Steel grades

Note that an increasing number of national European standards (DIN, AFNOR, UNE, UNI, etc.)

This task is carried out by the Comité Européen de Normalisation (CEN) (European Committee for Standardization).

For some application designations another letter is included before the property value, this number is used to indicate any special requirements or conditions.

So S355 has a minimum yield strength of 355 MPa for the smallest thickness range covered by the relevant standard – i.e.

The most common additional symbols are the impact and temperature codes for structural steels, category 1 - Sxxx.