A “riding” combustion mode in CuO/Al reactive multilayer nano-foils

Abstract

Reactive multilayer nano-foils possess high heat release and combustion temperature, which makes them very attractive for advanced applications, such as materials joining materials, tuning ignition and actuation, energy microsources, and others. The combustion mechanism of CuO/Al foils has not been adequately described yet. In this work, we report experimental evidence of an amazing combustion mode in CuO/Al reactive multilayer nano-foils. A set of droplets of molten combustion products forms behind the reaction front and “rides” this front under the action of surface tension. When the combustion front arrives at the edge of substrate and stops, the droplets start to fly-by inertia along-track direction of the combustion propagation. Thus, the combustion front can throw hot micro-droplets toward a predetermined target to perform some specific action, e.g., distance ignition, actuating pulse, or energy transfer.