Heating of Particles with an Aluminum Core and a Hydroxide Shell

Particles with an aluminum core and a hydroxide shell obtained by low-temperature (up to 100°C) oxidation of spherical aluminum micron particles with water are studied. Processes occurring upon heating these particles up to 750°C in a controlled gaseous atmosphere are analyzed. The composition and amount of released gas-phase products are studied, and their nature is determined. The transformation of the shell as a result of the phase transition of aluminum hydroxide to oxide is considered. The mechanism of formation of cracks as a result of thermal expansion of the core and shell during the heating of the particle is considered. Outcrops of aluminum onto the surface of the oxide shell after reaching the melting point of aluminum are noted. It is proposed to use aluminum extruded onto the surface for the formation of bonds between the particles upon executing 3D printing.