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Ammonium perchlorate and ammonium perchlorate solid propellant thermal decomposition and explosion at pressures up to 50 kilobars
The thermal decomposition of ammonium perchlorate (AP) and ammonium-perchlorate-based composite propellants is studied using the simultaneous thermogravimetric modulated beam mass spectrometry (STMBMS) technique. The main objective of the present work is to evaluate whether the STMBMS can provide new data on these materials that will have sufficient detail on the reaction mechanisms and associated reaction kinetics to permit creation of a detailed model of the thermal decomposition process. Such a model is a necessary ingredient to engineering models of ignition and slow-cookoff for these AP-based composite propellants. Results show that the decomposition of pure AP is controlled by two processes. One occurs at lower temperatures (240 to 270 C), produces mainly H2O, O2, Cl2, N2O and HCl, and is shown to occur in the solid phase within the AP particles. 200(micro) diameter AP particles undergo 25% decomposition in the solid phase, whereas 20(micro) diameter AP particles undergo only 13% decomposition. The second process is dissociative sublimation of AP to NH3 + HClO4 followed by the decomposition of, and reaction between, these two products in the gas phase. The dissociative sublimation process occurs over the entire temperature range of AP decomposition, but only becomes dominant at temperatures above those for the solid-phase decomposition. AP-based composite propellants are used extensively in both small tactical rocket motors and large strategic rocket systems.
Pure ammonium perchlorate single crystal self deflagration, determining energy transfer mechanisms from pressure effects, combustion characteristics and subsurface profile
Granular ammonium perchlorate thermal decomposition analyzed by cinemicrography, discussing sublimation role
Pure ammonium perchlorate single crystal self deflagration, determining energy transfer mechanisms from pressure effects, combustion characteristics and subsurface profile
Ammonium perchlorate propellants sterilizability, using medium resolution mass spectrometer and regression analysis of results in thermal stability studies
Deflagration of ammonium perchlorate studied using cleaved sections of large single crystals grown from water solution, discussing burning rate and combustion zone
The short term effects of ammonium perchlorate on selected organisms were studied. A long term experiment was also designed to assess the changes incurred by ammonium perchlorate on the nitrogen and chloride contents of soil within a period of 3 years. In addition, an attempt was made to produce methane gas from anaerobic fermentation of the aquatic weed, Alternanthera philoxeroides.
Ammonium perchlorate decomposition, deflagration, sublimation, crystal growth and surface properties, using scanning electron microscope
Surface temperature of deflagrating ammonium perchlorate crystals calculated from crystal phase transition thickness
Condensed phase thermal decomposition of ammonium perchlorate, studying pressure and additives effect on kinetics
Burning solid ammonium perchlorate composite propellants surface structure observation to assess heterogeneous or subsurface reactions, using scanning electron microscope
Seven formulations of ammonium perchlorate composite propellant (APCP) are developed and their properties relevant for successful additive manufacture are characterized. Extrusion in a custom-built 3D printing system and spindle viscometry are used to collect viscosity measurements of curing primary and non-curing secondary versions of the formulations. The formulations that behave similarly to a Bingham plastic, with apparent viscosities between 4 and 8 thousand Pa*s at 30 minutes post-mix, are determined to be most suitable for printing applications. Measurements of one material show a yield stress of 1 kPa. Ambient pressure burn rates of 2.0–2.9 mm/s were measured for the compositions tested. All measured burn rates were comparable to the lower end of typical burn rates for APCP. In conclusion, the results of the characterization demonstrate a propellant suitable for use in a 3D printing system.
Effect of additives on thermal decomposition of ammonium perchlorate
The transportation hazard classification of Ammonium Perchlorate is discussed. A test program was completed and data were forwarded to retain a Class 5.1 designation (oxidizer) for AP which is shipped internationally. As a follow-on to the initial team effort to conduct AP tests existing data were examined and a matrix which catalogs test parameters and findings was compiled. A collection of test protocols is developed to standardize test methods for energetic materials of all types. The actions to date are summarized; the participating organizations and their roles as presently understood; specific findings on AP (matrix); and issues, lessons learned, and potential actions of particular interest to the propulsion community which may evolve as a result of future U.N. propellant transportation classification activities.
Mass spectrometer pyrolysis of ammonium perchlorate at low pressure
The impact of the biodegradation rate of ammonium perchlorate on the environment was studied in terms of growth, metabolic rate, and total biomass of selected animal and plant species. Brief methodology and detailed results are presented.
Remotely-operated measuring apparatus for determining freezing point curves for solutions of ammonium perchlorate in hydrazine