Formation of intermetallic-ceramic composites from nanoreactants in a self-sustaining reaction regime

Processing of nanoreactant energetic system, Al-TiO2, in the thermal explosion mode of combustion synthesis was investigated. Simultaneous combustion synthesis and densification experiments were carried out in a uniaxial press to obtain homogeneous as well as functionally graded products of the above reactant system. It was demonstrated that TiAl3-Al2O3 composite product synthesized from Al-TiO2 reactant system retained its sub-microstructure despite a short term exposure to higher temperatures. Composite materials with densities of 96-98% of the theoretical densities were obtained. The effect of several key processing parameters such as initial composition of reactants and temperature-pressure conditions on morphology of combustion synthesized product, their phase composition, and residual porosity were investigated. DSC, XRD, SEM, and LIBS analyses were used to characterize both reactants and products.