Chemical components

Product Description

ERNiCr-4 is a premium nickel-chromium alloy solid welding wire compliant with AWS A5.14/A5.14M standards, designed for overlaying carbon and stainless steels to provide a nickel-chromium alloy corrosion-resistant surface in high-temperature sulfur and vanadium atmospheres. Featuring a high-nickel composition (≥55wt.%) and high chromium content (42.0-46.0wt.%) for enhanced oxidation resistance, with titanium (0.3-1.0wt.%) for stabilization and superior performance in high-temperature fuel-ash corrosive environments. Compatible with GTAW (TIG), GMAW (MIG), and SAW processes, it provides exceptional resistance to high-temperature corrosion, fuel-ash corrosion, and erosion in sulfur-containing atmospheres.

Features

▪ Superior High-Temperature Corrosion Resistance: The high chromium content (42-46%) forms a dense Cr₂O₃ oxide layer that effectively blocks sulfur and vanadium penetration, resulting in an annual corrosion rate of less than 0.5mm at 870°C in sulfur-containing flue gas, representing an 80% reduction compared to conventional stainless steel welding materials.
▪ Excellent Oxidation Resistance: The balanced nickel-chromium alloy system provides outstanding oxidation resistance at elevated temperatures. The weld metal maintains excellent stability and integrity during thermal cycling, with the chromium oxide layer exhibiting self-healing properties to ensure long-term protection against oxidation and corrosion.
▪ Stable Weld Metal: Titanium stabilization inhibits carbide precipitation and prevents intergranular embrittlement, ensuring high ductility and mechanical integrity in the as-welded condition. The controlled chemical composition with low carbon, manganese, silicon, iron, and strict control of sulfur and phosphorus minimizes high-temperature brittleness.
▪ Excellent Weldability: Provides smooth arc stability, minimal spatter, and uniform bead formation across various welding positions. Compatible with DCEN (GTAW) and DCEP (GMAW) modes with recommended interpass temperatures up to 150°C. For high constraint thick plates, preheating to 150-200°C is recommended to control residual stresses.

Applications

▪ Ideal for high-temperature corrosive environments, ERNiCr-4 is widely used in:
▪ Power Generation: Coal-fired power plant boiler water wall overlay, especially in low NOx burner zones exposed to 850°C flue gas containing Cl⁻ and SO₂. Provides maintenance-free service life of up to 4 years, extending maintenance cycles by three times compared to traditional materials.
Chemical Processing: Heavy oil cracking furnace Cr5Mo furnace tube surfacing, providing excellent corrosion resistance with annual corrosion rates of less than 0.05mm in 50% NaOH/140°C environments. Also suitable for chemical reactors, distillation columns, and piping systems handling aggressive media.
▪ Waste Incineration: Municipal solid waste and hazardous waste incineration plants, where components are exposed to high-temperature corrosive flue gases containing sulfur, chlorine, and heavy metal compounds. The weld metal's exceptional resistance to fuel-ash corrosion extends equipment service life.
▪ Metal Casting & Foundry: Used for welding and overlaying Ni-Cr and Ni-Fe-CR components, including nickel-iron-chromium tubes and castings exposed to high-temperature corrosive atmospheres. Provides reliable performance in furnace components, molds, and heat treatment equipment.