Abstract:
This research aims to contribute to the safe methodology for additive manufacturing (AM) of
energetic materials. Coating formulation processes were investigated to find a suitable method
that may enable selective laser sintering (SLS) as the safe method for fabrication of high
explosive (HE) compositions. For safety and convenience reasons, the concept demonstration
was conducted using inert explosive simulants with properties quasi-similar to the real HE.
Coating processes for simulant RDX-based microparticles by means of PCL and 3,4,5-
trimethoxybenzaldehyde (as TNT simulant) are reported. These processes were evaluated for
uniformity of coating the HE inert simulant particles with binder materials to facilitate the SLS
as the adequate binding and fabrication method. The critical constraints being the coating
effectiveness required, spherical particle morphology, micron size range (>20 μm) and a good
powder deposition and flow, and performance under SLS to make the method applicable for
HEs.
Of the coating processes investigated, suspension system and single emulsion methods gave
required particle near spherical morphology, size and uniform coating. The suspension process
appears to be suitable for the SLS of HE mocks and potential formulation methods for active
HE composites. The density was estimated to be comparable with the current HE compositions
and plastic bonded explosives (PBXs) such as C4 and PE4, produced from traditional methods. The formulation method developed and the understanding of the science behind the processes
paves the way toward safe SLS of the active HE compositions and may open avenues for further
research and development of munitions of the future.
