Is Incoloy 825 alloy better than Incoloy 800 alloy?
Is Incoloy 825 alloy better than Incoloy 800 alloy?
Neither alloy is inherently superior; the choice depends on the specific application. Due to the addition of molybdenum and copper, Incoloy 825 offers better corrosion resistance, especially in acidic and chlorine-rich environments. Incoloy 800, on the other hand, is commonly used in applications requiring higher high-temperature strength and oxidation resistance at a lower cost.
What are the uses of INCOLOY 800?
It is used in heat treatment equipment such as baskets, pallets, and clamps. In chemical and petrochemical processing, this alloy is used in heat exchangers and other piping systems for nitric acid media, particularly suitable for applications requiring resistance to chloride stress corrosion cracking.
Incoloy 800 and 825 are two widely used nickel-iron-chromium alloys, renowned for their excellent corrosion resistance, mechanical strength, and suitability for high-temperature environments. While these two alloys share many common properties, they also have significant differences that make them more suitable for specific applications. This article will explore the properties, differences, and uses of Incoloy 800 and 825.
What is Incoloy Alloy 825 (UNS N08825 / W.Nr. 2.4858)?
Incoloy 825 is a nickel-iron-chromium alloy with added molybdenum (Mo), copper (Cu), and titanium (Ti) elements, enhancing its corrosion resistance in reducing acids, seawater, and chloride environments.
Its core advantages include:
In sulfuric acid, phosphoric acid, and chloride environments, its resistance to pitting corrosion, crevice corrosion, and stress corrosion cracking is significantly superior to Incoloy 800.
Furthermore, it possesses higher mechanical strength: typical tensile strength ≥ 550 MPa, yield strength ≥ 220 MPa.
It is commonly used in harsh environments such as chemical plants, offshore platforms, and pollution treatment facilities.
As an export manufacturer, Gnee Steel offers customized Incoloy 825 alloys and provides relevant technical data. Please contact customer service immediately for the latest quotes and delivery times for Incoloy 825 alloys.
What is Incoloy Alloy 800 (UNS N08800 / W.Nr. 1.4876)?
Incoloy 800 is a nickel-iron-chromium alloy with a typical chemical composition of 30-35% nickel, 19-23% chromium, and the remainder iron. It is specifically designed to maintain strength and stability in high-temperature oxidizing, carburizing, and nitriding environments.
Its key features include:
Excellent resistance to oxidation, nitriding, and carburizing makes it ideal for tube bundles and components in heat exchangers, industrial furnaces, and petrochemical cracking units.
It maintains good strength at temperatures exceeding 1000°C.
Its excellent weldability and machinability make it suitable for manufacturing a wide variety of structural components.
Gnee Steel supplies directly, with ample stock and support for global exports. Request a quote for Incoloy 800 alloy today, including minimum order quantities and stock availability.
Incoloy 800 vs 825 Alloy – What's the Difference?
Chemical Composition: Incoloy 800 vs 825 Alloy
| Element | Incoloy 800 | Incoloy 825 |
|---|---|---|
| Ni | 30–35% | 38–46% |
| Cr | 19–23% | 19.5–23.5% |
| Fe | Balance | Balance |
| Mo | – | 2.5–3.5% |
| Cu | – | 1.5–3% |
| Ti | ≤ 0.6% | 0.6–1.2% |
| C | ≤ 0.10% | ≤ 0.05% |
| Si | ≤ 1.0% | ≤ 0.5% |
| Mn | ≤ 1.5% | ≤ 1.0% |
Mechanical properties: Incoloy 800 and 825 alloys
| Property | Incoloy 800 | Incoloy 825 |
|---|---|---|
| Tensile Strength | ≥ 450 MPa | ≥ 550 MPa |
| Yield Strength | ≥ 170 MPa | ≥ 220 MPa |
| Elongation | ≥ 30% | ≥ 30% |
| Hardness (Rockwell) | B85–B90 | B88–B93 |
Physical Properties: Incoloy 800 vs 825 Alloy
| Property | Incoloy 800 | Incoloy 825 |
|---|---|---|
| Density | 7.94 g/cm³ | 7.94 g/cm³ |
| Melting Range | 1357–1385°C | 1370–1400°C |
| Thermal Conductivity | 11.2 W/m·K (at 100°C) | 11.1 W/m·K (at 100°C) |
| Specific Heat Capacity | ~502 J/kg·K | ~460 J/kg·K |
| Electrical Resistivity | 0.98 μΩ·m | 1.03 μΩ·m |
Application Industries and Case Studies
1. Applications of Incoloy 800 Alloy
Petrochemical heaters and reformers.
Industrial furnaces, burners, and heat exchangers.
Power generation steam superheaters.
Boiler components and pressure vessels.
2. Applications of Incoloy 825 Alloy
Sulfuric acid and phosphoric acid production units.
Seawater desalination and cooling systems.
Marine pollution control and offshore oil platforms.
Chemical storage tanks, heat exchangers, and scrubbers.
Which is Better? Incoloy 800 vs 825 Alloy
| Project Environment | Recommended Alloy | Reason |
|---|---|---|
| High-temperature oxidizing furnaces | Incoloy 800 | Superior oxidation resistance |
| Sulfuric acid or phosphoric acid processing | Incoloy 825 | Strong acid corrosion resistance |
| Marine / Seawater systems | Incoloy 825 | Excellent chloride resistance |
| Heat exchangers / pressure vessels | Incoloy 800 | Cost-effective under heat stress |
| Pollution control / waste treatment | Incoloy 825 | Resists acid gases and condensates |
Why Choose Gnee Nickel Alloy (Supplier Example)?
✅ Large stock of Incoloy alloy tubes/bars/plates/fittings/coils, fast shipping.
✅ Factory direct sales, highly competitive prices, excellent value for money.
✅ Comprehensive quality assurance: Material Testing Certificate (MTC), chemical composition certificate, and mechanical property certificate.
✅ Value-added services: slitting, cutting, polishing, surface treatment.
✅ Worldwide shipping, secure and reliable packaging, and provision of export-required documents.
Email: ss@gneemetal.com
Gnee Steel is a supplier of Incoloy 800/825 alloy, offering a wide range of products including: seamless pipe (sizes: 4-219 mm; thickness: 0.5-20 mm); welded pipe (sizes: 5.0-1219.2 mm; thickness: 0.5-20 mm); plates (thickness: 0.1 to 100 mm; width: 10-2500 mm); strips; alloy round bars (diameter: 3-800 mm); flat bars (thickness: 2-100 mm; width: 10-500 mm); hexagonal bars (size: 2-100 mm); wire rods; and extruded profiles. We collaborate with steel mills to provide our customers with Incoloy 800/825 alloy products that meet or exceed numerous leading industry standards, including ASTM, ASME, SAE, AMS, ISO, DIN, EN, and BS standards.
Gnee Steel stocks and sells Incoloy 800/825, pipes, plates, strips, round bars, flat bars, forged billets, hexagonal steel, wire rods, and extruded profiles. Please feel free to contact us at ss@gneesteel.com for a quote.
