Hangbo Alloy Group
Shanghai · Est. 2012
UNS N06052 / AWS A5.14 ERNiCrFe-7 / ISO 18274 SNi6062 — High-chromium nickel-iron welding wire engineered for Inconel 690, nuclear steam generator tube-to-tubesheet joints, and corrosion-resistant overlay cladding.
Inconel 52 — classified under AWS A5.14 as ERNiCrFe-7 and ISO 18274 as SNi6062 — is a high-chromium nickel-iron welding filler metal with UNS designation N06052. Developed to match the chemistry and corrosion resistance of Inconel 690 (UNS N06690), it has become the consumable of choice for critical nuclear steam generator tube-to-tubesheet welds, Inconel 690 overlay cladding, and dissimilar metal joints in high-temperature water service.
The defining feature of Inconel 52 is its elevated chromium content of 28.0-31.5%, roughly double that of the older ERNiCr-3 (Inconel 82) filler. This high chromium level produces a weld deposit with outstanding resistance to primary water stress-corrosion cracking (PWSCC), the life-limiting degradation mechanism in pressurized water reactor (PWR) steam generators. As the nuclear industry moved from Inconel 600 to Inconel 690 tubing, Inconel 52 and its modified variants (52M, 52MSS) became the standard filler metals for alloy 690 components.
For chemical processing, power generation, and offshore engineering, Inconel 52 also provides excellent oxidation resistance and good compatibility when joining nickel alloys to stainless or carbon steels. Hangbo Alloy Group supplies Inconel 52 as TIG rods, MIG wire, SAW wire, strip electrodes, and matching covered electrodes with full AWS/ASME certification.
Hangbo Alloy Group supplies nuclear-grade Inconel 52 TIG rods, MIG wire, SAW wire, strip electrodes, and ENiCrFe-7 covered electrodes — all with full material certification and traceability. Stock and mill orders available.
The chemical composition of Inconel 52 / ERNiCrFe-7 is controlled by AWS A5.14 to ensure a weld deposit that closely matches Inconel 690 base metal. The high chromium and nickel content provide the oxidation and stress-corrosion-cracking resistance required for nuclear and chemical service.
| Element | AWS A5.14 Range (wt%) | Typical Value | Role in the Weld Deposit |
|---|---|---|---|
| Nickel (Ni) | Remainder | ≥58 | Austenitic matrix, corrosion resistance, crack resistance |
| Chromium (Cr) | 28.0 – 31.5 | 29.5 | Cr₂O₃ protective scale; SCC and oxidation resistance |
| Iron (Fe) | 7.0 – 11.0 | 9.0 | Cost control, thermal expansion matching Inconel 690 |
| Niobium + Tantalum (Nb+Ta) | ≤ 1.0 | 0.5 | Carbide stabilization, improved creep strength |
| Titanium (Ti) | ≤ 1.0 | 0.3 | Deoxidation, grain refinement |
| Aluminum (Al) | ≤ 1.0 | 0.2 | Deoxidation, oxide-scale adhesion |
| Carbon (C) | ≤ 0.04 | 0.02 | Controlled low level to preserve corrosion resistance |
| Manganese (Mn) | ≤ 1.0 | 0.5 | Deoxidation, sulfur control |
| Silicon (Si) | ≤ 0.50 | 0.25 | Wetting and fluidity; controlled to limit cracking |
| Copper (Cu) | ≤ 0.50 | 0.1 | Trace impurity limit |
| Phosphorus (P) | ≤ 0.020 | 0.010 | Impurity control for ductility |
| Sulfur (S) | ≤ 0.015 | 0.008 | Impurity control for hot cracking resistance |
Key compositional insight: The chromium level in Inconel 52 is intentionally matched to Inconel 690 (29% Cr) rather than Inconel 600/601 (~15-16% Cr). This elevated chromium shifts the weld metal's corrosion potential into the "passive" regime in high-temperature pure water, dramatically improving resistance to primary water stress-corrosion cracking compared with ERNiCr-3 deposits.
Physical properties of the Inconel 52 deposit are similar to those of Inconel 690 base metal due to the closely matched chemistry.
| Property | Value | Notes |
|---|---|---|
| Density | ~8.19 g/cm³ | Similar to Inconel 690 |
| Melting Range | ~1340 – 1380 °C | Depends on exact composition |
| Thermal Expansion (20–1000°C) | ~15.5 × 10−6 /°C | Matches Inconel 690 |
| Thermal Conductivity (at 20°C) | ~12 W/(m·K) | Low; requires controlled heat input |
| Electrical Resistivity | ~1.15 μΩ·m | Typical nickel-alloy value |
| Magnetic Properties | Non-magnetic (austenitic FCC deposit) | |
| Crystal Structure | Face-Centered Cubic (FCC) | |
| Property | Typical Value | AWS A5.14 Minimum |
|---|---|---|
| Tensile Strength (Rm) | 550 – 700 MPa | ≥ 550 MPa |
| Yield Strength (Rp0.2) | 330 – 450 MPa | ≥ 330 MPa |
| Elongation (A) | 30 – 45% | ≥ 30% |
| Hardness | 180 – 230 HV | — |
Note: Actual mechanical properties depend on welding process, heat input, shielding gas, and dilution from base metal. Nuclear specifications often impose additional qualification testing beyond AWS minimums.
