Alloy 801,Incoloy 801,UNS N08801，EFORU

### **Alloy 801 / INCOLOY® 801 (UNS N08801) - Technical Datasheet** --- #### **1. Overview** **INCOLOY® 801** is an austenitic nickel-iron-chromium alloy designed for high-temperature service in oxidizing and carburizing environments. This alloy combines excellent resistance to oxidation, carburization, and sulfur-bearing atmospheres with good high-temperature strength. Its balanced composition provides reliable performance in various industrial heating and processing applications up to 1100°C (2000°F). --- #### **2. Chemical Composition (Weight %)** The composition is optimized for high-temperature stability and corrosion resistance. | Element | Content (%) | Role & Benefit | |---------|-------------|----------------| | **Nickel (Ni)** | 30.0 - 34.0 | Provides austenitic matrix and high-temperature strength | | **Chromium (Cr)** | 19.0 - 22.0 | Confers oxidation and corrosion resistance | | **Iron (Fe)** | Balance | Base element providing cost-effective strength | | **Titanium (Ti)** | 0.75 - 1.50 | Stabilizes against sensitization and enhances strength | | **Copper (Cu)** | 0.75 max | Controlled residual element | | **Manganese (Mn)** | 1.50 max | Deoxidizer and sulfur control | | **Silicon (Si)** | 1.00 max | Enhances oxidation resistance | | **Carbon (C)** | 0.05 - 0.10 | Optimized for high-temperature strength | | **Aluminum (Al)** | 0.15 - 0.60 | Improves oxidation resistance | | **Sulfur (S)** | 0.015 max | Controlled impurity | *Note: "INCOLOY" is a registered trademark of Special Metals Corporation* --- #### **3. Physical Properties** The physical properties support high-temperature industrial applications. | Property | Value | |----------|-------| | **Density** | 7.95 g/cm³ (0.287 lb/in³) | | **Melting Point** | 1380-1425°C (2515-2600°F) | | **Specific Heat (20°C)** | 460 J/kg·K | | **Thermal Conductivity** | 12.5 W/m·K (at 20°C) | | **Mean Coefficient of Thermal Expansion** | 14.7 × 10⁻⁶/°C (20-300°C) | | **Electrical Resistivity** | 1.00 μΩ·m | | **Modulus of Elasticity** | 200 GPa (29.0 × 10⁶ psi) | | **Magnetic Permeability** | Essentially non-magnetic when annealed | --- #### **4. Mechanical Properties** The alloy maintains good mechanical properties at elevated temperatures. **Room Temperature (Annealed):** | Property | Value | |----------|-------| | **Tensile Strength** | 550-690 MPa (80-100 ksi) | | **Yield Strength (0.2% Offset)** | 240-380 MPa (35-55 ksi) | | **Elongation** | 30-45% | | **Hardness** | 75-90 HRB | **Elevated Temperature Properties (815°C/1500°F):** | Property | Value | |----------|-------| | **Tensile Strength** | 170 MPa (25 ksi) | | **Yield Strength** | 125 MPa (18 ksi) | | **Creep Rupture Strength (1000h)** | 45 MPa (6.5 ksi) | --- #### **5. Heat Treatment** **Annealing:** 980-1065°C (1800-1950°F) followed by rapid cooling **Stress Relieving:** 870-925°C (1600-1700°F) for 1 hour per inch of thickness --- #### **6. Product Applications** **INCOLOY 801** serves in various high-temperature industrial applications: - **Heat Treatment Industry:** - Radiant tubes and retorts - Furnace muffles and inner covers - Heat treatment baskets and fixtures - Carburizing and annealing equipment - **Chemical & Petrochemical:** - Ethylene cracking furnace tubes - Reformers and pyrolysis equipment - Catalyst support grids - High-temperature heat exchangers - **Power Generation:** - Heat recovery system components - Boiler parts and supports - Superheater tubes - Power plant furnace components - **Industrial Heating:** - Soaking pit covers - Lead pot fixtures - Salt bath equipment - Glass manufacturing components - **Pollution Control:** - Afterburner components - Incinerator parts - Exhaust system ducting --- #### **7. International Standards** The material conforms to various international specifications: | Standard | Specification | |----------|---------------| | **ASTM** | ASTM B408 - Nickel-Iron-Chromium Alloy Rod and Bar
ASTM B409 - Nickel-Iron-Chromium Alloy Plate, Sheet, and Strip
ASTM B407 - Nickel-Iron-Chromium Alloy Seamless Pipe and Tube | | **UNS** | UNS N08801 | | **ASME** | SB-408, SB-409, SB-407 | | **DIN** | DIN 17470 - NiCr32Fe | | **EN** | EN 10095 - NiCr32Fe | | **ISO** | ISO 6207 - NiCr32Fe | --- #### **8. Corrosion Resistance** - **Excellent** oxidation resistance up to 1150°C (2100°F) - **Outstanding** resistance to carburizing atmospheres - **Good** performance in sulfidizing environments - **Excellent** resistance to thermal cycling - **Good** resistance to nitrogen permeation - **Superior** performance in cyclic oxidation conditions --- #### **9. Fabrication Characteristics** - **Machining:** Similar to other austenitic nickel-chromium alloys - **Welding:** Excellent weldability using GTAW, GMAW, and SMAW methods - **Forming:** Good hot and cold working characteristics - **Forging:** Suitable for hot forging at 1050-1200°C (1920-2190°F) - **Annealing:** Requires rapid cooling from annealing temperature --- #### **10. Special Properties** - **Oxidation Resistance:** Forms protective chromium oxide scale - **Carburization Resistance:** Excellent performance in carburizing atmospheres - **Thermal Stability:** Maintains properties during long-term high-temperature exposure - **Cyclic Oxidation:** Good resistance to thermal cycling damage - **Temperature Capability:** Continuous service to 1150°C (2100°F) --- #### **11. Summary** **INCOLOY® 801 (UNS N08801)** represents a versatile nickel-iron-chromium alloy engineered for reliable performance in high-temperature oxidizing and carburizing environments. Its balanced composition provides an optimal combination of oxidation resistance, carburization resistance, and high-temperature strength, making it particularly valuable in heat treatment, chemical processing, and power generation applications. The alloy's ability to maintain structural integrity and corrosion resistance at temperatures up to 1150°C, coupled with excellent fabricability and weldability, establishes it as a preferred material for demanding thermal processing equipment. Governed by comprehensive international standards including ASTM B407-409 and ASME specifications, INCOLOY 801 continues to deliver cost-effective and reliable performance in various high-temperature industrial applications where oxidation resistance and long-term stability are essential requirements.

Packing of Standard Packing: Typical bulk packaging includes palletized plastic 5 gallon/25 kg. pails, fiber and steel drums to 1 ton super sacks in full container (FCL) or truck load (T/L) quantities. Research and sample quantities and hygroscopic, oxidizing or other air sensitive materials may be packaged under argon or vacuum. Solutions are packaged in polypropylene, plastic or glass jars up to palletized 1728 gallon liquid totes Special package is available on request.