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35/45 Welding Wire Supplier - Nickel-Base 35Cr-45Ni-Nb Heat Resistant Filler | W.Nr. 1.4889
Nicorex Alloys is a Mumbai-based ISO 9001 and ISO 14001 certified supplier and stockist of 35/45 Nb welding wire. We supply high-performance 35/45 Nb filler metals in required classifications such as EN ISO 18274 and EN ISO 14343-A, and Mill test certificates.
35/45 Nb is a nickel-chromium filler with a nominal balance of Ni 45.6%, Cr 35%, and Fe 15.2%, stabilised with niobium (0.78%) and titanium (0.79%). This filler wire carries W.Nr. ~1.4889. Equivalent wire is known as Thermanit 35/45 Nb, UTP A 3545 Nb, and CEWELD 35-45 Nb. It operates in low-sulphur, carbon-enriching atmospheres up to 1175°C (2150°F), which is a full 125°C above, making it the reliable choice for the hottest zones in pyrolysis furnace coils and steam methane reformer tubes. The tensile strength is 690 MPa (100 ksi), the yield is 400 MPa (66.7 ksi), and the elongation is 15% in the as-welded condition. Nb/Ti precipitation enhances the strength of this material. Consequently, its carbon concentration is 0.04%.
We stock 35/45 Nb filler metal in MIG wire spools and TIG rods (2.4 mm and 3.2 mm diameters) to suit all industrial welding setups. MIG rods such as Thermanit 35/45 Nb can be obtained, whilst TIG rods are also available. Each Nicorex Alloys shipment includes EN 10204/3.1B mill test certificates, PMI reports, and traceability documentation.
35/45 Welding Wire Specifications
Refer to the following table for the standardised classifications and regulatory compliance data for 35/45 Nb filler metal products.
| Parameter | Details |
|---|---|
| Material Base | Nickel-Chromium (Ni 45.6%, Cr 35%) |
| AWS Classification | None assigned – order by EN ISO or trade name |
| Welding Process | GTAW (TIG), GMAW (MIG) – DC+ |
| Welding Positions | All positions (PA, PB, PC, PD, PE, PF) |
| TIG Rod Diameters | 2.4 mm, 3.2 mm × 1000 mm |
| Shielding Gas | I1 (100% Ar) per EN ISO 14175 |
| Packaging | 5 kg tubes (TIG rods) |
Understanding the 35/45 Nb Designation
Detailed 35/45 Nb alloy classification and technical compliance data are outlined in the following industrial reference table.
| Symbol | Meaning | Description |
|---|---|---|
| 35/45 | Nominal Alloy Content | Represents 35% Chromium and 45% Nickel. Since Nickel (45.6%) exceeds Chromium, it is classified as a Nickel-base alloy, not stainless steel. |
| Nb | Niobium Stabilization | Indicates the addition of Niobium to stabilise the alloy, which is critical for ASME Section IX procedure qualifications. |
35/45 Nb, an EN 18274-controlled nickel-base alloy, with high chromium and niobium concentration for high-temperature industrial performance and stability in hard environments. 35/45 Nb, a nickel-base alloy (ASME F-43) that meets ISO 18274, performs differently from stainless steel at high temperatures.
Weld Deposit Chemical Composition of 35/45 Nb
The typical all-weld-metal chemistry of 35/45 Nb is shown below. Nickel at 45.65% confirms the nickel-base designation and provides high-temperature stability.
| Element | Nickel (Ni) | Chromium (Cr) | Iron (Fe) | Silicon (Si) | Manganese (Mn) | Titanium (Ti) | Niobium (Nb) | Carbon (C) | Molybdenum (Mo) | Copper (Cu) | Aluminium (Al) |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Composition (wt%) | 45.65 (Balance) | 34.98 | 15.2 | 1.43 | 0.97 | 0.79 | 0.78 | 0.04 | 0.02 | 0.009 | 0.01 |
Chromium at 34.98% is the highest of any heat-resistant cast alloy filler, giving strong oxidation and carburisation resistance. Low carbon (0.04%) means this wire relies on Nb (0.78%) + Ti (0.79%) precipitation strengthening rather than carbide networks. High silicon (1.43%) increases resistance to carbon infiltration in cracking atmospheres. Iron is at 15.2%, significantly lower than the ~37% reported in 25/35.
