Beryllium oxide (BeO) is a white crystalline oxide. It is obtained from beryllium or beryllium compounds by ignition in the air. The sintered beryllium oxide (beryllia), which is very stable, has ceramic characteristics. It is similar to aluminium oxide (Al2O3), is highly fire resistant (melting point: 2570°C), and has polymorphism. Beryllium oxide was previously called glucina.
Beryllium oxide formed at high temperatures (>800°C) is inert but may be easily dissolved in hot aqueous ammonium bifluoride (NH4HF2) or a hot solution of concentrated sulfuric acid (H2SO4) and ammonium sulfate ((NH4)2SO4).>
Beryllium oxide is used in many high-performance semiconductor parts for applications such as radio equipment because it has good thermal conductivity while also being a good electrical insulator. It is also used as a structural ceramic for high-performance vacuum tubes, magnetrons, and gas lasers.
