And so on (+) of the axial fine grain production manner null of the titanium alloy material which possesses 2 phase

摘要

PURPOSE:To obtain easily the titled Ti alloy material excellent in strength and ductility by performing successively working more than a specified proportion in a beta region and a (alpha+beta) two-phase region of each prescribed temp. range, thereafter performing the keeping treatment, cooling a Ti alloy in the prescribed cooling velocity and performing the aging treatment. CONSTITUTION:A Ti alloy material is subjected to =40% draft hot rolling in the beta region of 1,000-1,100 deg.C such as shown in a figure (b) and furthermore =40% draft hot rolling is performed in the (alpha+beta) two-phase region of 850-950 deg.C. The equiaxial fine grain structure is obtained by the second rolling. The Ti alloy material after the above-mentioned rolled treatment is subjected to the keeping treatment of 30min-2hr at its temp. or the temp. range up to 800 deg.C and cooled to 450-550 deg.C from its temp. in =5 deg.C/sec cooling velocity. The aging treatment up to maximum 20hr is performed at its temp. without cooling it to the room temp. from the above-mentioned temp. Thereby the Ti-6% Al-4% V alloy having the equiaxial fine grain (alpha+beta) two-phase structure is obtained.