Anomalous combustion effects during mechanical alloying

Abstract

Combustion in solid-state displacement reactions during mechanical alloying has been investigated. It was found that mechanical alloying decreases the critical reaction temperature at which unstable combustion reactions propagate. Some reactions exhibited an unusual "interrupted combustion" effect, whereby reactant powders which had been milled for subcombustion times and left to age at room temperature combusted on the immediate resumption of milling. For one reaction, the reduction of ZnO by Ti, combustion was only observed in aged powders. Interrupted combustion is associated with the diffusion of reactant species during aging and with a decrease in the temperature required for combustion..