254SMo Stainless Steel
254SMo is a super austenitic stainless steel containing 19.5% to 20.5% chromium, 17.5% to 18.5% nickel, 6.0% to 6.5% molybdenum, and smaller amounts of nitrogen and copper. The molybdenum and nitrogen content supports resistance to pitting, crevice corrosion, and stress corrosion in chlorides, sulfuric acid, hydrochloric acid, and seawater. Carbon is limited to ≤0.02%. The source also describes higher mechanical strength than conventional austenitic stainless steel, together with toughness, weldability, and stable high temperature performance for severe corrosive service.
Product details
Chemical composition
| 254SMo | C | Si | Mn | P | S | Ni | Cr | Cu | Mo | N |
|---|---|---|---|---|---|---|---|---|---|---|
| min | – | – | – | – | – | 17.5 | 19.5 | 0.5 | 6.0 | 0.18 |
| max | 0.02 | 0.8 | 1.0 | 0.03 | 0.01 | 18.5 | 20.5 | 1.0 | 6.5 | 0.22 |
Grade equivalents
| English Item | UNS | W.Nr. | JIS | GB/T | Other Grades |
|---|---|---|---|---|---|
| 254SMo | S31254 | 1.4547 | – | F44 015Cr20Ni18Mo6CuN 00Cr20Ni18Mo6CuN | X1CrNiMoCuN20-18-7 |
Physical properties
| Density g/cm³ | 8.24 |
|---|---|
| Melting range ℃ | 1320-1390 |
| Thermal conductivity (100℃) λ/(W/m•℃) | 14.5 |
| Specific heat J/kg•℃ | 500 |
| Elastic modulus GPa | 195 |
| Electrical resistivity μΩ•m | 0.85 |
| Linear expansion coefficient a/10-6℃-1 | 16.5 |
Mechanical properties
| Tensile strength Rm N/mm | ≥650 |
|---|---|
| Yield strength RP0.2 N/mm | ≥310 |
| Elongation % | ≥35 |
| Hardness HB | 182-223 |
| *After solution heat treatment | |
Available product forms
- Round Bar
- Plate
- Pipe & Tube
- Welding Consumables
- Flanges
- Hex Bolts
- Threaded Rod
- Nuts & Washers
Technical values are transcribed and translated from the supplied Milike Chinese catalogue. Confirm the applicable purchase specification, heat treatment condition, and inspection requirements before final material selection.
Need a different size, condition, or inspection route?
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