Morphology of Aluminum Nanopowder Combustion Products in a Magnetic Field in Air

Abstract

The microstructure of aluminum nanopowder combustion crystalline products in air and the influence of a constant magnetic field (with induction of 0.3 T) on their structures have been studied. It was revealed that in the combustion products of free-poured aluminum nanopowder two-level whiskers are present. Hexagonal single crystals are formed by combustion in air in a homogeneous magnetic field, and in case of inhomogeneous magnetic field (with induction of 0.3 T) faceted elongated crystals of micron size are generated. The crystallites of such structure are formed due to the mass transfer of the combustion products in the direction of thermal flows. Ordered six-sided crystal structures are formed by overcooling the oxidation products by the action of magnetic field and by increasing the mobility of their structural units in recrystallization thermal wave. According to electron- microscope investigation the formation of the faceted crystals is possible with optimal sizes of combustion product particles.

Influence of Microwave and Electron Beam Irradiation on Composition of Aluminum Nanopowder

“…Thereby, the increase of metal Al content in aluminum nanopowders subjected to microwave radiation and electron beam is experimentally proved. This results can be applied in industrial applications [20][21][22][23][24][25][26][27].…”

Measuring the Changes in Copper Nanopowder Conductivity during Heating as a Method for Diagnosing its Thermal Stability

“…It must be noted that the applicability of this method to the diagnostics of other nanopowders (including modified ones [11][12][13][14][15][16][17]) requires additional verification. Nevertheless, if combined with such methods as differential thermal analysis, electrochemical research methods [18][19][20][21][22][23][24][25], X-ray structural analysis [26][27][28][29] and X-ray phase [30] analysis, the method suggested in the article can be used for researching the physical and chemical processes taking place in nanopowders in the course of heating and oxidation [31].…”

The Resource-Saving Technology of Aluminum Nitride Obtaining During Combustion of Aluminum Nanopowder in Air

“…The obtained powder is collected in the powder collector (7). The gas purified from the powder is fed back into the explosion chamber (9) by means of the gas circulation system (8). The volume of the explosion chamber (9) before exploitation is evacuated and then filled with the required gas.…”

“…% of aluminium nitride is stabilized in the final combustion products [7][8][9][10]. Even the first investigations of aluminum nanopowder combustion [11] showed, that the combustion of relatively small samples (less than 0.5 g) took place in a single step (600-800 °C), during which aluminum nitride did not form.…”