deteriorated considerably upon the increase of Al4C3 in the Al4C3-containing sample. (C) 2011 Elsevier B. V. All rights reserved.