The Rare-Earth Hexaborides

Rare-earth hexaborides (REB6 ) are composed of rare-earth elements and octahedral 3D boron units. In Chapter 1, rare-earth elements were examined in detail; in this part, the REB6 will be explained. Hence, rare-earth hexaborides (REB6 ) consisting of rare-earth elements and octahedral bor units are a group of ceramic materials that have a simple cubic structure with Pm3m symmetry. Their low electronic work function, low electrical resistance, and thermal expansion coefficient (in some temperature ranges), as well as high hardness and stiffness, high chemical and thermal stability, and melting points, provide a wide range of industrial uses from metallurgy to electronics.