Characteristics of Solid Propellants

E. W. Price, Review of the Combustion Instability Characteristics of Solid Propellants, in Advances in Tactical Rocket Propulsion, S. S. Penner, ed., AGARD Conference Proceedings no. 1, Maidenhead, England Technivision Services, 1968, 139-194. 

N. Kubota, "Survey of Rocket PropeUants and Their Combustion Characteristics," in K. K. Kuo and M. Summerfield, eds.. Fundamentals of Solid Propellant Combustion, Vol. 90, Progress in Astronautics and Aeronautics, AJAA, 1984. 

Scanning Electron Microscopy in the Study of Solid Propellant Combustion. Part 111. The Surface Structure and Profile Characteristics of Burning Composite Solid Propellants , NavWeps-Cent r TP 5142-Part 3 (1971) 48) B.T. 

Many of the tests described earlier have been applied in surveillance studies of solid propellants. Both response and failure characteristics may be followed as a function of time during storage at various conditions. Physicochemical analysis of specimens before and after exposure to... 

Gun propellants are manufactured by three different methods (i) solvent method (ii) semi-solvent method and (iii) solventless method. The solvent method is that most commonly used for the manufacture of gun propellants. Selection of the method for manufacture basically depends on the properties of the raw materials and the propellant formulation. While there are limitations for the manufacture of gun propellants by solventless and semi-solvent methods, the solvent method may be applied for almost every gun propellant formulation. The solid-liquid ratio of the ingredients and the type of nitrocellulose used usually decide the feasibility of manufacture by the solventless method. Some characteristics of solid gun propellants are given in Table 4.1. 

Decomposition of Irradiated a-Lead Azide , BNL-6632, Brookhaven Natl Lab, Upton (1963) 112) J.G. Horton, Exploration of Solid Propellant Characteristics under Simulated Space Conditions , Proc 1963 Mtg Inst of Environmental Sciences (1963), 177—84 113) G. 

Early in the development of solid propellant, the asphalt composites were found to have poor physical properties, such as cracking under normal temperature cycling, poor tensile characteristics, etc. They were replaced with the elastomeric polymers which have become the present-day binders. The first of these was Thiokol rubber, a polysulfide rubber, whichgives the propellant with good physical properties. The presence of the sulfur atom in the Thiokol rubber decreases the performance compared to a CHO polymer thus the most frequently used binders are polyurethane, polybutadiene acrylic acid (PBAA), epoxy resin, etc. The choice of the latter binders is made with regard to physical properties rather than performance. 

The procedures used for estimating the service life of solid rocket and gun propulsion systems include physical and chemical tests after storage at elevated temperatures under simulated field conditions, modeling and simulation of propellant strains and bond tine characteristics, measurements of stabilizer content, periodic surveillance tests of systems received after storage in the field, and extrapolation of the service life from the detailed data obtained (21—33). 

For the region near the attachment point, Mullis found a strong effect of axial position on flux, but no satisfactory general correlation for this effect. In addition, he found no quantitative relation for the heat-transfer characteristics of jets directed toward the propellant surface. Under most conditions studied by Mullis, the radiation contribution is approximately 10% of the convective flux. The effects of solid-particle impingement were not investigated. 

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