UNS S32750, commonly known as super duplex 2507, is very similar to UNS S31803 duplex.The difference between the two is the higher chromium and nitrogen content of the super duplex, resulting in higher corrosion resistance and longer service life.
The content of chromium, nickel, molybdenum and manganese in the super duplex was 24% ~ 26%, 6% ~ 8%, 3% and 1.2%.Trace amounts of carbon, phosphorus, sulfur, silicon, nitrogen, and copper have also been found in the super duplex.Advantages are: good weldability and processing, high thermal conductivity, low thermal expansion coefficient, high corrosion resistance, fatigue resistance, pitting corrosion and gap corrosion resistance, stress corrosion cracking (especially chloride stress corrosion cracking), high energy absorption, high strength and corrosion resistance.
In essence, the duplex alloys are a compromise;compared with ordinary austenitic stainless steel, it has some ferrite resistance to stress corrosion cracking and many superior formability, and is more cost effective than high nickel alloy.
Industries that use Super Duplex include:
- Chemical
- Marine
- Oil and Gas production
- Petrochemical
- Power
- Pulp and Paper
- Water desalinization
Products partially or completely constructed of Super Duplex include:
- Cargo tanks
- Fans
- Fittings
- Heat exchangers
- Hot water tanks
- Hydraulic piping
- Lifting and pulley equipment
- Propellers
- Rotors
- Shafts
- Spiral wound gaskets
- Storage vessels
- Water heaters
- Wire
| Specifications and chemistry analysis | ||
| UNS | TYPE | CHARACTERISTICS |
| S32750 | SUPER DUPLEX | Higher chromium and nitrogen content in Super Duplex makes it superior in corrosion resistance and enables a longer lifespan than Duplex. |
Super duplex 2507 stainless steel pipe chemical composition:
| C≤ | Mn≤ | P≤ | S≤ | Si≤ | Cr | Ni | Mo | Cu≤ | N | M/NM |
| 0.03 | 1.2 | 0.035 | 0.02 | 0.8 | 24–26 | 6–8 | 3–5 | 0.5 | 0.24-0.32 | INQUIRE |
