THE EFFECTS OF PROCESSING ON PYROTECHNIC INGREDIENTS. PART 1: COMPRESSIBILITY OF POWDERED MAGNESIUM AND SODIUM NITRATE AT CONSOLIDATION PRESSURES TO 10,000 PSI
PICATINNY ARSENAL DOVER NJ FELTMAN RESEARCH LABS
Pagination or Media Count:
Nonreproducibility of illuminance levels and burning rates has long been a problem with pyrotechnic compositions. One aspect of this problem is the effects of blending and consolidation on the shape and size of the particles. If the effects of consolidation pressure on particle size, permeability, or porosity vary excessively, such variations may cause nonreproducible end-item performance. An investigation revealed that increasing the loading pressures to 10,000 psi on 44, 124 and 347 micron NaNO3 causes regular decreases in premeability and porosity. The 44- and 124-micron fractions showed little or no particle size change with increasing consolidation pressure, while the 350- micron fraction showed a regular decrease. When 28.3- and 187-micron Mg powders were similarly consolidated and evaluated, their particle sizes remained constant while their permeability and porosity decreased with increasing loading pressure. The data revealed no erratic trends in particle size, permeability, or porosity. The values obtained showed trends consistent with the plasticity and frangibility of the ingredients. It was concluded that consolidation per se is not the cause of the nonreproducibility observed in the performance of pressed pyrotechnic end items.
- Inorganic Chemistry