ERNiMo-7 – wire and rod for Hastelloy B-2
Nickel-molybdenum filler metal (28 % Mo) for alloy B-2, used with hydrochloric acid and other strongly reducing media.
Product forms and equivalents
| Process | Classification |
|---|---|
| TIG rod (GTAW) | ERNiMo-7 |
| Solid MIG/MAG wire (GMAW) | ERNiMo-7 |
| Covered electrode (SMAW) | ENiMo-7 – AWS A5.11 |
| Designation | Value |
|---|---|
| AWS | ERNiMo-7 |
| Specification | AWS A5.14/A5.14M / ASME SFA-5.14 |
| UNS | N10665 |
| Others | EN ISO 18274: S Ni 1066 (NiMo28); W.Nr. 2.4615 |
| Trade designation | Liga B-2 / Hastelloy B-2 (designação de material) |
Chemical composition (%)
| Element | wt. % |
|---|---|
| C | ≤ 0.02 |
| Mo | 26.0 – 30.0 |
| Fe | ≤ 2.0 |
| Cr | ≤ 1.0 |
| Co | ≤ 1.0 |
| W | ≤ 1.0 |
| Ni | Balance |
| Mn | ≤ 1.0 |
| Si | ≤ 0.10 |
| Cu | ≤ 0.50 |
| P | ≤ 0.04 |
| S | ≤ 0.03 |
Properties of the deposited metal
| Property | Value |
|---|---|
| Tensile strength of deposited metal | ≥ 760 MPa (AWS A5.11 minimum for ENiMo-7, reference) |
| Elongation | ≥ 25 % (AWS A5.11 minimum for ENiMo-7, reference) |
Materials welded with ERNiMo-7
Why the composition differs from the base metal
The chemistry follows that of alloy B-2, with very low carbon and silicon and limited iron and chromium. Those limits prevent carbides and brittle Ni-Mo phases in the fusion zone, which would cause preferential corrosion of the bead in hydrochloric acid.
Welding precautions
- No preheating; interpass below 100 °C.
- Low heat input; the bead does not tolerate oxidizing media or iron contamination well.
- TIG with pure argon or argon-helium; argon root purge. Rigorous cleaning: oil, paint and markers contaminate the nickel alloy with sulfur and lead.
Frequently asked questions
What is ERNiMo-7 used for?
Nickel-molybdenum filler metal (28 % Mo) for alloy B-2, used with hydrochloric acid and other strongly reducing media.
Why is the composition of ERNiMo-7 different from the material it welds?
The chemistry follows that of alloy B-2, with very low carbon and silicon and limited iron and chromium. Those limits prevent carbides and brittle Ni-Mo phases in the fusion zone, which would cause preferential corrosion of the bead in hydrochloric acid.
Which covered electrode corresponds to ERNiMo-7?
ENiMo-7 – AWS A5.11.
What precautions apply when welding with ERNiMo-7?
No preheating; interpass below 100 °C. Low heat input; the bead does not tolerate oxidizing media or iron contamination well. TIG with pure argon or argon-helium; argon root purge. Rigorous cleaning: oil, paint and markers contaminate the nickel alloy with sulfur and lead.
