What Does Duplex Stainless Steel Mean?
Duplex stainless steel is a type of stainless steel that is composed of grains of two types of stainless steel material, austenitic and ferritic. The word "duplex" refers to the two-phase microstructure of ferritic and austenitic steel grains. The ferritic and austenitic stainless steel grades have approximately equal proportions (i.e., 50% each) in duplex stainless steel.
Duplex stainless steel offers high mechanical strength and excellent corrosion resistance properties.
Corrosionpedia Explains Duplex Stainless Steel
Duplex stainless steel is considered an alternative to the expensive nickel alloys and high alloy austenitic stainless steel materials used in the most demanding applications.
Some benefits of duplex stainless steel include:
- Two times stronger than ferritic or austenitic stainless steel grades
- Higher toughness and ductility
- Shows very good resistance from stress corrosion cracking
- Cheaper than the austenitic stainless steel material because the nickel and molybdenum alloy content is less in duplex stainless steel than austenitic stainless steel