ELECTROCHEMICAL BURN RATE ACCELERATION

Abstract

An electrochemical mechanism of accelerating the burn rate of pyrotechnic compositions and composite propellants is presented. Magnesium-Teflon-graphite fluoride-graphite (MTGFG) compositions were used as the model system to demonstrate the effect. Electric currents are generated in situ by electrochemical cell reactions in the composition itself by introducing materials with differing electrochemical potentials and an electrolyte into the composition. Electric currents flow through the combusting surface, where materials melt and allow ion transport. The electrochemical cell is shorted at the burning surface providing more heat feedback than the back radiation from the flame alone accelerating the combustion considerably. No external power source nor auxiliary electrodes are required to increase the burn rate by electric currents like with methods hitherto known. Up to a 2.5-fold increase in the burn rate of baseline composition was achieved by using graphite as the cathode material, the magnesium powder in the composition as anode, and graphite fluoride (GF) as depolarizer and oxidizer in the cell reactions. Various electrolytes were investigated keeping the base composition otherwise unchanged.