Type 2507 (UNS S32750)
Description
2507 stainless steel was designed for demanding applications which require exceptional strength and corrosion resistance, such as chemical process, petrochemical, and seawater equipment. As a duplex (ferritic-austenitic) stainless steel, 2507 combines the most desirable characteristics of both ferritic and austenitic steels.
The duplex microstructure gives this grade high strength, excellent resistance to chloride stress corrosion cracking, high thermal conductivity, and a low coefficient of thermal expansion. In addition, 2507’s high chromium, molybdenum, and nitrogen levels provide excellent resistance to pitting, crevice, and general corrosion that is similar to the 6% Mo super austenitic stainless steels.
Chemical Composition
Chemical Composition (wt%) limits as specified in ASTM A276 and ASME SA276*
| Carbon | 0.030 | Silicon | 0.80 |
| Chromium | 24.0-26.0 | Copper | 0.50 |
| Nickel | 6.0-8.0 | Nitrogen | 0.24-0.32 |
| Molybdenum | 3.0-5.0 | Phosphorus | 0.035 |
| Manganese | 1.20 | Sulfur | 0.020 |
*Maximum, unless range is indicated
Physical Properties
Physical properties for Super Duplex 2507 Stainless Steel
| Density, lb/in3 | 0.280 |
| Modulus of Elasticity, psi | 29.0x 106 |
| Coefficient of Thermal Expansion, 68-212˚F, /˚F | 7.5 x 10-6 |
| Thermal Conductivity, Btu/ft hr ˚F | 8 |
| Specific Heat, Btu/lb ˚F | 0.12 |
| Electrical Resistivity, Microhm-in | 31.5 |
Mechanical Properties
Mechanical property requirements for annealed, hot finished product as specified in ASTM A276 and ASME SA276
| Yield Strength, min. (ksi) | 80 |
| Tensile Strength, min. (ksi) | 116 |
| Elongation, min. (%) | 15 |
| Hardness, max. (HBW) | 310 |
Standards
Typical standards for Super Duplex 2507 Stainless Steel
| ASTM A276 |
| ASTM A479 |
| ASME SA276 |
| ASME SA479 |