Ti-Nb-Zr Alloy

Abstract

An object of the present invention is to develop a shape memory and superelastic alloy that does not contain nickel, and has superelasticity and shape memory properties even if being subjected to heat treatment in spite of high biocompatibility, moreover having high cold workability. The Ti—Nb—Zr base alloy is comprising an alloy composition consisting of 40 to 60 wt % Ti, 18 to 30 wt % Nb, 18 to 30 wt % Zr, and 0.77 to 3.7 wt % at least one metal additional element selected from Al, Sn, In and Ga. The Ti—Nb—Zr base alloy is a practical alloy in which the principal components form a strong and dense oxidation film to exhibit high biocompatibility, and also the alloy has superelasticity and shape memory properties, high cold workability, and high low-temperature properties.

1 . A Ti—Nb—Zr base alloy comprising:
 an alloy composition consisting by weight of 40 to 60 percent Ti, 18 to 30 percent Nb, 18 to 30 percent Zr; and   0.77 to 3.7 percent at least one metal additional element selected from Al, Sn, In and Ga.   
     
     
         2 . A method for manufacturing a Ti—Nb—Zr base alloy, comprising:
 subjecting an alloy having an alloy composition consisting by weight of 40 to 60 percent Ti, 18 to 30 percent Nb, 18 to 30 percent Zr, and 0.77 to 3.7 percent at least one metal element selected from Al, Sn, In and Ga to cold working of 50% or more, and   subjecting the alloy to solution heat treatment.