Introduction Ti-6Al-4V, Grade 5 alloy (UNS R56400) is the most widely used titanium grade. It is a two-phase α+β titanium alloy, with aluminum as the alpha stabilizer and vanadium as the beta stabilizer. This high-strength alloy can be used at cryogenic temperatures of about 800°F (427°C). Ti-6Al-4V, Grade 5 alloy is used in the annealed condition and in the solution-treated and aged condition. Some applications include compressor blades, discs, and rings for jet engines; air-frame and space capsule components; pressure vessels; rocket engine cases; helicopter rotor hubs; fasteners; critical forgings requiring high strength-to-weight ratios. This alloy is produced by primary melting using vacuum arc (VAR), electron beam (EB), or plasma arc hearth melting (PAM).
Standard ASTM B348 – Bars, Forgings, and Forging Stock (Annealed) ASTM B348 – Bars, Forgings (Solution treated and aged) ASTM B348 – Bars, Forgings (Annealed, Heat Treatable)
Material Properties
Forge-ability
Mach-inability: the alloy can be machined using practices for authenticating steels with slow speeds, heavy feeds, rigid tooling and large amounts of non-chlorinated cutting fluid.
Weld-ability: the alloy benefits from good weld-ability in the annealed condition or the solution and partially aged condition, with aging completed during the post-weld heat treatment. Precautions must be taken to prevent oxygen, nitrogen, and hydrogen contamination. Fusion welding can be done in inert gas-filled chambers or using inert gas welding of the molten metal and the adjacent heated zones using a trailing shield. Spot, seam, and flash welding can be performed without resorting to protective atmospheres.