Incoloy 800 Product Introduction
Product Overview
Incoloy 800 is a nickel-iron-chromium-based high-temperature corrosion-resistant alloy developed by Special Metals Corporation (USA), primarily designed for elevated-temperature applications requiring oxidation and carburization resistance. Its optimized composition (high chromium for high-temperature oxidation protection, nickel for matrix stability, and titanium for grain boundary strengthening) enables it to maintain excellent mechanical properties and structural stability at temperatures up to 870°C. Unlike Incoloy 825 (focused on acidic corrosion), Incoloy 800 excels in resisting oxidation, nitridation, and carburization in high-temperature atmospheres (e.g., industrial furnace flue gas, steam). Widely used in petrochemical, power generation, and metallurgical industries, it is a reliable material for high-temperature components where conventional alloys fail to withstand long-term thermal stress and corrosion.
International Grade Comparison
Standard System | Grade | Description |
ASTM (USA) | N08800 | UNS Unified Numbering System Grade |
EN (EU) | NiCr20Fe | EN 10088-1 Standard Grade |
JIS (Japan) | NW08800 | JIS G4902 Standard Grade |
DIN (Germany) | 1.4876 | DIN 17750 Standard Grade |
ISO (International) | NiCr20Fe | ISO 6363 Standard Grade |
Physical Properties (Room Temperature, Key Brief Indicators)
Property Indicator | Typical Value | Unit |
Tensile Strength | ≥505 | MPa |
Yield Strength (0.2% Offset) | ≥215 | MPa |
Elongation (50mm Gauge Length) | ≥35 | % |
Density | 8.0 | g/cm³ |
Melting Point | 1400-1450 | ℃ |
Chemical Composition (Mass Fraction, Key Elements)
Chemical Symbol | Composition Range (%) | Chemical Symbol | Composition Range (%) |
Ni | 30.0-35.0 | Ti | 0.15-0.60 |
Fe | Balance | C | ≤0.10 |
Cr | 19.0-23.0 | Si | ≤1.0 |
|
| Mn | ≤1.5 |
|
| P/S | ≤0.03/≤0.015 |
|
| Cu | ≤0.75 |
Product Characteristics
1.Excellent High-Temperature Oxidation Resistance: Maintains stable oxide film formation at temperatures up to 870°C, resisting oxidation and scaling in air, steam, and weakly oxidizing atmospheres;
2.Anti-Carburization & Nitridation: The balanced Cr-Ni matrix inhibits carbon and nitrogen penetration, suitable for high-temperature carburizing or nitriding environments (e.g., industrial furnace internals);
3.Good Thermal Stability: Low thermal expansion coefficient and high creep strength, minimizing deformation under long-term high-temperature thermal cycling (critical for furnace tubes and heat exchangers);
4.Versatile Processability: Compatible with conventional hot/cold working (forging, rolling, bending) and welding; post-weld heat treatment optimizes mechanical properties for high-temperature service.
Metallographic Structure
At room temperature, it features a face-centered cubic crystal structure (austenitic matrix). Titanium addition refines grain size and prevents intergranular carbide precipitation, ensuring no brittle phase formation even after long-term high-temperature exposure.
Product Forms and Executive Standards
Product Form | Main International Executive Standards | Application Reference |
Plates/Strips | ASTM B409, EN 10088-2 | High-temperature furnace liners, heat exchanger shells |
Seamless Pipes/Tubes | ASTM B408, EN 10216-5 | Petrochemical cracking furnace tubes, power plant steam pipes |
Bars/Forgings | ASTM B407, EN 10269 | Furnace door frames, high-temperature fasteners, turbine components |
Wires | ASTM B408 (wire form), EN 10250-3 | High-temperature heating elements, welding filler wires for thermal equipment |
