γ+α2型Ti-Al系金属間化合物の微視的組織と常温延性に及ぼす加工熱処理条件とAl量の影響
1994 年 80 巻 1 号 p. 83-88
詳細
1994 年 80 巻 1 号 p. 83-88
Thermo-mechanical treatment conditions have been investigated on γ+α2, type titanium aluminides to obtain a uniformly fine grained structure which is expected to exhibit a high ductility at room temperature. A higher working reduction, followed by a heat treatment at the temperature at which volume fractions of the γ and α phases are equal to each other is required to obtain the fine duplex microstructure consisting of the equi-axed γ and lamellar grains. The room temperature tensile elongation in such fine duplex microstructures strongly depends on the volume fraction of the α2 phase. A higher Al content results in a high tensile elongation, especially 7.8% in the stoichiometric composition where small amount of α2 are contained. The maximum elongation of 7.8% is substantially higher than those formerly reported.
