Abstract
Cost, availability, and performance are all driving factors in material selection. Duplex stainless steels have long been a point of interest to the pulp and paper industry and biomass conversion due to lean alloying elements and good corrosion resistance. The caution with using duplex stainless steels is in understanding relative price compared to similar austenitic alloys and realistic availability. This paper reviews decisions to be made when considering a duplex stainless steel in today’s market. Lean duplex has been successful in replacing 300 series austenitic stainless in storage tanks where the only product forms used are plate and weld wire. In contrast, it may not be as easy or economical to switch a piping system or heat exchanger from 316L to a lean duplex. In situations where certain product forms are not available, a combination of lean duplex and 2205 duplex can be used. This story of supply and demand is not a new phenomenon. Even 2205 duplex was once a “new” grade, but is now readily available from many suppliers in nearly every product form at an economical price. Some positive experiences are when an end user finds a need (demand) and works with a supplier to develop the product and increase availability (supply). These are growing pains that need to be understood or users will either waste money or never develop new products.
