The results of dynamic mass spectrometric studies of the composition of the
gas-phase products formed in a wave of solid-phase burning spreading throu
gh Mo + B, Nb + B, and Ta + C SHS systems show that concentrations of boron
and carbon oxides and suboxides vary periodically with frequencies corresp
onding to pulsations of burning waves in these systems known from previous
investigations. A kinetic structure of the combustion wave is analyzed to d
emonstrate that self-sustaining oscillations attributed previously to therm
al instability can be interpreted within a kinetic model of a multistage pr
ocess involving gas-phase transport of reagents.