Many of us are familiar with the advantages of duplex stainless steel – higher strength, better fatigue properties, high resistance to chloride stress corrosion cracking, higher corrosion resistance in certain other media, and lower cost of alloying elements. The duplex alloys are “problem-solving alloys” for good reason, they have been successfully used in many places where carbon steels and standard austenitic alloys have failed.
Just like with the austenitic family, there are many different duplex alloys to choose from, with corrosion resistance varying from moderate with the lean duplex alloys to very high with the superduplex alloys.