Safety assessment studies of a damaged high-energy solid propellant

Abstract

This article presents a study of the effects of damage on the thermal decomposition, combustion and deflagration-to-detonation transition (DDT) of the NEPE (Nitrate Ester Plasticized Polyether) propellant in order to assess its safety. The study includes: (1) to induce damage into the propellants by means of a large-scale drop-weight apparatus; (2) to observe microstructural variations of the propellant with a scanning electron microscope (SEM); (3) to investigate thermal decomposition tests; (4) to carry out closed-bomb tests and (5) to perform DDT tests. The NEPE propellant is found to be a viscoelastic material. The matrices of damaged samples are severely degraded, but the particles are not. The results of the thermal decomposition tests, closed-bomb tests and DDT tests show that the microstructural damage in the propellant has some marked effects on its thermal decomposition rate, bum rate and transition rate from deflagration to detonation. It is shown that the impact damage strongly influences on safety properties of the NEPE propellant.