High strength, high ductility titanium-alloy and process for producing the same

摘要

PCT No. PCT/JP96/01078 Sec. 371 Date Feb. 7, 1997 Sec. 102(e) Date Feb. 7, 1997 PCT Filed Apr. 19, 1996 PCT Pub. No. WO96/33292 PCT Pub. Date Oct. 24, 1996A high strength, high ductility titanium alloy comprising O, N and Fe as strengthening elements and the balance substantially Ti, the contents of the strengthening elements satisfying the following relationships (1) to (3): (1) from 0.9 to 2.3% by weight of Fe, (2) up to 0.05% by weight of N, and (3) an oxygen equivalent value Q, which is defined by the formula mentioned below, of 0.34 to 1.00 Q=[O]+2.77[N]+0.1[Fe]wherein [O] is an oxygen content (% by weight), [N] is a nitrogen content (% by weight) and [Fe] is an iron content (% by weight), the titanium alloy having a tensile strength of at least 700 MPa and an elongation of at least 15%. Part of Fe may be replaced with Cr and/or Ni. Fe, Cr and Ni may be introduced from a carbon steel or stainless steel, or they may be introduced from sponge titanium containing these elements.