Chemical heat sources

Work was undertaken to identify chemical heat sources which can being a metal such as aluminum contained in a tantalum vessel from ambient to 1500C. Five different fuels and twelve different oxidizers were identified as potential components in a mixture possessed of the desired characteristics: large amount of heat available at 2000K, good good heat transfer characteristics, insensitivity, long term stability, and no reaction products boiling below 1800K. Six mixtures were selected for additional tests on the basis of: (1) usefulness in the device, itself and (2) usefulness in characterizing other mixtures in the same class. The results are: All mixtures are dry, non-hygroscopic, non-pyrophoric powders which are stable, non-corrosive, and insensitive (ignition temperatures above 380C) yet they are ignited easily and reliably by standard means. All mixtures may be pressed in place, without binders, to form relatively tough solids. The information now available is sufficient to begin development of one or more prototype devices.