Stainless Steel 418
Material Data Sheet
Stainless Steel 418, known as Greek Ascoloy, is a hardenable Chromium-Nickel-Tungsten martensitic stainless, intended for applications with service temperatures up to 1200°F.
418 Stainless has good resistance to scaling and oxidation at temperatures up to 1400°F. It resists atmospheric corrosion, weak organic acids, and oxidizing acids. It has the best corrosion resistance in the hardened and tempered condition.
Typically, Stainless 418 is used in such applications as steam turbine buckets and blades as well as compressor parts in gas turbines and high-temperature bolts.
Chemical Composition
| Element | Content (%) |
|---|---|
| Iron, Fe | 81.0 |
| Chromium, Cr | 13.0 |
| Tungsten, W | 3.0 |
| Nickel, Ni | 2.0 |
| Manganese, Mn | 0.25 |
| Silicon, S | 0.25 |
| Carbon, C | 0.18 |
| Phosphorus, P | 0.02 |
| Sulfur, S | 0.015 |
Physical Properties
| Property | Metric | Imperial |
|---|---|---|
| Density | 7.86 g/cc | 0.284 lb/in³ |
Mechanical Properties
| Property | Metric | Imperial |
|---|---|---|
| Hardness, Rockwell C | 25 | 25 |
| Tensile Strength | 895 MPa | 130000 psi |
| Yield Strength | 725 MPa | 105000 psi |
| Modulus of Elasticity | 190 – 210 GPa | 27557 – 30457 ksi |
| Poisson’s Ratio | 0.27 – 0.30 | 0.27 – 0.30 |
| Elongation at Break | 15% | 15% |
Applications
Stainless Steel 418 is used in the following application areas:
- Ducts
- Stiffeners
- Exhaust struts
- Engine braces
- Turbine exhaust components
