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Zirconium diboride (ZrB2) is a highly covalent refractory ceramic material with a hexagonal crystal structure. ZrB2 is an ultra high temperature ceramic (UHTC) with a melting point of 3246 °C.
NZ 108 (OTTO) Zirconium diboride, APS 100-200 nm, 99.5% Cas 12045-64-6 - used as an aerospace refractory, in cutting tools, and to protect thermocouple tubes.