Super Duplex Stainless Steel Round Bar
Super Duplex stainless 32750/32760 bars, is a mixed microstructure of austenite and ferrite in the same proportion (50/50) which has improved strength over ferritic and austenitic steel grades. Super duplex bar has a higher molybdenum and chromium content which gives the material greater corrosion resistance than standard duplex grades.
Chemical composition
GRADE |
ELEMENT |
CR |
C |
CU |
MN |
MO |
N |
NI |
P |
W |
Si |
---|---|---|---|---|---|---|---|---|---|---|---|
S32750/S32760 |
min |
24 |
– |
0.5 |
– |
3 |
0.24 |
6 |
– |
– |
– |
max |
26 |
0.03 |
1 |
2 |
5 |
0.35 |
8 |
0.35 |
0.03 |
1 |
Properties
Alloy 2507 is a super duplex stainless steel with chromium, molybdenum, and nickel addition that provides excellent resistance to chloride stress corrosion cracking, high thermal conductivity and a low coefficient of thermal expansion. The high chromium, molybdenum, and nitrogen levels provide excellent resistance to pitting, crevice, and general corrosion.
Mechanical Properties
Grade |
Tensile Strength |
Yield Strength |
Elongation |
Hardness, MAX |
---|---|---|---|---|
[MPA] |
[MPA] |
(% in 50mm) min |
HRB |
|
Super duplex |
750 |
550 |
25 |
290 |
Super duplex round bar has low carbon content and reduces the risk of carbide precipitation at the grain boundaries during heat treatment; therefore, the alloy is highly resistant to carbide-related intergranular corrosion.
Physical properties
Grade |
Density (g/cm3) |
Melting Range °C |
Elastic Modulus (GPa) |
Thermal Expansion coefficient (μm/m/°C) |
Thermal Conductivity (W/m.K) |
Specific Heat (J/Kg.K) |
Electrical Resistivity (μΩ.cm) |
---|---|---|---|---|---|---|---|
20°C |
|||||||
S32750/S32760 |
7.8 |
1350°C / 2460°F |
200 |
11.1 |
14.2 |
475 |
8.5 |
The high chromium and molybdenum content of super duplex Stainless steel makes it extremely resistant to uniform corrosion by organic acids like formic and acetic acid. It also provides excellent resistance to inorganic acids, especially those containing chlorides.
Specification
The Specification for Wrought super duplex round bar as per astm Standard is ASTM A276/ASME SA-276, they are categorised into different form and shape such as SS Super Duplex Round Bar, Rod, Channel Bar, T-Bar, Flat Bar, Blocks, Square, bar, Triangle, Threaded, Hex (A/F), Profiles, Half Ingot, Billet, I/H Bar, etc.
When considering wrought stainless round bars, material shall be furnished in the following way such as Hot-worked, Hot-worked and Annealed, Hot-worked- Annealed and cold worked or Hot-worked-Annealed and heat treated.
Round bars depending upon their treatment and their use and application they can also be available in different surface finishes such as Black, Bright Polished, Rough Turned, NO.4 Finish, Matt Finish, BA Finish, 2B, 2D. etc
Applications
- Desalination Equipment
- Chemical process pressure vessels, piping and heat exchangers
- Marine Applications
- Flue Gas Scrubbing Equipment
- Pulp & Paper Mill Equipment
- Offshore Oil production/technology
- Oil and gas industry equipment