Self-Propagating High-Temperature Synthesis of Porous Molybdenum Disilicide Composites

Microwave processing combined with combustion synthesis was used to fabricate intermetallic composite foam. Internal microwave heating initiated ignition at center of the sample and combustion wave front propagated radially outwards. Open-cell porous MoSi2 intermetallics with adjustable pore characteristics were successfully produced from MoO3, SiO2, Mg and C raw materials. Manipulating volume fraction and particle size of the utilized carbon, porosity and pore size of MoSi2 intermetallics were easily controlled. Their values were in the ranges of 18-56% and 0.4-2.0 mm, respectively. From thermodynamic analyses of MoO3–xMg–yC system, optimal ranges of x and y coefficients were so found to ensure complete reduction of MoO3 to metallic molybdenum. The influence of x and y values on the process parameters like temperature, front propagation velocity, phase composition and the structure of products were experimentally investigated

Keywords:

Metal Foam , Composite materials , SHS process , Molybdenum Disilicide