dc.description.abstract | PBXN-5, a HMX based explosive composition for press filling has been studied in Closed Vessel for characterisation of
burning properties. PBXN-5 has been tested as powder and in form of pressed pellets. Pellets have been pressed and
tested with four different densities from 1.59 g/cm3 to 1.826 g/cm3. The purpose with the CV-testing was to see if we
were able to observe differences in the burning properties as function of differences in density of the pellets.
Pressure-time curves of firings with pellets of different density show clearly that as the density of pellets increase the
burn time increase. For the loosely packed pellets the burning start on the surface of the pellets, but as the pressure
increase the burning also take place inside the pellets. For the pellets of highest density the burning take place only on
the surface of the pellets. For PBXN-5 similar burning rates for powder and pellets of high density is obtained.
Experimentally obtained impetuses, co-volumes and maximum pressures are in general lower then theoretically
calculated ones by use of the Cheetah code. The differences between experimental and theoretical values increase as the
pellet density increase. The explanation for this observation is that when the burn time increase, also the loss of energy
to the CV increases. | en_GB |