The use of intermetallic AlxMgy powder to obtain AlMgB14-based materials

[Display omitted] •An intermetallic Al12Mg17 compound was prepared.•AlMgB14-based materials were obtained from Al12Mg17 powder and boron powder.•The XRD results of the obtained AlMgB14-based materials was obtained.•The friction coefficient curves of the AlMgB14-based materials were discussed.•The AlMgB14 formation mechanism was discussed. In this work, AlMgB14-based materials were obtained from powders of the intermetallic compound Al12Mg17 and boron using hot pressing method and mechanical treatment with a planetary mill. The method for producing intermetallic Al12Mg17 powder is presented. The effect of the mechanical treatment on the dispersion of the Al12Mg17 powder was investigated. The phase composition, microstructure, and properties (density, hardness and coefficient of friction) of the AlMgB14-based materials were investigated. The hardness of the obtained sample is 31.9 GPa, and the density is 2.35 g/cm3 (90% of theoretical density). The friction coefficient under dry conditions is 0.38. The friction coefficient under lubricated conditions (LITOL-24 lubricant) is 0.18. The mechanism of AlMgB14 formation was investigated. When using the intermetallic Al12Mg17 powder as a raw precursor of the Al-Mg-B powder mixture, the AlMgB14 phase is formed by direct boration of AlxMg1-xB2 diboride, while the formation of spinel MgAl2O4 phase is due to contamination of the raw boron powder.