Low temperature atmospheric synthesis of WAlB and Mn2AlB2 MAB phases by modified molten salt shielded synthesis method

Abstract

Nowadays, transition metal-based boride-like layered MAB phases are getting more attention due to their excellent combination of metal-ceramic properties, like good thermal and electrical conductivity, oxidation and thermal shock resistance, excellent wear resistance etc. So far, WAlB was synthesized at high temperature (1550 °C) with 24 hr soaking time by aluminium flux technique with nominal single-phase purity, which requires huge investment and production costs. However, Mn2AlB2 was recently synthesized using KBr salt via molten salt shielded synthesis (MS3) at a relatively low temperature 1000 °C for a longer soaking time (12 hr) which may enhance the chances of oxidation. Therefore, the motivation of this work is to synthesize WAlB and Mn2AlB2 MAB phase at lower temperatures with high purity via a newly developed simple, cost-effective, environmental-friendly method named modified molten salt shielded synthesis method. This paper synthesized both these phases with high yield at lower temperatures and much shorter soaking time than earlier reported literature.