Water Bath Separation and Morphology Characterization of HMX Particles in DNP/HMX Melt-Cast Explosives

Solid particle dissolution and recrystallization during the solidification and cooling process of meltcast explosives can alter particle crystal morphology and generate potentially hazardous hotspots, leading to significant safety and quality concerns. Traditional hot-stage microcopy (HSM) can investigate the effect of particle dissolution and recrystallization on particle morphology. However, this method only observes the particle’s two-dimensional surface morphology and the resultant micrograph appears blurred due to the fact the observed particle is not separated from the matrix explosive and the resolution of the microscope is low. To address these limitations, a simple and efficient method, called water bath separation (WBS) method, was developed to extract tetramethylene-tetranitramine (HMX) particles from 3,4-dinitropyrazole (DNP) matrix. The effectiveness of the WBS method for DNP/HMX melt-cast explosives was validated experimentally using scanning electron microscopy (SEM).