ASTM A789 UNS S32550 Super Duplex Stainless Steel Tubes
ASTM A789 UNS S32550 Super Duplex Stainless Steel Tubes are engineered for tough industrial environments where high strength, superior corrosion resistance, and excellent durability are essential. UNS S32550 is a super duplex grade that offers a balanced microstructure of ferrite and austenite, delivering enhanced mechanical strength along with exceptional resistance to pitting, crevice corrosion, and chloride-induced stress corrosion cracking.
These tubes perform reliably in aggressive media, making them ideal for offshore platforms, desalination plants, chemical processing, and high-pressure industrial systems. With its combination of mechanical performance and corrosion resistance, UNS S32550 is a preferred material for engineering applications requiring long-lasting service life.
Key Features
- Excellent pitting and crevice corrosion resistance
- High mechanical strength suitable for heavy-duty applications
- Superior resistance to stress corrosion cracking
- Performs exceptionally in chloride-rich and marine environments
- Low thermal expansion and high thermal conductivity
- Long service life with minimal maintenance
Equivalent Grade
| Standard |
Grade |
| UNS |
S32550 |
| EN / DIN |
1.4507 |
| WNR |
1.4507 |
| AFNOR |
Z3CD25.06Az |
| Trade Name |
Ferralium 255 |
ASTM A789 UNS S32550 Chemical Composition
| Element |
Percentage (%) |
| Chromium (Cr) |
24.0 – 27.0 |
| Nickel (Ni) |
4.5 – 6.5 |
| Molybdenum (Mo) |
2.0 – 3.0 |
| Copper (Cu) |
1.5 – 2.5 |
| Manganese (Mn) |
≤ 1.5 |
| Silicon (Si) |
≤ 1.0 |
| Nitrogen (N) |
0.20 – 0.35 |
| Carbon (C) |
≤ 0.04 |
| Phosphorus (P) |
≤ 0.04 |
| Sulfur (S) |
≤ 0.02 |
| Iron (Fe) |
Balance |
ASTM A789 UNS S32550 Mechanical Properties
| Property |
Value |
| Tensile Strength |
≥ 750 MPa |
| Yield Strength (0.2% Proof) |
≥ 550 MPa |
| Elongation |
≥ 25% |
| Hardness |
≤ 310 HB |
Physical Properties
| Property |
Value |
| Density |
7.80 g/cm³ |
| Thermal Conductivity |
15 W/m·K |
| Electrical Resistivity |
0.90 µΩ·m |
| Modulus of Elasticity |
200 GPa |
| Melting Range |
1350 – 1450°C |
Types of Grade UNS S32550 Tubes
- Seamless Super Duplex Tubes
- Welded Super Duplex Tubes
- ERW Tubes
- EFW Tubes
- Heat Exchanger Tubes
- Hydraulic & Instrumentation Tubes
Application
- Offshore Oil & Gas Structures
- Marine & Seawater Systems
- Desalination Plants
- Chemical & Petrochemical Processing
- Pulp & Paper Industries
- High-Pressure Heat Exchangers
- Power Generation Units
- Pressure Vessels & Boilers
Reviews
There are no reviews yet.