Duplex Steel pipes have two structural phases viz. Austenitic and Ferritic. Mechanical properties of Duplex Steels are outstanding. Also, the corrosion resistance properties in these pipes is excellent.
When compared to regular austenitic and ferritic steel grades, Duplex Steels are stronger. In comparison to only ferritic steels the ductility and toughness of Duplex steel pipes is much better. Chloride pitting and crevice corrosion is not a problem for these pipes as the nitrogen, chromium and molybdenum content make it highly resistant to it. These duplex steel pipes are immune to stress-corrosion cracking. Duplex Steel pipes are added with less amounts of nickel and molybdenum in comparison to other austenitic grades, making them highly cost effective. The increased tensile strength helps in altering the sectional thickness of these pipes against normal austenitic steels. Duplex Steel pipes find usage in many applications such as processing plants, brewing tanks, hot water tanks and more. This is due to the stress-corrosion cracking resistance of the steel. The relatively low costs, general corrosion resistance and higher strength make these duplex steel pipes more popular.