Mechanical properties of high density MgAl2O4/TiC/W composite prepared via self-propagating synthesis with direct consolidation technique

Abstract

MgAl2O4-TiC/W composite has been successfully insitu synthesized in a high dense form using combustion synthesis under-load technology. The process was applied to a blend of titanium dioxide, carbon magnesium oxide, aluminum metal and tungsten carbide powders. The different parameters affecting the synthesis of the target composite were investigated. This included the effect of aluminium particle size (37, 18.2, 5.6 μm), carbon stoichiometry (0.7–0.9), WC wt% (10–30 wt%). The obtained results showed that, 18.2 μm Al, 0.8 carbon stoichiometry and 234 MPa load were necessary to obtain high dense composite 2.4 vol% porosity and hardness of 1535 HV with homogeneous microstructure. Addition of 20 wt% WC highly improved the microstructure and the sample hardness was increased to 1754 HV with a sample porosity of ∼3.0 vol%. Thermodynamic study of the different reactions involved in the combustion process was also conducted.