Mathematical Models of the Coating of Energetic Grains Upon Diffusion of Deterrents and Experimental Validation

The coating of energetic grains with deterrents and the determination of the coating thickness (the concentration distribution of the deterrent in the grain) are challenges which currently require lengthy trial and error procedures for correct implementation. Here series of analytical models were developed to describe the diffusion of a deterrent into grains which exhibit differing geometries. Two experimental methods involving fluorescence and thermo gravimetric analysis were also developed to facilitate the determination of the diffusion coefficient of the deterrent into the energetic grain using an inverse problem solution methodology on one hand and the validation of the mathematical models and the determined diffusion coefficients on the other. The theoretical results compared favorably with the experimental findings.