Abstract
To eliminate internal defects of grains developed during melt-cast charging, the formation mechanism and the trend of crystal morphology of internal defects of 2,4,6-trinitrotoluene and 2,4-dinitroanisole-based melt-cast explosives under different process conditions were simulated. The effects of solidification treatment on melt-cast explosive molding quality were investigated by combining pressurized feeding, head insulation, and water bath cooling. The single pressurized treatment technology results showed that grains were exposed to layer-by-layer solidification from outside to inside, resulting in V-shaped shrink areas of the contract cavity in the core. The defect area was proportional to the treatment temperature. However, the combination of treatment technologies, such as head insulation and water bath cooling, promoted longitudinal gradient solidification of the explosive and controllable migration of its internal defects. Moreover, the combined treatment technologies effectively improved the heat transfer efficiency of the explosive with the help of a water bath to reduce the solidification time, thus achieving highly efficient equal-material manufacturing of microdefect or zero-defect grains.