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Thermodynamic and melting experiments indicate considerable potential for the use of nonstoichiometric yttria as a crucible material for cold-wall induction melting of titanium metal. Experiments have shown that substoichiometric (reduced) Y2O3−x offers more resistance to attack by molten titanium, due to lower oxygen potential, but is subject to increased uptake of yttrium into solution. Yttria reacts with and contaminates molten titanium having greater than 100 °C superheat and where the crucible temperature is equal to or exceeds the melt temperature. The yttrium taken into solution, however, scavenges oxygen from the titanium solution and precipitates as Y2O3−x, reducing interstitials to acceptable levels. Normal cold-wail induction melting, using greater metal mass to contact area in a substoichiometric yttria crucible, should yield high quality titanium metal, comparable to some grades of present commercially pure metal. Development of the crucible material is continuing with studies of larger cold-...