Titanium Grade 6

FORMS WE CAN PROVIDE

Ti Gr6 Sheet/Plate
Ti Gr6 Rod/Bar
Ti Gr6 Tube/Pipe
Ti Gr6 Wire

Titanium Grade 6

Titanium Grade 6 is a medium-strength α-type single-phase titanium alloy, containing 5% α-stabilizing element aluminum and 2.5% neutral element tin. The alloy cannot be strengthened by heat treatment, and is usually used in an annealed state, and has good fracture toughness at room temperature and high temperature. Its process plasticity is low, and sheet forming should be carried out in a heated state, and it is characterized by better heat resistance strength. The alloy also has good welding performance and is suitable for welding processes of tungsten electrodes and metal electrodes under the protection of inert gas.
Titanium Grade 6 can be used to make parts such as casings and wall panels. The long-term working temperature of this alloy can reach 500℃, and the short-term working temperature can reach 800℃. The TA7ELI alloy with low interstitial impurity elements is suitable for use at low temperatures. The semi-finished products produced include plates, bars, cakes and ring parts, which can also be used to produce castings.

Bending properties
Form δ/mm State Sampling direction α(D=6d)/(º) α(D=3δ)/(º)
Sheets 0.8～2.0 Annealing LT 20 ≥50

Titanium Grade 6 chemical composition (mass fraction) %

Grade Alloy Element Impurities≤
Ti Al Sn Fe Si C N H O Other Element
Single Total
TA7 Balance 4.0~6.0 2.0~3.0 0.5 – 0.1 0.05 0.015 0.2 0.1 0.4
TA7ELI Balance 4.5~5.75 2.0~3.0 0.25 – 0.05 0.035 0.0125 0.12 0.05 0.3
TA7(Welding wire) Balance 4.0~6.0 2.0~3.0 0.45 – 0.05 0.05 0.012 0.15 0.1 0.4

Forms of Titanium Grade 6 We Can Provide

Physical and Chemical Properties of Ti-5Al-2.5Sn

1. Density ρ=4.42g/cm3
2. Melting temperature range: 1540~1650℃

3. Thermal conductivity

Thermal conductivity
θ/℃ 20 100 200 300 400 500 600 700 800
λ/W·m-1·K-1 8.8 9.6 10.9 12.2 13.4 14.7 15.9 17.2 18.4

4. Specific heat capacity

Specific heat capacity
θ/℃ 100 200 300 400 500 600 700 800
c/J·kg-1·K-1 503 545 566 587 628 670 712 796

5. Coefficient of linear expansion

Coefficient of linear expansion
θ/℃ 20～100 20～200 20～300 20～400 20～500 20～600 20～700 20～800 20～900
α/10-6·K-1 8.5 8.9 9.1 9.3 9.5 9.6 9.7 10.1 10.5
θ/℃ 100～200 200～300 300～400 400～500 500～600 600～700
α/10-6·K-1 9.3 9.7 10 10.3 10.5 11

6. Electrical properties Resistivity

Resistivity
θ/℃ 20 100 200 300 400 500 600
ρ/μΩ·m 1.38 1.69 1.75 1.8 1.84 1.87 1.88
7. Magnetic properties
non-magnetic
8. Antioxidant properties
Similar to industrial pure titanium and Ti Gr5
9. Corrosion resistance
Ti-5Al-2.5Sn is stable under atmospheric conditions and in seawater. Compared with Ti Gr5, this alloy is more sensitive to hot salt stress corrosion. The alloy will produce stress corrosion when it is exposed to 316°C and 207MPa stress for 100h in an environment heavily covered by artificial sea salt.

Phase transformation and microstructure of Ti-5Al-2.5Sn

Phase transition temperature

The transformation temperature of β↔α+β phase is 1040~1090℃;
The transformation temperature of α↔α+β phase is 930~970℃

Microstructure

The equilibrium structure of the alloy below the α↔α+β transformation temperature (about 950°C) is single-phase α; when the alloy is rapidly cooled from the upper part of the α+β phase region (for example, 1010°C), α’ and a small amount of α can be obtained phase; rapid cooling from the β phase region can obtain the α phase. During the annealing process, the α’ phase gradually decomposes and transforms into the α phase.

Manufacturing process and properties of Ti-5Al-2.5Sn

Melting and casting process of Ti-5Al-2.5Sn

The ingot should be smelted in a vacuum consumable electric arc furnace for more than two times. Alloying elements Al and Sn are added in the form of Al-Sn intermediate. The welding of the consumable electrode adopts the argon shielded plasma welding method, and the use of argon tungsten arc welding is strictly prohibited.

Heat treatment system of Ti-5Al-2.5Sn

1) Annealing
Plate: 700~850℃, 10~120min, air cooling Bars and forgings: 700~850℃, 1~4h, air cooling
2) Stress relief annealing
540~650℃, 15~360min, air cooling or furnace cooling. Casting: 600~800℃, 1~4h, air cooling or furnace cooling.

Thermal deformation process

When the final fire deformation is carried out below the β transformation temperature, the deformation amount should be greater than 25%~40% to obtain good mechanical properties. If reheating is required in the future (such as thermal correction), it should be carried out at a temperature lower than 90 °C below the β transition temperature.
Thermal deformation process specification of Ti-5Al-2.5Sn
Forging type Heating temperature/℃ Final forging temperature/℃  First fire deformation/%
Ingot blooming 1180 ≥900 30～50
Blank pre-deformation 1100 ≥850 40～70
Forging hammer die forging 1020～1100 ≥900 40～70
Press die forging 1020 ≥850 40～70

Deformation resistance of Ti-5Al-2.5Sn under different deformation rates
Deformation temperature The maximum deformation resistance of the following deformation rate (s-1)/MPa
10 10 1 10
800 222 320 365 452
900 205 262 285 313
1000 80 93 105 117
1100 35 59 62 80

Tensile properties of Ti-5Al-2.5Sn at heat distortion temperature
Form d/mm State Sampling direction θ/℃ σb/MPa δ5/% ψ/%
Rods 22 Annealing L 700 252 86.2 82.2
800 160 140.8 95.6
850 121 140 94
900 88 170 96.5
1000 35 78 63

Application of Titanium Grade 6

Using Titanium Grade 6 die forgings and ring parts made of engine adapter, front brake housing, sealing ring housing, as well as plate hot-press forming linings, bracket seats and wall panels and other parts have been used in the aviation industry. Because the alloy has excellent corrosion resistance, it is especially suitable for manufacturing ship parts.