СИНТЕЗ ВЫСОКОТЕМПЕРАТУРНОЙ КЕРАМИКИ НА ОСНОВЕ Mo5SiB2 В РЕЖИМЕ ГОРЕНИЯ

The work is devoted to the synthesis and investigation of ceramic material on the basis of Mo 5 SiB 2 chemical compound ( T 2 -phase). The effect of initial temperature on key parameters of combustion process is shown. It is found that reaction mixture preheating allows initiating combustion in the self-oscillatory mode, thus initial temperature dependences of combustion temperature and rate have linear character. The effective SHS- process activation energy value is calculated. Some variants of chemical reactions between Mo, Si and B are proposed for explanation of the com- bustion mechanism in the examined ternary system. Compact samples are obtained using the power SHS-compaction. The phase composition, structure, and properties of synthesized ceramic materials, in which Mo 5 SiB 2 grains are the basic component with average size of 10–20 μm, have been studied. The lines of Mo 3 Si and Mo intermediate phases, which total fraction does not exceed 4 %, are identified as well. The produced T 2 - phase based material possesses high specific density and hardness.