Fabrication of AlMgB ₁₄ nanoparticles by high energy ball milling of bulk compound prepared by spark plasma sintering

Aluminum Magnesium Boride (BAM), an intermetallic compound, exhibits exceptional hardness, a low coefficient of friction, low density, high electrical conductivity, and outstanding thermoelectric properties. These characteristics make it a promising candidate for applications in semiconductors, as a reinforcing agent in metal and ceramic matrix composites, and as a wear-resistant coating across a wide range of temperatures. In this work, BAM nanoparticles were prepared by high-energy ball milling of constituent as a solid-state route. BAM was synthesized by spark plasma sintering of Al 12 Mg 17 intermetallic and B powders. The powders with a stoichiometric ratio were mechanically milled and sintered by SPS (40 MPa/ 1400 °C/ 5 min). It was found that the use of Al 12 Mg 17 intermetallic compound as a precursor (in comparison to the use of elemental Al and Mg) gives a high efficiency (≈92%) to synthesize BAM material with a hardness (27.98 ± 0.9 GPa) and density (2.68 ± 0.002 g/cm 3 ) close to the theoretical values. Finally, the BAM nanoparticles (the mean diameter of 32.4 nm) were successfully obtained by mechanical milling of the bulk sample, for the first time.