This paper presents the results of real-time monitoring of air combustion of aluminum nanopowder and its mixtures with aluminum micropowder and iron oxide III. An optical system with a brightness amplifier was used along with visual monitoring to characterize the reflectivity of the sample surface. The reflectivity was analyzed after registering by a photodiode the intensity of radiation reflected from the surface and then amplified by the brightness amplifier at 510.6- and 578.2-nm wavelengths. Analysis of the images obtained with a high-speed camera and the photodiode output oscillograms showed that the intensity of the brightness amplifier output corresponds to the main stages of the combustion process, including the beginning of combustion, spreading of the heat wave and rise of the second combustion wave. The proposed technique is adequate for real-time monitoring of the combustion process with temperatures of 2200 °C-2400 °C, which is accompanied by intensive lighting.

The intermediate and final combustion products of pressed aluminum nanopowder are studied. It is found that the main combustion product is aluminum nitride. In the intermediate stages of combustion,...

A new composite with a core–shell structure based on magnesium hydride and finely dispersed aluminum powder with an aluminum oxide shell was mechanically synthesized. We used magnesium chips to produce magnesium hydride and aluminum wire after exploitation to produce nano-sized aluminum powder. The beginning of the hydrogen release from the composite occurred at the temperature of 117 °C. The maximum desorption temperature from the MgH₂-EEWAl composite (10 wt.%) was 336 °C, compared to pure magnesium hydride—417 °C. The mass content of hydrogen in the composite was 5.5 wt.%. The positive effect of the aluminum powder produced by the electric explosion of wires method on reducing the activation energy of desorption was demonstrated. The composite’s desorption activation energy was found to be 109 ± 1 kJ/mol, while pure magnesium hydride had an activation energy of 161 ± 2 kJ/mol. The results obtained make it possible to expand the possibility of using magnesium and aluminum waste for hydrogen energy.

This work discusses an optical system with brightness amplification—a laser monitor, as well as the system's application for real-time imaging of the surface of metal nanopowders during high-temperature combustion. The advantage of the laser monitor is its combination of microscopic magnification, laser backlighting, and narrow-band filtering, which, together with high-speed video recording, makes it possible to visualize the nanopowder surface through the intense background lighting produced by a high-temperature burning sample. We used two laser-monitor schemes with short and long focal lengths to study the dynamics of the combustion process at different spatial resolutions. For compounds whose combustion is accompanied by intense scattering of the combustion products, we recommend using the laser monitor with increased monitoring distance via a mirror-imaging scheme. This proposed technique allows real-time monitoring of the high-temperature-combustion processes accompanied by intensive lighting and product scattering at a distance of 50 cm from the optical system. Both systems allow quantitative characterization of the combustion process by registering the average output of the brightness amplifier together with the overall brightness of glowing. The combustion of nanoAl + nanoFe and nanoAl + nanoFe + microAl powder mixtures was visualized using a laser monitor for the first time and compared with the combustion of aluminum nanopowder without additives.