Beta-tungsten

As mentioned above in the intermetallic Section, beta-tungsten, which is chemically WsO, is the prototype of the A-15 structure. The interest in WsO, or Ws01 x, is not only structural but is also based on the fact that this material is superconducting Further surprising is that, for the first time, this oxide superconductor has a higher transition temperature than that of the metal itself. Pure tungsten metal has a Tc of 15.4 mK, whereas the oxide WsO has a reported Tc of 3.35 K. Other oxide compounds such as CrsO and "MosO", which are isostructural with WsO, do not superconduct above 1.02 K. 

There are three individual phases which make up cemented carbide. In metallurgical terms, the tungsten carbide phase (WC) is referred to as the oc-phase (alpha), the binder phase (i.e., Co, Ni) as the p-phase (beta), and any other single or combination of carbide phases (TiC, Ta/NbC, etc.) as the y-phase (gamma). Other than for metal cutting applications, there is no... 

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