Thermal explosion in mechanically activated low-calorific-value compositions

Abstract

The effect of preliminary mechanical activation of low-calorific-value powdered formulations in a planetary ball mill on the main parameters of the subsequent thermal explosion has been studied. It has been found that in mechanically activated compositions, the initiation temperature of thermal explosion is reduced by hundreds of degrees. The maximum decrease (1300°C) is observed for the Ti + 4 wt.% C system. Regimes of preliminary mechanical activation of reaction mixtures and the subsequent thermal explosion conditions producing Ti3Al and Ni3Al single-phase intermetallic compounds with nanometer grain size were determined. For the 3Ni + Al composition, the energy accumulated during mechanical activation was evaluated. It is shown that the initiation temperature of thermal explosion in the MA compositions studied can be used to estimate the temperature that develops in the mill drums.