The S32750 (F53 / SAF2507) alloy is a super duplex stainless steel consisting of 25% Cr, 4% Mo and 7% Ni and added N elements to the component. The steel is mainly used for special strength and corrosion resistance requirements of chemical, petrochemical and marine equipment.
S32750 has a strong resistance to chloride stress corrosion cracking, high thermal conductivity and low coefficient of thermal expansion. High chromium, molybdenum, nickel content and added nitrogen make it a high resistance to pitting, crevice corrosion and general corrosion. The higher nitrogen content also increases its crystal structure stability.
S32750 compared to dual-phase steel 2205, with more suitable for extreme corrosion environment corrosion resistance. Its impact strength is also high, but the S32750 alloy is not suitable for use in the temperature above 570 ° F (299 ° C) environment, because long-term in such an environment, its toughness will be reduced.
| UNS Designation | C | Si | Mn | P | S | Cr | Ni | Mo | N | Cu |
| max | max | max | max | max |
| S31803 | 0.03 | 1 | 2 | 0.03 | 0.02 | 21.0 - 23.0 | 4.5 - 6.5 | 2.5 - 3.5 | 0.08 - 0.20 | - |
| S32205 | 0.03 | 1 | 2 | 0.03 | 0.02 | 22.0 - 23.0 | 4.5 - 6.5 | 3.0 - 3.5 | 0.14 - 0.20 | - |
| S32750 | 0.03 | 0.8 | 1.2 | 0.035 | 0.02 | 24.0 - 26.0 | 6.0 - 8.0 | 3.0 - 5.0 | 0.24 - 0.32 | 0.5 max |
| S32760 | 0.05 | 1 | 1 | 0.03 | 0.01 | 24.0 - 26.0 | 6.0 - 8.0 | 3.0 - 4.0 | 0.20 - 0.30 | 0.50 -1.00 |
