Titanium alloys consist of a combination of titanium and other chemical elements, such as aluminum or tin. Such metallic alloys are lightweight, corrosion resistant, and possess high strength-to-weight ratios. Due to these qualities, titanium alloys have been used in a variety of applications, including power generation equipment, marine hardware, and chemical processing.
While there are several types of titanium alloys, the most commonly used alloy is the titanium 6Al-4V alpha-beta alloy. It is a two-phase, a + b structure with aluminum as the alpha stabilizer and vanadium as the beta stabilizer. Titanium 6Al-4V applications include: compressor blades, discs, and rings for jet engines; rocket engine cases; and helicopter rotor hubs. The metals engineering company, Richard Metals, used Ti-6AI-4V-Eli (extra low interstitial) to create the escape mechanism for NASA’s Ares Orion rocket. It is also the grade of alloy most commonly used for thick-walled highly-stressed parts, such as the Japanese “Shinkai” for taper stress joints. These alloys are available in plate, sheet, bar, or forged billet form.