All-Weld-Metal Mechanical Properties
Mechanical properties of 35/45 Nb all-weld metal in the as-welded condition are listed below. These values reflect the precipitation-strengthened nickel-base microstructure.
| Property | Tensile Strength (Rm) | Yield Strength (Rp0.2) | Elongation (A5) | Test Condition |
|---|---|---|---|---|
| Value | 690 MPa (100 ksi) | ≥400 MPa (58,000 psi) | 15% | As-welded |
A tensile strength of 690 MPa exceeds the 600 MPa typical of 25/35 weld deposits. The 15% elongation is standard for this class of high-performance heat-resistant filler, where creep resistance at 1175°C is the primary design factor.
Get 35/45 Welding Wire at Competitive Prices
Industrial Applications of 35/45 Welding Wire
The following are the industrial applications of 35/45 Welding Wire
- 35/45 Nb is essential for pyrolysis furnace coils operating in extreme heat. Its high chromium and niobium content prevents carburisation and coking while maintaining critical creep strength where standard alloys fail.
- 35/45 Nb is ideal for reformer outlet pigtails and high-temperature tube sections. Its superior thermal ceiling provides a critical safety margin during temperature spikes that would compromise standard alloys.
Available Forms of 35/45 Welding Wire
The following table details the available forms and packaging for 35/45 welding wire to suit various industrial fabrication requirements.
| Product Form | Diameter / Specifications | Packaging / Ordering Info |
|---|---|---|
| TIG Rods | 2.4 mm and 3.2 mm (1000 mm length) | 5 kg Tubes (In Stock) |
| MIG Wire Spools | Thermanit 35/45 Nb | Available on indent from voestalpine |
| Ordering Classifications |
Trade Names: Thermanit 35/45 Nb, UTP A 3545 Nb, CEWELD 35-45 Nb EN ISO: W Z 35 45 Nb |
|
How to Order 35/45 Welding Wire From Nicorex Alloys
To place an order or request a quotation from Nicorex Alloys, provide the following 10 details:
- Wire Type - GTAW / GMAW Solid Wire for Heat-Resistant Cast Alloys / Reformer & Pyrolysis Furnace Tube Welding (35/45 Nb)
- Size – Diameter: 1.6mm / 2.4mm / 3.2mm (GTAW cut lengths) / 1.2mm (GMAW spools) - specify form
- Current Type - DCEN (GTAW) / DCEP (GMAW) – specify process and diameter
- Welding Position - Flat & Horizontal preferred - specify if positional welding is required
- Material Grade - NiCr Heat-Resistant Alloy Wire / W.Nr. ~1.4889 / AWS Class 35/45 / ASME SFA A5.4 / DIN 12072
- Quantity -Number of spools/packs or total weight in kg
- Standard -AWS A5.4 / ASME SFA 5.4, DIN 12072, EN ISO 18274, ASME Section IX
- Documentation -MTC EN 10204 3.1/3.2, PMI Report, Weld Deposit Composition Report, Mechanical Properties Report, TPI Certificate
- Packaging -Vacuum-sealed foil bag with silica gel desiccant, ISPM 15 compliant export cartons with full labelling
- Delivery Destination -Domestic / International (specify port of discharge or delivery address)
Custom packaging and export-grade crating are available on request.
Frequently Asked Questions - 35/45 Welding Wire
Is 35/45 Nb a Stainless Steel or Nickel Alloy Filler?
35/45 Nb is a nickel-base alloy (Ni ~45.6%, Cr ~35%). Since nickel exceeds chromium, ASME and EN ISO standards classify it as nickel-based. F number 43 and EN ISO 18274, characteristics of nickel alloys, make it a nickel alloy filler
What is the Difference between 35/45 and 25/35 Welding Wire?
35/45 has higher Ni (45.6% vs 35.2%), higher Cr (35% vs 25.8%), lower carbon (0.04% vs 0.43%), and higher service temperature (1175°C vs 1050°C). 35/45 use Nb/Ti precipitation strengthening; 25/35 rely on carbon-based carbide networks. 35/45 is nickel-based (F-43); 25/35 is stainless (F-6).
Does 35/45 Have an AWS Classification?
No. 35/45 Nb is classified under EN ISO 14343-A (W Z 35 45 Nb) and EN ISO 18274 (S Ni Z NiCr36Fe15Nb0.8).
What Atmosphere Limitations Apply to 35/45 Welds?
35/45 Nb is rated for low-sulphur, carbon-enriching atmospheres up to 1175°C. It isn’t recommended for high-sulphur or vanadium-containing environments.
What is the Maximum Interpass Temperature for 35/45?
Maximum Interpass Temperature for 35/45 is 150°C. Low heat input is critical. No preheat or post-weld heat treatment (PWHT) is required.