What is duplex stainless steel and how it is used
Duplex stainless steels are a branch of stainless steel, known to be one of the most enduring steels. These steels are named “duplex” or also “austenitic-ferritic” since they have a two-phase microstructure of austenite and ferrite. Duplex stainless steel is a material that is used in different industries thanks to its excellent corrosion resistance. However, there are different duplex grades so the characteristics of duplex stainless steel might vary a little according to the chemical composition, that is set during the process of its production. In fact, nowadays it’s possible to find several duplex grades, from lean duplex stainless steel to hyper duplex stainless steel.
The applications of this material
Duplex stainless steels are mostly used because of their mechanical properties and for their high resistance to corrosion. All duplex steels have high strength and ductility, that’s why this material is used in many industrial fields. Let’s see where duplex stainless steel is required and utilized:
- Desalination
Desalinating seawater is a complex process that requires evaporators. Duplex stainless steel is the material employed for the fabrication of those machines, since it is resistant to corrosion and has a high strength.
2. Production of paper
The process of paper production requires bleach and some other corrosive substances. They are contained in special tanks, which are produced using duplex stainless steels. It is because of its chemical composition and properties that it is the best material for this purpose.
- Architecture
With its mechanical strength and great resistance to corrosion, this material is widely used in the architecture environment and, in general, construction. Its structure and composition allow the usage of thinner sections and profiles, which are perfect for weight reduction. Bridges are the perfect example since their weight can’t be too high and it is usually in contact with seawater.
- Storage of food and drink
This material finds a good area of use even in the food industry. The employment of thinner layers for the storage of food and drinks is possible thanks to the characteristics of this type of steel.
- Gas and Oil
Manifolds, pumps and piping are some of the components used in the gas and oil industry. Such tools need specific properties in order to be used safely and efficiently. For the manufacture of those, duplex stainless steel is the proper material that meets all the requirements.
Properties of Duplex Stainless Steel
Duplex stainless steel displays peculiar properties that make it valuable in certain type of applications. Its components, considered singularly, might show better applications than other types of steel. It’s the combination of those components that contributes to generate a profitable balance at the moment of producing the tools and the machines previously mentioned. Great corrosion resistance, mechanical strength, and stress corrosion cracking (known as SCC) resistance are some of the properties of duplex stainless steel. Duplex stainless steels are ideal for producing lighter structures in weight because of the lower amount of steel involved in the production. Moreover, it has a good weldability, little heat expansion and good resistance to pitting.
