| || Size and Shape of Ammonium Perchlorate and their Influence on Properties of Composite Propellant
Author : Jain, Sunil ;Mehilal;Nandagopal, S. ;Singh, P.P. ;Radhakrishnan, K.K. ;Bhattacharya, B.
Source : Defence Science Journal ; Vol:59(3) ; 2009 ; pp 294-299
Subject : 54 Chemistry;620.261 Explosives;662.3 Propellants
Keywords : Ammonium perchlorate;Average particle size;Particle shape;Composite propellant;Shape factor
Abstract : Most of the composite propellant compositions contain solid loading up to 86 per cent. The main solid ingredients of composite propellant are ammonium perchlorate (AP) and aluminium powder. Therefore, it is a must to characterise these to improve processibility and quality of composite propellant. Effect of particle size on propellants slurry viscosity and ballistic parameters are well documented, however, the effect of oxidizer particle shape is not reported. In the present study, different methods for size and shape characterization are discussed and effect of size and shape of AP on composite propellant properties are studied. The data indicate that as size of AP decreases, propellant slurry viscosity increases and burn rate increases. The particles having higher shape factor provides less endof mix (EOM) viscosity of propellant slurry and burn rate. Further, effect of size of ground AP on shape is also investigated. From the data thus obtained, it is inferred that as size of ground AP decreases, shape factor decreases, and particles become more irregular in shape.