Probing the Reaction Mechanism for Highly Reactive Nanothermite Formulations

Formulations of aluminum nano particles for energy applications have been intensely investigated over the past few decades for their attractive energy release rate. They significantly affect propellant burn rates, enhance detonation properties, and are also used in thermite formulations (“Super-Thermites”) [1]; however, the reactive properties remain poorly understood. The mechanism behind these energetic systems is currently under debate. On one hand, Al nano particles possess a protective alumina shell in their native state leading to the belief of the inter-diffusion mechanism (oxidizer and fuel through shell) during reaction [2]. On the other hand, a more violent mechanism where the particle shell disintegrates upon the melting of the aluminum core has also been proposed [3]. This study used electron microscopy to probe the underlying mechanism through a forensic analysis of the products of these reactions.