Method for purifying titanium material

Abstract

A method for refining a titanium material, in which oxygen contained in a titanium material made of a pure titanium, a titanium alloy or an intermetallic compound containing titanium as one of main components is removed, the method includes: a first melting step of melting the titanium material under a noble gas atmosphere containing 5 to 70 vol % of hydrogen, thereby introducing hydrogen into a melt of the titanium material; and a second melting step of melting the titanium material into which hydrogen has been introduced in the first melting step under a noble gas atmosphere, thereby removing oxygen contained in the titanium material from the melt of the titanium material together with the hydrogen. Each of the first melting step and the second melting step is carried out at least once.

1 . A method for refining a titanium material, in which oxygen contained in a titanium material made of a pure titanium, a titanium alloy or an intermetallic compound containing titanium as one of main components is removed, the method comprising:
 a first melting step of melting the titanium material under a noble gas atmosphere containing 5 to 70 vol % of hydrogen, thereby introducing hydrogen into a melt of the titanium material; and   a second melting step of melting the titanium material into which hydrogen has been introduced in the first melting step under a noble gas atmosphere, thereby removing oxygen contained in the titanium material from the melt of the titanium material together with the hydrogen,   wherein each of the first melting step and the second melting step is carried out at least once.   
     
     
         2 . The method for refining a titanium material according to  claim 1 , further comprising a heat treatment step of retaining the titanium material for 15 minutes or more under the condition of a degree of vacuum of 1×10 −2  to 1×10 −4  Pa and a retention temperature of 600 to 1,200° C. after termination of the second melting step, thereby removing hydrogen from the titanium material.