The Inconel 52 weld deposit retains good strength and oxidation resistance at elevated temperatures. It is suitable for service up to approximately 1150°C in oxidizing atmospheres, although its primary nuclear applications operate at 280–340°C. At these reactor temperatures, the key requirement is long-term stress-corrosion-cracking resistance rather than high-temperature strength.
| Parameter | GTAW | GMAW | SAW |
|---|---|---|---|
| Process polarity | DCEN | DCEP | DCEP |
| Shielding gas / flux | Ar or Ar-He | 98% Ar / 2% O₂ or Ni-alloy mix | Neutral/basic Ni-alloy flux |
| Typical heat input | 0.5 – 1.5 kJ/mm | 0.8 – 1.8 kJ/mm | 1.0 – 2.0 kJ/mm |
| Interpass temperature | ≤ 150 °C (300 °F) | ||
| Preheat | Generally not required for Ni alloys / austenitic SS; 50–100°C for thick carbon steel cladding | ||
Inconel 52 has good resistance to solidification cracking and liquation cracking due to its austenitic structure and controlled impurity levels. However, like many Ni-Cr-Fe alloys, it can be susceptible to ductility-dip cracking (DDC) at temperatures between approximately 700°C and 1100°C if heat input is excessive or restraint is high. Mitigation measures include:
Contact Hangbo Alloy Group for certified ERNiCrFe-7 TIG rods, MIG wire, SAW wire, strip electrodes, and ENiCrFe-7 covered electrodes. Competitive pricing, fast delivery, full mill test reports.
The high chromium content of the Inconel 52 deposit gives it excellent corrosion resistance in oxidizing environments and high-temperature aqueous media:
Hangbo Alloy Group supplies Inconel 52 / ERNiCrFe-7 in the following product forms, manufactured to AWS A5.14 / ASME SFA-5.14 specifications:
| Product Form | Applicable Standard | Typical Size Range |
|---|---|---|
| TIG Rods / Cut Lengths | AWS A5.14 ERNiCrFe-7 | Diameter 1.0 – 4.0 mm; lengths 914 / 1000 mm |
| MIG Wire (spools) | AWS A5.14 ERNiCrFe-7 | Diameter 0.8 – 1.6 mm; spools 5 – 15 kg |
| SAW Wire | AWS A5.14 ERNiCrFe-7 | Diameter 2.0 – 4.0 mm; coils / drums |
| Strip Electrodes | AWS A5.14 / proprietary | Thickness 0.4 – 0.8 mm; width 30 – 120 mm |
| Covered Electrodes | AWS A5.11 ENiCrFe-7 | Diameter 2.5 – 5.0 mm |
All products are supplied with EN 10204 Type 3.1 material certificates including chemical analysis, mechanical test results, and AWS/ASME conformance declarations. Nuclear-grade lots with full traceability and additional NDT are available on request.
| Standard | Description |
|---|---|
| AWS A5.14 / A5.14M | Specification for Nickel and Nickel-Alloy Bare Welding Electrodes and Rods — ERNiCrFe-7 |
| ASME SFA-5.14 / SFA-5.14M | ASME Boiler & Pressure Vessel Code equivalent |
| ASME IX | Qualification: F-No. 43 |
| UNS N06052 | Unified Numbering System designation |
| ISO 18274 | Welding consumables — solid wire and rods for fusion welding of nickel and nickel alloys — SNi6062 |
| AWS A5.11 / A5.11M | Specification for Nickel and Nickel-Alloy Covered Welding Electrodes — ENiCrFe-7 (Inconel 152) |
| NRC / 10 CFR 50 | Nuclear reactor construction and repair consumables |
| Property | Inconel 52 ERNiCrFe-7 | Inconel 82 ERNiCr-3 | Inconel 625 ERNiCrMo-3 |
|---|---|---|---|
| UNS | N06052 | N06082 | N06625 |
| Nominal Cr % | 28 – 31.5 | 13 – 17 | 20 – 23 |
| Mo % | — | — | 8 – 10 |
| Base metal match | Inconel 690 | Inconel 600/601 | Inconel 625 / 825 |
| PWR primary water SCC | Excellent | Good | Good |
| Oxidation resistance | Excellent | Good | Excellent |
| Reducing acid resistance | Fair | Fair | Excellent |
| Dissimilar metal welding | Good | Excellent | Good |
| Primary applications | Nuclear 690 welds, cladding | Ni-Cr-Fe general purpose | Corrosion-resistant Ni-Cr-Mo welds |
Selection guide: Choose Inconel 52 when welding or cladding Inconel 690 and when maximum resistance to primary water stress-corrosion cracking is required. Choose Inconel 82 for general Inconel 600/601, Incoloy 800, and dissimilar metal welds where lower cost is important. Choose Inconel 625 filler for aggressive reducing acids and marine environments.
