HIGH-PURITY SPONGY TITANIUM MATERIAL AND ITS PRODUCTION METHOD

摘要

The present invention relates to an economical method of producing a high-purity spongy titanium material containing less amounts of oxygen and metal elements. Using Croll's method for production of a high-purity spongy titanium material the vacuum separation time t in a vacuum separation step is t = t0 + (15 ( 35) hour where t0 is the time from the start of the vacuum separation till the time when the temperature of the central part of the material in a reaction vessel reaches to a stable temperature. At and near the central part of the material where the amounts of metal elements are a little, the specific area measured by the BET method is below 0.05 m<2>/g.