HIGH-PURITY SPONGY TITANIUM MATERIAL AND ITS PRODUCTION METHOD

摘要

A high-purity spongy titanium material containing less amounts of oxygen and metal elements is economically produced. The vacuum separation time t in a vacuum separation step is t = tO + 15 to + 35 hour where tO 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 m2/g. The amount of oxygen after cutting and crushing is suppressed to a low level even if the cutting and crushing are carried out in the atmosphere.