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Zirconium boride, also known as zirconium diboride, a gray metallic crystals or powders. Mohs hardness 8, electrical resistivity 9.2 micro-ohm-cm (20°C), excellent thermal shock resistance, poor oxidation resistance above 1100°C. It was attacked very little by cold HCl, more rapidly by HNO3, and is dissolved by aqua regia. It reacts with H2SO4 and is readily attacked by fused alkali hydroxides, carbonates, and disulfides.Zirconium diboride (ZrB2) is a transition metal boride with a hexagonal crystal structure and P6/mmm symmetry. ZrB2 has a combination of metallic, ionic, and covalent bonds. Due to its strong covalent bonds, ZrB2 has a high melting temperature of 3250°C. This melting temperature classifies ZrB2 as an ultra-high temperature ceramic (UHTC). UHTCs have been proposed for use in many different applications due to their high melting temperatures (>3000°C), as well as their high strength and chemical inertness.

개요Zirconium diboride (ZrB2) is a highly covalent refractory ceramic material with a hexagonal crystal structure. ZrB2 is known as a UHTC with a melting point of 3246
C. This together with its relatively low density of B6.09 g/cm3 (measured density may be higher due to hafnium impurities) and good high-temperature strength makes it a contender for high-temperature aerospace applications, for example, hypersonic flight or rocket propulsion systems. It is an unusual ceramic with relatively high thermal and electrical conductivities.

용도Zirconium boride is use to improve resistance in zirconia-based, carbon-bonded refractories in contact with ferrous melts. Used in nuclear applications, aerospace refractory, in cutting tools and to protect thermocouple tubes. It also used in use of its relatively high conductivity, especially for a ceramic.