Qualitatively and quantitatively predicting the front velocity in binary reactive systems

Abstract

Reactive multilayer systems, due to their fast and highly localized heat release, are widely applied in various technologies. To tailor their properties to specific applications, there is still a lot of ongoing research on the engineering and prediction of their reaction properties. In this work, the focus is going beyond multilayers to binary Al/Ni reactive systems. Based on molecular dynamics (MD) simulations, two crucial geometrical parameters that have the biggest influence on the front velocity are identified. The fraction of interfaces and the fraction of premixed interalayers at the Al–Ni interfaces allow for a qualitative comparison of various binary reactive systems. Beyond that, based on the two parameters, a simple analytical model to predict the front velocity, which is also compatible with existing models for multilayers, is developed. It is shown to be suitable to describe both results from MD simulations and experimental results. Furthermore, it is used to predict the front velocities of Ni nanoparticles in an Al matrix as well as interpenetrating Al–Ni networks.