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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.
Z 5739 (OTTOKEMI) Zirconium boride, <10 µm, 99.9% Cas no 12045-64-6 - used in use of its relatively high conductivity, especially for a ceramic.