Stainless steel film of chromium oxide by reaction with the oxygen in air and even the small amount of dissolved oxygen in water. This passive film prevents further corrosion by blocking oxygen diffusion to the steel surface and thus prevents corrosion from spreading into the bulk of the metal. This film is self-repairing if it is scratched or temporarily disturbed by an upset condition in the environment that exceeds the inherent corrosion resistance of that grade. However, stainless steels may suffer uniform corrosion when exposed to acidic or basic solutions. Whether a stainless steel corrodes depends on the kind and concentration of
Duplex stainless steel are higher. This can be a great advantage when strength is important. This is the case in bridges, pressure vessels or tie bars. Chemicals composition of grades from EN 10088-1 (2014) Standard are given in the table below: Mechanical properties from European Standard EN 10088-3 (2014) (for product thickness below 160mm): <nowiki>*</nowiki>for thickess ≤ 5 mm The minimum yield stress values are about twice as high as those of austenitic stainless steels. Duplex grades are therefore attractive when mechanical properties at room tempearature are important because they allow thinner sections. Duplex stainless steel Duplex stainless steels is the most recent