Titanium Alloy Ti6Al-4V – Properties, Composition, Heat Treatments and Specifications from Super Alloys

Background

The Super Alloys management team are amongst the most experienced professionals in the market. Supported by professional metallurgists and technicians, Super Alloys not only provide access to the largest range of high-tec metals in Europe, but also access to the broadest range of expertise.

The unique combination of access to stock, expertise and rapid delivery reduces lead times and can eliminate costly production delays.

The Super Alloys range of materials includes:

•         Titanium Alloys

•         Nickel Alloys

•         Steels

Titanium Ti6Al-4V

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.

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

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.

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.

Typical Range, Room Temperature Bar Tensile Properties

Table 4. Range in properties as a function of heat treatment for Ti6Al-4V

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

(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

Source: Super Alloys

For more information on this source please visit Super Alloys.