Nickel-base electrodes for dissimilar joints and cryogenic service
ENiCrFe-2 weld metal is nickel-based with chromium and iron additions. Its service temperature range runs from cryogenic up to 1500°F (about 815°C), combining two properties: buffering in dissimilar metal welds and toughness at low temperatures. This page offers AWS A5.11 ENiCrFe-2 (also called Alloy A), Ø4.0 mm, for similar and dissimilar welding of carbon steel, austenitic and ferritic stainless steels, alloy 600, alloy 800 and 5% / 9% nickel cryogenic steels — used in cryogenic tanks, chemical equipment, power plants and dissimilar metal joints.
This series is for corrosion-resistant nickel-base welding, a higher specification than general-purpose electrodes and low-alloy structural steel electrodes. A JIAHON affiliated company supplies customers throughout Taiwan; AWS A5.11 nickel alloy electrodes can be supplied with full MTC material certificates and documentation for PED / ASME on request.
Specifications
| Item | Details |
|---|---|
| Classification / name | ENiCrFe-2 (Alloy A) |
| Diameter | 4.0 mm |
| Standards | AWS A5.11 ENiCrFe-2 (UNS W86133) / JIS Z3224 ENi6133 / EN ISO 14172 E Ni 6092 / GB/T 13814 ENiCrFe-2 |
| Process | SMAW (shielded metal arc welding, covered electrodes) |
| Main composition | Ni-Cr-Fe; C ≤ 0.10%, Cu ≤ 0.50% (per AWS A5.11 chemical requirements) |
| Base metals | Wrought and cast carbon steel, austenitic and ferritic stainless steels, alloy 600, alloy 800, 5% / 9% nickel cryogenic steels; also nickel-base alloys to each other and dissimilar metals |
| Service temperature | Cryogenic to 1500°F (about 815°C) |
| Typical uses | LNG tanks, liquid nitrogen tanks, welding 9% nickel cryogenic steel; dissimilar joints; overlay with matching alloy |
| Packing | 2.5 kg / box, 5 kg / box |
| Before use | Re-drying and holding conditions per the electrode manufacturer’s datasheet; take out only the day’s requirement |
Values are common industry ranges for ENiCrFe-2; actual chemistry and mechanical properties are per the supplier’s MTC and datasheet. For formal purchases, confirm against your welding procedure specification (WPS) and owner’s specification, case by case.
Applications
- Cryogenic tanks and nickel cryogenic steels: LNG tanks, liquid nitrogen tanks and 5% / 9% nickel steel cryogenic vessels; ENiCrFe-2 keeps good toughness at cryogenic temperatures and is one of the standard electrodes for these steels.
- Dissimilar joints between carbon steel and stainless steel: carbon steel to stainless steel, and stainless steel to alloy 600 / alloy 800; ENiCrFe-2 buffers the composition difference, avoiding corrosion in the dilution zone and thermal stress cracking.
- Similar welding of alloy 600 / alloy 800: welding and repair of nickel-chromium-iron alloy structures.
- Overlay in chemical equipment and power plants: surfacing with matching nickel-chromium alloy for oxidation and corrosion resistance.
Nickel alloy vs low-alloy steel electrodes
| Item | Low-alloy steel electrodes (B series) | Nickel alloy electrodes (A5.11) |
|---|---|---|
| Base composition | Iron base + 1–9% Cr + 0.5–1% Mo | Nickel base 50–70% + high Cr / Mo / Nb |
| Max. service temperature | 540–600°C | 700–1100°C (some classes such as ENiCrFe-2 cover cryogenic to 815°C) |
| Resistance to strong corrosion | Ordinary (not resistant to strong acids and alkalis at high temperature) | Very good (HCl / H₂SO₄ / seawater / H₂S) |
| Stress corrosion cracking resistance | Medium | Good |
| Main uses | Power plants, structural steel, pressure vessels | Strong acids in chemical plants, marine, gas turbines, pharmaceuticals, cryogenic tanks |
| Welding difficulty | Needs preheat + PWHT | High hot-cracking risk; needs low heat input |
How to decide: look at the corrosive medium. No strong corrosion, only high temperature and pressure → low-alloy steel electrodes are enough; strong acids or alkalis, marine, H₂S or clean pharmaceutical service → upgrade to nickel alloy. Misuse wastes money (nickel alloy where low-alloy is enough) or causes failure (low-alloy in strong corrosion).
