Steel its tensile strength and make the austenite form of the iron-carbon solution more stable, chromium increases hardness and melting temperature, and vanadium also increases hardness while making it less prone to metal fatigue. To inhibit corrosion, at least 11% chromium is added to steel so that a hard oxide forms on the metal surface; this is known as stainless steel. Tungsten slows the formation of cementite, keeping carbon in the iron matrix and allowing martensite to preferentially form at slower quench rates, resulting in high speed steel. On the other hand, sulfur, nitrogen, and phosphorus are considered contaminants that make
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