The high pressure crystal growth of sodium beta-alumina

The authors have made use of a recently developed crystal growth method called edge-defined, film-fed growth (EFG), which enables a variety of crystals to be grown having any constant cross-sectional shape. To counter the problem of sodium vaporization, a high pressure (300 psi), inert gas, EFG crystal growth chamber has been constructed, and to contain the reactive melt, both the crucible and the crystal-shaping dies were fabricated from iridium