AWS A5.11 classifications
| Classification | Composition | Base metal | Main applications |
|---|---|---|---|
| ENiCrFe-2 (Alloy A) | Ni-Cr-Fe | Carbon steel, stainless steel, alloy 600, alloy 800, 5% / 9% nickel steels | Cryogenic tanks (LNG), dissimilar joints |
| ENiCrFe-3 | 72Ni-15Cr-9Fe + Nb | Alloy 600 | High-temperature oxidation, gas turbines |
| ENiCrFe-7 | 60Ni-30Cr-9Fe + Nb | Alloy 690 | Nuclear steam generators |
| ENiCrMo-3 | 61Ni-22Cr-9Mo-3.5Nb | Alloy 625 | Offshore oil and gas, seawater heat exchangers |
| ENiCrMo-4 | 57Ni-16Cr-16Mo-4W | C-276 | Strong acids in chemical plants (HCl / H₂SO₄) |
| ENiCrMo-10 | 59Ni-22Cr-13Mo | C-22 | Both strongly oxidizing and strongly reducing environments |
| ENi-1 | Pure nickel ≥ 95% | Nickel 200 / 201 | Strong alkali (NaOH), food and pharmaceuticals |
| ENiCu-7 | 67Ni-30Cu | Alloy 400 | Seawater, hydrofluoric acid |
This page supplies ENiCrFe-2 (Alloy A) Ø4.0 mm; other classifications on request.
Naming: E (electrode) + Ni (nickel base) + Cr (chromium) + Fe / Mo (iron or molybdenum) + number (composition code). ENiCrFe classes rely on Cr + Fe for high-temperature oxidation protection, and ENiCrFe-2 (Alloy A) covers service from cryogenic to about 815°C, commonly used for 5% / 9% nickel steels and dissimilar joints. ENiCrMo classes rely on Cr + Mo for strong acid resistance; ENi pure nickel classes are for strong alkalis or food and pharmaceutical service.
Hot cracking: why nickel alloys are hard to weld
Impurities such as sulfur and phosphorus have very low solubility in nickel-base weld pools (sulfur solubility in pure nickel < 0.01%). During solidification they are pushed to the grain boundaries and form a low-melting Ni-S eutectic (melting point 645°C); as the weld cools, the boundaries are still liquid while the surroundings have solidified, causing hot cracks that may only be found by X-ray inspection.
| Precaution | Method | Effect |
|---|---|---|
| 1. Electrode impurity control | electrodes classified to AWS A5.11, with MTC | Controls S / P at the source |
| 2. Low heat input | Smaller 2.6 / 3.2 mm electrodes (this page is 4.0 mm; other sizes on request), low current, faster travel | Shortens time the pool stays hot |
| 3. No weaving | Straight stringer beads, avoid wide weaving | Keeps the pool narrow |
| 4. Narrow beads | Bead width < 3 × electrode diameter | Smaller pool volume |
| 5. Clean between passes | Remove slag thoroughly before each pass | Avoids slag inclusions |
| 6. TIG for high-Mo classes | Use ERNiCrMo-4 TIG instead of ENiCrMo-4 (C-276) | Finer heat input control |
| 7. Clean the joint | Wipe with acetone / isopropanol to remove oil and oxide | Avoids pool contamination |
Selection and purchasing
- Selection: service environment (medium, temperature, pressure) → base metal → AWS A5.11 class (matching the base metal) → process (SMAW / TIG) → code verification (NACE / ASME).
- NACE MR0175 / ISO 15156: the international standard for metallic materials in sour (H₂S) service, with requirements on weld hardness and non-sensitized microstructure. Confirm specific hardness values, procedure qualification (WPS + PQR + WPQ) and NDE extent against the standard and owner’s specification. For deep-sea oil and gas, FPSO platforms and sour gas well piping, require NACE compliance documentation from the supplier.
- For formal purchases, ask for: MTC with full chemistry (Ni / Cr / Mo / Fe / Nb / S / P), mechanical properties (tensile strength, yield, Charpy V impact), corrosion tests (ASTM G28, G48, etc.), NACE compliance, supplier PED / ASME qualification and batch traceability.
When you request a quote, please tell us: classification, diameter, quantity (kg), base metals and service conditions.
Email us for a quote: [email protected]