Yttrium hexaborate
English name: Yttrium hexaborate
Chemical formula: YB6
Molecular weight: 237.9
Melting point: 2345 ℃
Density: 2.23g/cm3

Application: Yttrium boride has the characteristics of high hardness, high elastic modulus, high melting point and excellent thermal stability, among which the most common forms are Yttrium tetraboride (yb4) and Yttrium hexaboride (yb6). yb4 and yb6 have tetragonal crystal structure and cubic crystal structure respectively, and both have low brittleness and good mechanical failure tolerance, which is expected to be applied in the field of ultra-high temperature ceramics to improve the toughness and ductility of ceramic materials. Compared with yb4, yb6 ceramics are more likely to form dislocations during deformation, and the ductility of the material is better. At the same time, rare earth hexaboride also has the characteristics of low work function, high conductivity, high emission current density and strong thermal radiation resistance, and is a potential candidate material in the field of electron emission materials, thermoelectric materials and superconducting materials. Therefore, the application prospect of rare earth hexaborides such as yb6 is very broad. However, the structure of yb6 with a small cation radius is unstable at high temperatures and will decompose into yb4 above 1700℃. Because of its high melting point, high hardness and strength, low density, oxidation resistance, excellent chemical stability, good electrical and magnetic properties and other excellent physicochemical and electrical properties, Yttrium boride (YB6/YB4) is a kind of high temperature thermoelectric material suitable for ultra-high temperature environment and nuclear environment and other extreme environment applications. Yttrium boride (YB6/YB4) is used in various fields requiring high-temperature thermoelectric component materials such as hypersonic vehicle leading edge thermal protection systems and rocket propulsion components.