Synthesis of Porous MoSi_2 Material Fabricated by SHS (Self-Propagating High Temperature Synthesis) Process

摘要

In this study, SHS process has been employed to fabricate porous MoSi_2 material with electric-resistive heating capability through the control of pore size. The preform for SHS reaction was consisted of molybdenum powder with different sizes and silicon powder with different contained quantity. The size of the MoSi_2 particles thus formed was determined by the generated heat of combustion, not by the size of molybdenum powder. However, the pore size of MoSi_2 composite was proportional to the particle size of molybdenum powder. That is, the coarser the molybdenum powder used, the larger the formed pore size. Based on these results, the porous MoSi_2 composite could be fabricated with a desired pore size. By orienting the porous molybdenum disilicide-based material in the form of pore size gradient, porous materials used for filters with improved dirt-holding capacity can be manufactured.