Titanium is able to achieve amazing changes in microstructures by variations in thermomechanical processing, and therefore a broad range of properties and applications can be served with a relatively small number of titanium grades. Consequently, there are about 50 main titanium grades that are designated and currently used, although only a couple of dozen are readily available commercially.
The US ASTM titanium standards recognize about 40 main titanium grades, of which Grades 1 through 4 are commercially pure (unalloyed). The titanium grades covered by ASTM and other alloys are also produced to meet Aerospace and Military specifications (SAE-AMS, MIL-T), as well as ISO titanium standards, Euronorm, GOST, and the Japanese JIS titanium standards. Although there is an overlap between these standards for titanium, they are not interchangeable. The Japanese Titanium Society, in its efforts to achieve a more global approach to titanium standard, has made representations of unified systems of specifications.
However, the major problem with titanium standards is not a lack of standards defined by standards development organizations (SDOs), but the detailed, individual specifications by the aerospace companies which limit production runs. Each aerospace company has its own specification which includes processing routes. Consequently, a process route which is allowed by one company may not be allowed by another.
This results in small batch production. Overproduction can be stored but can only be used by a company which agrees the specification, and the material is probably over-qualified for industrial use having gone through the very detailed quality assurance requirements of the aerospace industry. Similarly, the high proportion of material which results as scrap must be carefully separated in order to provide the detailed pedigree which is required by the aerospace companies.
The KEY to METALS database brings these and many other global standards together into one integrated and searchable database. Quick and easy access to
the mechanical properties, chemical composition, cross-reference tables, and
more provide users with an unprecedented wealth of information. Click the buttons below to learn more from the Guided Tour or to test drive the KEY to METALS database.