Six different titanium alloys are contained in the F-22 Raptor airframe, in both cast and wrought forms. Each alloy is chosen for its particular properties suite, usually with some dominant characteristic dictating the particular product form, alloy composition, and heat treatment.

The F-22 air superiority fighter utilizes more titanium than any other United States Air Force aircraft, over 9000 lb, or approximately 42% by weight. Stringent F-22 performance requirements led to the extensive application of titanium alloys. For example, high cyclic loads under harsh environmental conditions require the airframe and critical systems to have outstanding resistance to fatigue, high temperatures, and environmental effects. Titanium alloys offer the best combination of properties to meet these requirements.

The F-22 product mix consists of cast and wrought versions of six different alloys and multiple heat treatments. The titanium alloys on the F-22 include:

* Ti-6A1-4V (Ti-6-4), standard cast and wrought, and ELI wrought grades

* Ti-6A1-2Sn-2Zr-2Cr-2Mo-0.2Si (Ti-6-22-22)

* Ti-6A1-2Sn-4Zr-2Mo-0.lSi (Ti-6242)

* Ti-10V-2Fe-3A1 (Ti-10-2-3)

* Ti-15V-3Cr-35n-3A1 (Ti-15-3)

* Ti-3A1-2.5V (Ti-3-2.5)

[Note that all of these titanium alloys are found in the CINDAS LLC databases.]

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Used with permission of one of the authors, Henry R. Phelps.