Thermal Explosion in a Powder Mixture of Aluminum with Nickel Preactivated in a Low-Energy Laboratory Mill

This paper describes the effect of preliminary low-energy mechanical activation of nickel powder on the thermal explosion of a Ni3Al intermetallic compound. Two synthesis methods are considered. The first method requires that a mixture is continuously heated by an external energy source. The second method requires that an external source is turned off upon reaching a certain temperature. It is revealed that low-energy mechanical activation of nickel intensifies the Ni3Al synthesis. With continuous heating, the ignition temperature does not depend on activation time and is equal to the melting point of aluminum. In the case of heating with an external source turned off, preliminary activation of nickel reduces the solid-phase ignition temperature. It is established that nickel activation in a laboratory mill allows one to eliminate its passivation factors.