Alpha + beta or beta TITANIUM ALLOY AND METHOD FOR PRODUCTION THEREOF

Abstract

A titanium alloy containing copper, which cannot be realized by a conventional method, is provided, having a composition in which copper is contained in titanium with no segregation, and having improved strength and hardness. In addition a method is also provided, in which the titanium alloy is produced at lower cost than in a conventional method. The α+β or β titanium alloy contains copper at 1 to 10 mass %, has a crystal phase of β and α phase or of β phase, is formed of crystal particles not more than 100 μm, and has a copper concentration per an arbitrary specified 1 mm 3 portion of the crystal phase at within ±40% compared to another arbitrary specified portion. The α+β or β titanium alloy is produced by mixing 1 to 10 mass % of copper powder and the remainder of titanium alloy powder and then pressing and forming while being heated. The method for production of the α+β or β titanium alloy has a step of mixing 1 to 10 mass % of copper powder and the remainder of titanium alloy powder and a step of pressing and forming the mixture while being heated.

1 . (Amended) An α+β or β titanium alloy comprising:
 copper contained in a range of 1 to 10 mass % as a result of adding the copper powder, and 
 at least aluminum and vanadium, 
 wherein the alloy crystal phase is β or α and β phase, 
 the size of a crystal phase consisting particles not greater than 100 μm, and 
 the copper concentration per 1 mm 3  of an arbitrary specified portion in the crystal phase is within ±40% compared to another arbitrary specified portion. 
 
     
     
         2 . The α+β or β type titanium alloy according to  claim 1 , wherein the titanium alloy is obtained by mixing copper powder and titanium alloy powder and then pressing and forming the mixed powder while being heated. 
     
     
         3 . The α+β or β type titanium alloy according to  claim 2 , wherein the titanium alloy powder is produced from raw titanium alloy, and the titanium alloy contains at least one selected from molybdenum, iron, chromium, and tin. 
     
     
         4 . A method for production of α+β or β titanium alloy containing copper, comprising the step of:
 1 to 10 mass % of copper powder and titanium alloy powder which contains at least aluminum and vanadium are pressed and formed while being heated so as to form a dense compact. 
 
     
     
         5 . The method for production of the α+β or β titanium alloy according to  claim 4 , wherein a temperature in the pressing and forming while being heated (Tw(° C.)) is in the following range:
   ( Td− 100° C.)< Tw <( Td+ 100° C.)
 
 Td(° C.) being β transformation temperature of titanium alloy that is pressed and formed. 
 
     
     
         6 . The method for production of the α+β or β titanium alloy according to  claim 4 , wherein the titanium alloy powder is produced from raw titanium alloy, and the titanium alloy contains at least one selected from molybdenum, iron, chromium, and tin.