EFFECT OF BETA-RADIATION EXPOSURE ON THE PARAMETERS OF ALUMINUM MICROPOWDERS ACTIVITY

Abstract

The relevance. Aluminum micropowders are the precursors in many industries, such as powder metallurgy, self-propagating high-temperature synthesis of new materials, hydrogen energy, pyrotechnics and rocket fuels. Improvement of characteristics of aluminum powders contributes to their quality. The known methods of aluminum powders activation by addition of rare-earth elements, vanadium compounds, silicon, boron and other elements into the aluminum mixtures composition lead to contamination of aluminum with impurities. β-radiation exposure of micropowders with the energy less than 8 MeV does not lead to induced radioactivity and activates aluminum micropowders at the same time. The main aim of the paper was reception and explanation of experimental results on the activity parameters of aluminum micro-powders after exposure, depending on the β-radiation dose. Objects: micron-scaled aluminium powders ASD-6, ASD-6М, ASD-8, ASD-10 obtained by aluminium fusion sputtering. Methods: differential thermal analysis, X-ray diffraction analysis, the method of aluminum micropowders exposure with β-radiation, the method of calculation of the activity parameters of aluminum powders. Results. The quantitative indicators of the ASD-6, ASD-6М, ASD-8, ASD-10 aluminum micro-powders reactivity before and after exposure in the ELU-4 accelerator by 4-MeV β-radiation (i. e. the energy is significantly lower than the threshold of photonuclear reactions) were obtained in the work. The doses of powder samples exposure were 1, 2, 4 Mrad. After β-radiation exposure the oxidation start temperature decreased maximally to 205 °C; maximum oxidation rate increased by 0,19 mg/min (106 m%); the oxidation degree of the ASD-6M micropowder increased by 18,9 %, and of the ASD-10 minimally decreased by 12,3 %; the specific thermal effect of oxidation after all doses of β-radiation increased maximally for ASD-10 by 188,6 kJ/mol. Energy storage by micropowders after β-radiation is caused by the formation of a double electric layer in aluminum particles.

Keywords

• micropowders
• aluminum
• activity parameters
• exposure
• β-radiation
• stored energy
• heat of fusion