Ignition of High Energy Material Containing Ultradispersed Al/B Powder

This paper presents the characteristics of the oxidation of ultrafine aluminum powders of the Alex grade and a mechanical mixture containing Alex/B boron powder. The features of the ignition of high-energy materials containing ammonium perchlorate, butadiene rubber, and ultrafine metal powders, when heated by a radiant heat flux, are studied. It is established by thermal analysis that the rate of change in the mass of the sample and the total specific heat release during the oxidation of powdered aluminum diboride (Alex/B) in air significantly exceed the values of aluminum powder (Alex). Measurements on an experimental setup based on continuous CO2-laser and high-speed visualization of the stages of the response and development of flame processes show that the use of Alex/B in the composition of a high-energy material does not lead to a significant change in the time characteristics of ignition under the same heating conditions. At the same time, the intensity of the outflow of gaseous decomposition products with metal particles from the combustion surface of the fuel composition increases due to an increase in the heat flux in the zone of the gas-phase reactions and on the surface of the reactive fuel layer during the oxidation of aluminum and boron particles.

Automated summary

This paper investigates the ignition characteristics of high-energy materials under radiant heat flux, as well as the oxidation characteristics of ultrafine aluminum powders of the Alex grade and a mechanical mixture containing Alex/B boron powder. The results show that the use of Alex/B does not significantly change the ignition time characteristics under the same heating conditions, but increases the outflow intensity of gaseous decomposition products from the combustion surface.