Safety and performance characteristics of thermite systems: from powders to 3D printed lattices

The reaction in thermite powders is a highly complex process. Developing a true understanding of this process involves an understanding of the various length and time scales, as well as the non-equilibrium and equilibrium processes as fuel and oxide particles react to form mixed-phase products on a rapid time scale. In this work, we present an overview of our work, which ranges from loose-powder combustion testing to 3D printed lattices of thermite. Specifically, we explored the dynamic formation of mesoparticles and the resultant multi-phase expansion of these particles as they are entrained in a gas stream. Additive manufacturing (AM) was then used to probe how the printed architecture can be used to manipulate the reactivity, by affecting the forward energy transport through design of the structure. A materials design plot (i.e., an "Ashby Diagram") was constructed to quantify the control AM offers for these materials.

This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.