| || Mechanism of Modifying Ballistic Properties of Propellant Formulations by Fast-Burning Inclusions
Author : Margolin, A.D. ;Denisyuk, A.P.;Pimenov, A. Yu;Fogelzang, A.E.
Source : Defence Science Journal ; Vol:48(4) ; 1998 ; pp 357-364
Subject : 623.4 Armaments and Ballistics;662.3 Propellants;66 Chemical Technology
Keywords : Composite propellants ;Combustion behaviour;Fast burning energetic materials
Abstract : "The combustion characteristics of binary compositions of fast-burning energetic materials (FBEM) with main composite propellant components like ammonium perchlorate (AP) and polymeric binders have been studied in a constant pressure bomb, and combustion mechanism has been proposed. Combustion behaviour of composite propellants containing granulated FBEM of different particle sizes has been investigated. FBEM additives as high as 40 per cent of fine particle size to a composite propellant have not been shown to influence markedly the burning rate, whereas incorporation of FBEM grains of 500 micrometer particle size allows not only a considerable increase in the burning rate but also modifies the burning rate-pressure dependence. A mechanism of combustion of propellant compositions containing FBEM grains has been evolved that allows criteria for FBEM performance and combustion stability. "
| || Influence of Cellulosic Binders on Sensitivity and Combustion Behaviour of B-KNO3 Ignition System
Author : Bhingarkar, Varsha ;Singh, Haridwar
Source : Defence Science Journal ; Vol:56(3) ; 2006 ; pp 345-351
Subject : 620.261 Explosives
Keywords : Ballistic properties;Cal-Val;Thermal analysis;Sensitivity;Binders;Ignition system;Solid rocket propellants;Rocket propellants;Nitrocellulose;Cellulogic binders;Combustion behaviour
Abstract : Boron-potassium nitrate (B-KNO3)-based compositions have been used as an effective igniter system for solid rocket propellants. A systematic study was undertaken to generate exhaustive data on B-KNO3 (25:65)-based ignition systems with cellulosic binders, viz., nitrocellulose, ethyl cellulose and plasticised ethyl cellulose. In addition, detailed investigations were carried out with PEC as binder by varying its concentration from 2-10 per cent in the same system. The experimental compositions (B-KNO3: binder) were evaluated by closed-vessel firing, thermal analysis, sensitivity, mechanical properties and cal-val determination. The binders significantly influenced the sensitivity and combustion behaviour of B-KNO3 compositions. The composition with nitrocellulose as binder produced high flame temperature and cal-val as compared to ethyl cellulose and plasticised ethyl cellulose-based compositions. The data indicated that the calculated flame temperature for all compositions was in the range 2716 K to 2957 K. As the plasticised ethyl cellulose content increased from 2 per cent to 10 per cent, the maximum pressure increased with decrease in heat of combustion.