MoAlB fine powders were prepared in molten NaCl from Al, B and Mo powders. The effects of key parameters affecting the synthesis process and phase morphology were examined and the underpinning mechanisms proposed. MoAlB product particles exhibited different shapes/sizes, as follows: spherical grains (1~3 μm), plate-like particles (<5 μm in diameter) and columnar crystals with lengths up to 20 μm and diameters up to 5 μm, resultant from different reaction processes. Phase pure MoAlB was synthesised under the following optimal conditions: use of 140% excess Al and 6 h of firing at 1000 °C. This temperature was at least 100 °C lower than required by other methods/techniques previously reported. At the synthesis condition, Mo first reacted with Al and B, forming Al₈Mo₃ and MoB, respectively, which further reacted with excess Al to form Al-rich Al–Mo phases and MoAlB. The Al-rich Al–Mo phases further reacted with the residual B, forming additional MoAlB. The molten NaCl played an important role in accelerating the overall synthesis process.

Submicron-sized (~200 nm) aluminium boron carbide (Al₈B₄C₇) particles were synthesised from Al, B₄C and carbon black raw materials in a molten NaCl-based salt at a relatively low temperature. The effects of the salt type/assembly and the firing temperature on the synthesis process were examined, and the relevant reaction mechanisms discussed. The molten salt played an important role in the Al₈B₄C₇ formation process. By using a combined salt of 95%NaCl + 5%NaF, an effective liquid reaction medium was formed, greatly facilitating the Al₈B₄C₇ formation. As a result, essentially phase-pure Al₈B₄C₇ was obtained after 6 h of firing at 1250 °C. This temperature was 350–550 °C lower than that required by the conventional direct reaction and thermal reduction methods.

Alumina-titanium diboride (Al₂O₃-TiB₂) composite powders were synthesised via aluminothermic reduction of TiO₂ and B₂O₃, mediated by a molten chloride salt (NaCl, KCl, or MgCl₂). The effects of salt type, initial batch composition, and firing temperature/time on the phase formation and overall reaction extent were examined. Based on the results and equilibrium thermodynamic calculations, the mechanisms underpinning the reaction/synthesis processes were clarified. Given their evaporation losses at test temperatures, appropriately excessive amounts of Al and B₂O₃ are needed to complete the synthesis reaction. Following this, phase-pure Al₂O₃-TiB₂ composite powders composed of 0.3–0.6 μm Al₂O₃ and 30–60 nm TiB₂ particles were successfully fabricated in NaCl after 5 h at 1050 °C. By increasing the firing temperature to 1150 °C, the time required to complete the synthesis reaction could be reduced to 4 h, although the sizes of Al₂O₃ and TiB₂ particles in the resultant phase pure composite powder increased slightly to 1–2 μm and 100–200 nm, respectively.