Back in 1955, specification MIL-T-9046 was born, covering Titanium Sheet, Strip, and Plate. This specification tends to cause a lot of confusion for clients because it covers nearly 20 different types of titanium, and several conditions within some of the alloys. On top of that, during several revisions of the spec, a new alloy designation code was given to each type. We hope the following table and discussion helps to ensure procurement of the right type of titanium for your requirements.
The above table appears in the back of MIL-T-9046J (available for free download at http://assist.dla.mil), but we like our version better. *If you agree, you are welcome to email us at firstname.lastname@example.org and we will gladly share a copy.
Back to the good stuff. Specification MIL-T-9046 was cancelled in September 1999. Its last active revision was “J”, and the code designations for that revision are featured in the far right column of the above table. In the MIL-T-9046 cancellation notice, future acquisition was directed to SAE AMS-T-9046, which is also now cancelled. If your contract requires use of the superseding specification, refer to this discussion for help.
Since the MIL-T-9046 specification has been used for decades, often times a drawing will call out an old code such as “MIL-T-9046 Type 3 Comp C”. Using the table above, we can determine that “Type 3 Comp C” means the requirement is for 6Al-4V, and the drawing is pulling from an older revision of the specification, either Revision F or H. These days, it is unusual to procure material whose certifications will still use older revisions. Certifications would most likely display this requirement as “MIL-T-9046J AB-1”. Check with your Sales Rep if you have questions.
The code designations for Commercially Pure grades of titanium were established in the most unfortunate fashion. Under MIL-T-9046 Revision J, Commercially Pure Grade 1 titanium would now be referred to as “CP-4”, Commercially Pure Grade 2 titanium became “CP-3”, Commercially Pure Grade 3 titanium became “CP-2” and Commercially Pure Grade 4 titanium became “CP-1”. If you are unsure which grade you require, please contact us for help. Although the names sound similar, the differences between the grades are significant.