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Ti6Al-4V is the most widely used of all the alpha-beta titanium alloys. It may be heat treated for high strength in welded construction at service temperatures through 600°F. Hardenability is limited and sections over about one inch may not develop full properties.
Applications
Typical Applications for the titanium alloy Ti 6Al-4V include:
- Turbine blades, discs and rings
- Aircraft structural components
- Fasteners
- Medical and dental implants
- Hand tools
- Sporting equipment
Composition of Ti6Al-4V
The composition range for Ti6Al-4V is provided in table 1.
Table 1. Composition of titanium alloy Ti6Al-4V.
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Aluminum
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5.50
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6.75
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Vanadium
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3.50
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4.50
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Carbon
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-
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0.08
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Nitrogen
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-
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0.05
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Oxygen
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-
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0.20
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Hydrogen
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-
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0.0125
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Iron
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-
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0.30
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Yttrium
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-
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0.005
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Others, each
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-
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0.10
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Other, total
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-
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0.40
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Titanium
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remainder
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Specifications
The various forms of Ti6Al-4V are covered by the following standards:
- UNS R56400 W.Nr. 3.7164/5
- AMS 4911 Sheet, strip, and plate, annealed
- AMS 4928 Bars, wire, forgings & rings, annealed, heat treatable
- AMS 4967 Bars, wire, forgings & rings, annealed, heat treatable
- MIL-T-9047 Bars and reforging stock
- MIL-T-81556 Extruded bars and shapes
- MIL-F-83142 Forgings
- ASTM B 265, Strip, sheet and plate Grade 5
- ASME SB-265
- ASTM B 348, Bar, Billet Grade 5
- ASME SB-348
- ASTM B 861, Seamless pipe Grade 5
- ASME SB-861
Heat Treatments
Annealing bar and forgings for maximum ductility is done at 1275-1325°F 2 hours furnace cool. Solution treated and aged condition is:
For sheet, 1675-1725°F 5 to 25 minutes, water quench. Age 975°F 4 to 6 hours, air cool.
For bars and forgings, 1675-1725°F 1 hour, water quench. Age 975-1025°F 3 hours, air cool.
For increased fracture toughness, but lower tensile strength, precipitation treat (overage) 1150-1250°F
4 hours, air cool.
Stress-relief annealing is commonly 1000-1200°F
1/2- 4 hours, air cool.
Physical Properties of Titanium Ti6Al-4V
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Density:
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0.160 lb/inch3
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Melting Range:
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2929-3020°F
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Beta Transus Nominal:
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1825±25°F
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Thermal Properties of Titanium Ti6Al-4V
The thermal properties of Ti6Al-4V are summarised in table 2.
Table 2. Thermal properties of titanium alloy Ti6Al-4V.
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RT
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-
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4.0
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16.7
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200
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5.3
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4.3
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16.0
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400
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5.4
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5.2
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15.0
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600
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5.5
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.1
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14.0
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Typical Mechanical Properties of Titanium Ti6Al-4V
The mechanical properties titanium alloy Ti6Al-4V, specified, AMS 4911, annealed sheet & plate are provided in table 3.
Table 3. Typical mechanical properties of Ti6Al-4V.
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>0.025 ≤ 0.063
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134
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126
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8
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>0.063 ≤0.1874
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134
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126
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10
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>0.1874 ≤ 4.000
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130
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120
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10
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Typical Range, Room Temperature Bar Tensile Properties
Table 4. Range in properties as a function of heat treatment for Ti6Al-4V
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Anneal 1300°F Air Cool
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138-155
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128-147
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15-20
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38-51
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Anneal 1300°F Solution anneal 1750°F Age 1000°F
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150-172
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137-156
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15-17
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41-46
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Typical Tensile Strength and Fracture Toughness
Table 5. Typical tensile strength and fracture toughness, various heat treatments for flat-rolled products (MCIC-HB-02 1985 reprint) for Ti6Al-4V
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Annealed (Continuously)
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143
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178
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Rolled Sheet
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142 (transversea)
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140 (transversea)
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Beta Annealed
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131
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134
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Beta STA 1250°Fb
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128
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150
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Beta STA 1000°Fb
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143
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120
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STA 1250°Fc
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137
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105
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STA 1000°Fc
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159
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80
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(a) Directional variations
(b) Beta heat treated followed by solution treating and overaging 1250°F, or aging 1000°F
(c) Solution treating and overaging 1250°F, or aging 1000°F
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