The chemical composition of this category of steels, also called biphasic, allows a mixed structure of austenite and ferrite to be obtained with unique corrosion resistance characteristics, especially to corrosion under voltage and to marine corrosion. Thanks to these characteristics and to the high mechanical strength, which can be obtained with hardening and cold deformation, these steels are commonly used in offshore platforms, and in any case where the action of salt and corrosive agents is particularly accentuated. They are magnetic, can generally be welded and cannot be tempered. These are therefore products with a particularly high level of performance, whose development is still underway and whose applications have yet to be fully explored.
