Duplex Stainless Steel
Duplex Stainless Steels Available at Mega Mex
Duplex Stainless Steel Overview
Duplex Stainless Steels, also referred to as austenitic-ferritic stainless steels, are a family of grades with about equal proportions of ferrite and austenite. These steels have a duplex microstructure which contributes to their high strength and high resistance to stress corrosion cracking. Due to their high content of chromium, nitrogen and molybdenum, duplex steels offer good resistance to local and uniform corrosion. Duplex stainless steels have good weldability.
Today, modern duplex stainless steels can be divided into three groups:
- Lean Duplex such as LDX2101
- Standard Duplex such as 2205, the work-horse grade accounting for more than 80% of duplex usage
- Super Duplex such as Ferralium 255, Zeron 100 and 2507
Of the duplex grades, duplex 2205 is the most widely used. However, the super duplex steels like Zeron® 100 and 2507 are excellent for servicing severe corrosive environments, such as offshore and marine applications. Lean duplex 2101 is available as an economic alternative to 300 series stainless steels.
What are the Characteristics of Duplex Stainless Steels®?
- Very good resistance to uniform corrosion
- Very good resistance to pitting and crevice corrosion
- High resistance to stress corrosion cracking and corrosion fatigue
- High mechanical strength
- Good sulfide stress corrosion resistance
- Good abrasion and erosion resistance
- Good fatigue resistance high energy absorption
- Low thermal expansion
- Good weldability
In what Applications are Duplex Stainless Steels® used?
- Oil and gas equipment
- Offshore technology
- Seawater desalination plants
- Chemical industry, especially when handling chlorides
- Flue-gas cleaning
- Pulp and paper industry
- Cargo tanks and pipe systems in chemical tankers
- Firewalls and blast walls on offshore platforms
- Storage tanks
- Pressure vessels, reactor tanks, and heat exchangers
- Rotors, impellers and shafts