Inconel 52 is a nickel-chromium-iron welding filler metal classified as AWS A5.14 ERNiCrFe-7, ISO 18274 SNi6062, and UNS N06052. It is designed to match Inconel 690 and is used for GTAW, GMAW, and SAW welding of Inconel 690 components, overlay cladding, and dissimilar metal welds. Its high chromium content gives superior resistance to stress-corrosion cracking in high-temperature pure water, making it the standard filler for nuclear steam generator tube-to-tubesheet joints.
Typical AWS A5.14 limits: Ni ≥58%, Cr 28.0-31.5%, Fe 7.0-11.0%, Nb+Ta ≤1.0%, Ti ≤1.0%, Al ≤1.0%, C ≤0.04%, Mn ≤1.0%, Si ≤0.50%, Cu ≤0.50%, P ≤0.020%, S ≤0.015%. The high chromium is the key feature, providing the oxidation and stress-corrosion-cracking resistance required for nuclear service.
Typical as-welded all-weld-metal properties: tensile strength ≥550 MPa, yield strength ≥330 MPa, elongation ≥30%, hardness 180-230 HV. The deposit is fully austenitic, non-magnetic, and highly ductile. Actual values depend on process, heat input, and dilution.
AWS A5.14 / A5.14M ERNiCrFe-7, ASME SFA-5.14 / SFA-5.14M, ASME IX F-No. 43, UNS N06052, ISO 18274 SNi6062, and the matching covered electrode AWS A5.11 ENiCrFe-7 (Inconel 152). It is qualified for nuclear pressure-boundary welding under ASME and NRC requirements.
Inconel 52 is used as solid wire for GTAW (TIG), GMAW (MIG), and SAW (submerged arc), and as strip electrode for electro-slag and submerged-arc strip cladding. Matching covered electrodes (ENiCrFe-7 / Inconel 152) are used for shielded metal arc welding. Shielding gases for GTAW/GMAW are typically argon or argon-helium mixtures.
Primary applications include nuclear steam generator tube-to-tubesheet welding, Inconel 690 tube repair and replacement, overlay cladding of reactor pressure vessel nozzles and heads, dissimilar metal welds between Inconel 690 and carbon/low-alloy steels, chemical process equipment, petrochemical furnace tubes, and power plant heat-exchanger components.
Inconel 52 has roughly twice the chromium of Inconel 82 (28-31.5% vs 13-17%), giving it better resistance to primary water stress-corrosion cracking and superior oxidation resistance. Inconel 82 is a more general-purpose filler for Inconel 600/601 and Incoloy 800 and is lower in cost. Inconel 52 is specifically matched to Inconel 690 for nuclear applications.
Inconel 52 is the original ERNiCrFe-7 composition. Inconel 52M (ERNiCrFe-7A) is a modified version with improved resistance to ductility-dip cracking. Inconel 52MSS is optimized for automated narrow-groove tube-to-tubesheet welding in nuclear steam generators, offering better arc stability and wetting. All three share the UNS N06052 base designation.
For GTAW, use DCEN polarity with argon shielding and heat input 0.5-1.5 kJ/mm. For GMAW, use pulsed-spray transfer with 98% Ar/2% O₂ or a nickel-alloy shielding gas and heat input 0.8-1.8 kJ/mm. Interpass temperature should be kept below 150°C. No preheat is required for nickel alloys or austenitic stainless steels.
Hangbo Alloy supplies Inconel 52 as TIG rods (1.0-4.0 mm), MIG wire on spools (0.8-1.6 mm), SAW wire (2.0-4.0 mm), strip electrodes for cladding (0.4-0.8 mm thick, 30-120 mm wide), and covered electrodes ENiCrFe-7 / Inconel 152 (2.5-5.0 mm). All forms can be supplied with AWS/ASME certification and full traceability.
Inconel 52 is a premium nuclear-grade filler. Typical pricing is $55-120/kg depending on product form, diameter, certification level, and current raw-material markets. Nuclear-grade lots with EN 10204 3.1/3.2 certificates are at the upper end. Lead times range from 4-8 weeks for standard sizes and 8-14 weeks for certified nuclear lots. Contact serena@hangboalloy.com for a competitive quote.
Yes. The high chromium content (~29%) gives Inconel 52 excellent oxidation resistance and outstanding resistance to primary water stress-corrosion cracking in nuclear steam generators. It also resists caustic and nitric acid environments. For strongly reducing hydrochloric or sulfuric acids, Hastelloy-type fillers are preferred.
Yes. Inconel 52 is commonly used for dissimilar metal welds between Inconel 690 or Inconel 600 and carbon steel, low-alloy steel, or austenitic stainless steel. The nickel-rich austenitic deposit accommodates thermal expansion mismatch and provides a corrosion-resistant transition. Applications include nuclear safe-end welds, petrochemical transition joints, and power plant repairs.
