Efficient Preparation and Performance Characterization of the HMX/F 2602 Microspheres by One-Step Granulation Process

A new one-step granulation process for preparing high melting explosive- (HMX-) based PBX was developed. HMX/F 2602 microspheres were successfully prepared by using HMX and F 2602 as the main explosive and binder, respectively. The particle morphology, particle size, crystal structure, thermal stability, and impact sensitivity of the as-prepared HMX/F 2602 microspheres were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), laser particle size analyzer, differential scanning calorimetry (DSC), and impact sensitivity test, respectively. The SEM analysis indicated successful coating of F 2602 on the surface of HMX, and the resulting particles are ellipsoidal or spherical with a median particle size of 940 nm; the XRD analysis did not show any change in the crystal structure after the coating and still has β -HNX crystal structure; according to the DSC analysis, HMX/F 2602 prepared by the new method has better thermal stability compared to that prepared by the water suspension process. The impact sensitivity of HMX/F 2602 prepared by this one-step granulation process decreased, and its characteristic height H 50 increased from 37.62 to 40.13 cm, thus significantly improving the safety performance. More importantly, this method does not need the freeze-drying process after recrystallization, thus increasing the efficiency by 2 to 3 times.