Thermal explosive synthesis of MoAlB

Abstract

The thermal explosion method was used to synthesize pure MoAlB. First of all, thermodynamic evaluation of the synthesis based on the Gibbs potentials was performed. The thermal explosion was initiated by synthesis in hydrogen atmosphere at 500–900 °C. The analysis of the synthesized materials was carried out by X-ray diffraction and electron microscopy along with local chemical analysis. As a result, a monophase MoAlB powder with the elongated plate-like crystals with a thickness of 250–500 nm and a length of 10–15 μm in an equiatomic ratio of elements with lattice parameters a = 3.2114 Å, b = 13.9736 Å, c = 3.1034 Å were synthesized. Thus, for the first time, a mechanism has been proposed for preparing the MoAlB phase by thermal explosion through the borane's decomposition, which is probably realized during the synthesis in hydrogen medium.