Ti-6Al-4V


Ti-6Al-4V, also sometimes called TC4 or Ti64, is an alpha-beta titanium alloy with a high strength-to-weight ratio and excellent corrosion resistance. It is one of the most commonly used titanium alloys and is applied in a wide range of applications where low density and excellent corrosion resistance are necessary such as e.g. aerospace industry and biomechanical applications.
Studies of titanium alloys used in armors began in the 1950s at the Watertown Arsenal, which later became a part of the Army Research Laboratory.

Chemistry

VAlFeOCNHYTiRemainder EachRemainder Total
Min3.55.5------------------
Max4.56.75.3.2.08.05.015.005Balance.1.3

Physical and Mechanical Properties

Ti-6Al-4V titanium alloy commonly exists in alpha, with hcp crystal structure, and beta, with bcc crystal structure, phases. While mechanical properties are a function of the heat treatment condition of the alloy and can vary based upon properties, typical property ranges for well-processed Ti-6Al-4V are shown below. Aluminum stabilizes the alpha phase, while vanadium stabilizes the beta phase.
Density, g/cm3Young's Modulus, GPaShear Modulus, GPaBulk Modulus,GPaPoisson's RatioYield Stress, MPa Ultimate Stress, MPa Hardness, Rockwell CUniform Elongation, %
Min4.4291044096.80.3188090036 5
Max4.512113451530.37920950--18

Ti-6Al-4V has a very low thermal conductivity at room temperature, 6.7 - 7.5 W/m·K, which contributes to its relatively poor machinability.

Heat Treatment of Ti-6Al-4V

Ti-6Al-4V is heat treated to vary the amounts of and microstructure of and phases in the alloy. The microstructure will vary significantly depending on the exact heat treatment and method of processing. Three common heat treatment processes are mill annealing, duplex annealing, and solution treating and aging.

Applications