Titanium alloys

This heat treatment process is carried out after the alloy has been worked into its final shape but before it is put to use, allowing much easier fabrication of a high-strength product.

These are molybdenum, vanadium, niobium, tantalum, zirconium, manganese, iron, chromium, cobalt, nickel, and copper.

Some of the beta titanium alloys can convert to hard and brittle hexagonal omega-titanium at cryogenic temperatures[11] or under influence of ionizing radiation.

[12] The crystal structure of titanium at ambient temperature and pressure is close-packed hexagonal α phase with a c/a ratio of 1.587.

At about 890 °C, the titanium undergoes an allotropic transformation to a body-centred cubic β phase which remains stable to the melting temperature.

Molybdenum, vanadium, tantalum, niobium, manganese, iron, chromium, cobalt, nickel, copper and silicon are beta stabilizers.

Oxide precipitates offer some strength (as discussed above), but are not very responsive to heat treatment and can substantially decrease the alloy's toughness.

Titanium and its alloys are used in airplanes, missiles, and rockets where strength, low weight, and resistance to high temperatures are important.

[14][15][16] Since titanium does not react within the human body, it and its alloys are used in artificial joints, screws, and plates for fractures, and for other biological implants.

Reduced interstitial elements oxygen and iron improve ductility and fracture toughness with some reduction in strength.

[36] The Ti-3Al-2.5V alloy, which consists of 3% aluminum and 2.5% vanadium, was designed for low-temperature environments, maintaining high toughness and ductility even under cryogenic conditions in space.

Titanium alloys have been extensively used for the manufacturing of metal orthopedic joint replacements and bone plate surgeries.

They are normally produced from wrought or cast bar stock by CNC, CAD-driven machining, or powder metallurgy production.

Traditional powder metallurgy methods are also more material efficient, yet acquiring fully dense products can be a common issue.

[39] With the emergence of solid freeform fabrication (3D printing) the possibility to produce custom-designed biomedical implants (e.g. hip joints) has been realized.

[40] While it is not applied currently on a larger scale, freeform fabrication methods offers the ability to recycle waste powder (from the manufacturing process) and makes for selectivity tailoring desirable properties and thus the performance of the implant.

Key applications include engine components like valves and connecting rods, exhaust systems, suspension springs, and fasteners.