- Grade / Alloy
- Alloy B-2
- EN / W.Nr.
- 2.4617
- AISI / SAE
- —
- UNS
- N10665
- 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 | 69 |
| CrChromium | 0.7 |
| FeIron | 1.8 |
| MoMolybdenum | 27 |
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 composition that makes B-2 different
B-2 has a high molybdenum content and much less chromium than many C-family alloys. Its corrosion resistance is therefore associated particularly with non-oxidising, or reducing, acids rather than uniform protection in every chemical.
Hydrochloric acid applications
Hydrochloric acid is demanding for many conventional metals. B-2 is a specialised option for reactors, pipes and exchangers handling it. Certain sulphuric-acid conditions and organic acids are other applications, with wetted-surface resistance the main benefit.
The distinction for oxidising chemicals
Ferric ions and other oxidising constituents can change an acid solution’s behaviour. B-2’s low chromium content makes this distinction important. Its strength in reducing acids must not be extended into a blanket claim for oxidising chemicals.
B-2 and other Hastelloy names
B-2 does not stand for the whole Hastelloy family. B-3, C-22 and C-276 are separate compositions. The identifiers for B-2 are 2.4617 and N10665, preserving the distinction between these materials.
Typical application areas
Hydrochloric acid equipment, reactors, heat exchangers and acid lines.
Product and cutting options
Relevant product forms for this material are listed below. Availability varies with grade and dimensions.