- Grade / Alloy
- Alloy 617
- EN / W.Nr.
- 2.4663
- AISI / SAE
- —
- UNS
- N06617
- Family
- Solid-solution alloy
Chemical composition
Chemical composition
Typical compositionTypical composition of the principal alloying elements; not a complete acceptance analysis.
| Element | Content (% by mass) |
|---|---|
| NiNickel | 55 |
| CrChromium | 22 |
| FeIron | 1 |
| MoMolybdenum | 9 |
| CoCobalt | 11.5 |
| AlAluminium | 1.1 |
Values describe the grade, not the analysis of a specific batch. The applicable product specification and material certificate determine acceptance. A dash does not mean zero.
The main characteristic of 617
617 serves duties requiring both surface resistance and retained mechanical properties while hot. Chromium and aluminium contribute to oxidation resistance; cobalt and molybdenum support hot strength. This combination suits hot sections of energy and aerospace equipment.
Behaviour under sustained loading
A hot metal can gradually deform under a constant load, a behaviour called creep. This matters in continuously heated equipment. Alloy 617 is therefore valued for sustained-temperature performance as well as short-duration tensile strength.
Hot-gas and heat-transfer equipment
Combustion components, turbine transition ducts and high-temperature exchangers are typical examples. The alloy also serves process equipment combining hot gases with heat transfer, where gas resistance and mechanical load capacity complement each other.
Distinguishing 617 from 625
617 and 625 are different compositions despite similar numbers. Cobalt and high-temperature duties are prominent for 617; niobium and molybdenum characterise 625 and its broad corrosion applications. The numbers do not indicate successive versions.
Typical application areas
Turbine combustion components, hot-gas ducts and high-temperature heat exchangers.
Product and cutting options
Relevant product forms for this material are listed below. Availability varies with grade and dimensions.