Titanium alloy for golf club face

Abstract

An α+β-type titanium alloy which, has a high Young's modulus and strength-ductility balance is provided as a material for a face of a driver, iron, or other golf club. A titanium alloy having a high strength and high Young's modulus for a golf club face comprising, by mass %, 4.7 to 5.5% of Al, 0.5 to 1.4% of Fe, 0.03% or less of N, O which satisfies an [O] eq (oxygen equivalent value) of 0.25 to 0.34% calculated by formula (1), and a balance of Ti and unavoidable impurities. By adding Al, O, and N which cause solution strengthening of the α-phase and selecting the inexpensive Fe as the β-stabilizing element and suitably limiting the amounts of addition of these elements, it is possible to achieve a high strength and a high Young's modulus which satisfies the SLE rule without relying on cold working strengthening or aging strengthening heat treatment, and simultaneously obtain a large, good total elongation and a high strength-ductility balance. [O]eq=[O]+2.77[N]  formula (1)

1 . A titanium alloy having a high strength and high Young's modulus for a golf club face comprising, by mass %, 4.7 to 5.5% of Al, 0.5 to 1.4% of Fe, 0.03% or less of N, O which satisfies an [O]eq (oxygen equivalent value) of 0.25 to 0.34% calculated by formula (1), and a balance of Ti and unavoidable impurities.
   [O]eq=[O]+2.77[N]  formula (1)
   
       wherein [O] is the concentration of oxygen (mass %) and [N] is the concentration of nitrogen (mass %).