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Mg–air batteries have high theoretical energy density and cell voltage. Their use of environmentally friendly salt electrolyte and commercially available magnesium materials determines their acceptable technical and economic efficiency, safety, and ease of operation. However, the practical applicationsof Mg–air batteries arevery limited due to the polarization of magnesium anodes and the batteries' low Faraday efficiency. In this study, we considered the possibility of designingan Mg–air battery withincreased power by adapting engineering solutions developed for an Al–air battery with alkaline electrolytes. To increase the specific power of the battery, it was proposed that the internal resistance of the battery maybe reduced using a concentrated salt electrolyte. We investigated the discharge performance of a commercial alloy of AZ31 type in 15 wt.% NaCl electrolyte at current densities of 40–120 mA/cm2. The influence of a small addition of sulfosalicylic acid into the electrolyte on the discharge performance of the anode alloy was studied as well. The estimated values of the energy characteristics of the 0.5 kW Mg–air battery were compared with those of an Al–air battery with an alkaline electrolyte. [ABSTRACT FROM AUTHOR]

Summary: In this paper, we show how to conduct fast and complete oxidation of aluminum of any size in water without any additional chemicals and no extreme temperatures. Using a simple and easily repeatable experimental procedure, we studied the oxidation of coarse aluminum granules in distilled water at temperatures of 250°C to 400°C. We present the results of the oxidation experiments as well as structural analysis of the solid products by X‐Ray Diffraction and Scanning Electron Microscopy. For the first time, we have shown that aluminum is oxidized more effectively in gaseous steam than in liquid water (at same temperature). The rate of aluminum oxidation in steam increases with increasing temperature and steam pressure. Conversion degree of aluminum granules with the size of about 1 cm was 0.93 at 300°C after 4 hours; 0.96 and 1 at 350°C after 2 and 4 hours, respectively; 0.81 and 0.99 at 400°C after 1 and 2 hours, respectively. We showed that in liquid water, aluminum oxidation penetrates just a few microns into the aluminum and the reaction stops. Unlike liquid water, steam can easily penetrate through the porous layer of the solid oxidation product. We also discuss energy generation strategies for aluminum‐water reactor and propose principal schemes of aluminum‐fueled power plants. [ABSTRACT FROM AUTHOR]

The process of advanced aluminum-alumina powders production for selective laser melting was studied. The economically effective method of obtaining aluminum-alumina powdery composites for further selective laser melting was comprehensively studied. The aluminum powders with 10–20 wt. % alumina content were obtained by oxidation of aluminum in water. Aluminum oxidation was carried out at ≤200 °C. The oxidized powders were further dried at 120 °C and calcined at 600 °C. Four oxidation modes with different process temperatures (120–200 °C) and pressures (0.15–1.80 MPa) were investigated. Parameters of aluminum powders oxidation to obtain composites with 10.0, 14.5, 17.4, and 20.0 wt. % alumina have been determined. The alumina content, particle morphology, and particle size distribution for the obtained aluminum-alumina powdery composites were studied by XRD, SEM, laser diffraction, and volumetric methods. According to the obtained characteristics of aluminum-alumina powdery composites, they are suitable for the SLM process. [ABSTRACT FROM AUTHOR]