DETONATION CHARACTERISTICS OF LOW DENSITY GRANULAR MATERIALS
Annual rept., 1 Jan-31 Dec 1966
STANFORD RESEARCH INST MENLO PARK CA
Pagination or Media Count:
Consideration is given to the shock initiation and propagation of detonation in granular or heterogeneous solids. Reactions in initiating shocks were studied by measuring pressure and specific volume in the shocked state 2 to 100 kbar for the physically similar granular reactive and nonreactive aggregates ammonium perchlorate a low-power, insensitive explosive and potassium chloride an inert comparison material. Longitudinal sound velocities in compacts of the same material, over a range of bulk densities and grain sizes, were also measured. Loci of shocked states for NH4ClO4 and KCl aggregates show a dramatic qualitative difference, leading us to the conclusion that reaction occurs at the shock front. This conclusion opens the possibilities that nonreactive shocks in granular explosives and propellants do not exist, that the amount of initial reaction is related to the shock pressure, and that mechanisms of buildup to steady detonation must take into account reaction from time of shock entry. Finally, a dependence of transition behavior on grain size was demonstrated the faster transition from shock to detonation occurs for smaller grain size, i.e., larger grain surface per unit volume.
- Ammunition and Explosives
- Solid Rocket Propellants