1, Gr6 and Gr6 ELI alloys are typical α-type alloys with nominal composition of Ti-5Al-2.5Sn. Al and Sn stabilize α and strengthen solution.
2. Gr6 alloy cannot be strengthened by heat treatment, but can only be strengthened by recrystallization annealing. The starting temperature of recrystallization is 580℃, and the β-phase transition point is about 1020~1030℃. The recrystallization annealing temperature of sheet metal is 700~750℃, and that of bar and forgings is 800~850℃. The stress relief annealing temperature is 550~600℃.
3. Gr6 alloy has medium strength, good creep resistance and thermal stability. The long-term working temperature can reach 450℃, the short-term working temperature can reach 800~850℃.
4. Gr6 alloy has good low temperature property and welding property. With the decrease of temperature, the strength increases and the plasticity decreases slightly. TA7ELI alloy with low interstitial element content still maintains good plasticity at -250℃. It is commonly used as ultra-low temperature and high pressure vessel, and is mostly supplied with plate and bar.
5, Gr6 alloy process plasticity is low, sheet stamping forming must be carried out in the heating state, generally heated to about 700℃ to have enough process molding.
Composition and properties of Gr6 alloy
Low temperature properties of Gr6 alloy