Barium hexaboride is a hard material with a high
melting point
The melting point (or, rarely, liquefaction point) of a substance is the temperature at which it changes state from solid to liquid. At the melting point the solid and liquid phase exist in equilibrium. The melting point of a substance depends ...
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It can be formed by passing a barium vapour at >750 °C over boron crystals:
:
However, it can also be formed by reacting barium chloride with boron in two stages: firstly at 900 °C for 30 minutes and then at 1,500 °C for 60 minutes.
Potential applications
Barium hexaboride has been considered as a candidate for use in hot-cathode electron guns.
References
Barium compounds
Borides
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