Abstract
This work is aimed at producing a dense mullite/MoSi2 composite from a reactive blend of MoO3, SiO2 and Al by under load-combustion synthesis. Thermodynamic analyses proved the development of the entire combustion product in molten state with an adiabatic temperature of 2340 K. Diluting the reaction mixture with 25 vol.% of the combustion product was necessary to produce homogeneity between the obtained phases. The sample porosity was reduced to similar to 3.0 vol.% by controlling the pressing load, Al particle size and the delay time. The coefficient of thermal expansion of the obtained product was 5.96-8.93 x 10(-6) K-1. The obtained dense composite exhibited good oxidation resistance at 1300 degrees C and a low electrical resistivity (1.80 Omega center dot cm). (C) 2014 Elsevier Ltd. All rights reserved.