Alloy 800HT (Welding),Incoloy 800HT Foil,Shim,N08811,E FORU

British Specs:BS 3072 BS 3073 BS 3074 BS 3075 BS 3076 NA15，American Specs:AMS 5766 Bar and Forgings AMS 5871 Sheet, Strip and Plate ASTM B408 ASTM B564 ASTM A240 ASTM A480，German Specs:WS 1.4876 WS 1.4958 WS 1.4959

### **Technical Datasheet: Alloy 800HT / Incoloy 800HT (Foil, Shim & Welding Products) / UNS N08811** #### **1. Overview** Alloy 800HT (commercially known as Incoloy 800HT) is a nickel-iron-chromium superalloy engineered for exceptional performance in high-temperature environments. The "HT" designation signifies its optimized chemistry for superior creep rupture strength and resistance to oxidation and carburization compared to standard Alloy 800H. This datasheet focuses on its specialized product forms: **welding filler metal**, and thin-gauge **foil** and **shim** stock. These product forms (Foil, Shim, Welding Wire) of **UNS N08811** are essential for high-temperature fabrication, sealing, and precision component manufacturing. #### **2. Key Characteristics** * **Excellent High-Temperature Strength:** Superior creep and stress-rupture properties, essential for thin foils and welds under load at temperatures exceeding 600°C (1112°F). * **Outstanding Oxidation & Carburization Resistance:** Withstands aggressive atmospheres in industrial furnaces and chemical processing environments. * **Good Ductility and Formability:** In foil form, it can be fabricated into complex seals and gaskets. * **Thermal Stability:** Maintains its shape and properties under prolonged thermal cycling, a critical property for shims. * **Weldability:** Can be readily welded with matching filler metal (ERNiFeCr-1) to maintain property integrity. #### **3. Chemical Composition (Weight %)** The high-temperature performance is defined by a tightly controlled chemistry, particularly the Aluminum and Titanium content. | Element | Minimum (%) | Maximum (%) | Key Function | | :--- | :--- | :--- | :--- | | **Nickel (Ni)** | 30.0 | 35.0 | Austenite stabilizer; provides base corrosion resistance. | | **Chromium (Cr)** | 19.0 | 23.0 | Forms a protective Cr₂O₃ scale for oxidation resistance. | | **Iron (Fe)** | Balance | Balance | Base element of the alloy. | | **Carbon (C)** | 0.06 | 0.10 | Enhances high-temperature strength. | | **Aluminum (Al)** | 0.25 | 0.60 | Combined with Ti, provides high-temperature strengthening. | | **Titanium (Ti)** | 0.25 | 0.60 | Combined with Al, crucial for creep strength. | | **Aluminum + Titanium (Al+Ti)** | **0.85** | **1.20** | **The critical, defining requirement for 800HT.** | | **Manganese (Mn)** | - | 1.50 | - | | **Copper (Cu)** | - | 0.75 | - | | **Silicon (Si)** | - | 1.00 | Enhances oxidation resistance. | | **Sulfur (S)** | - | 0.015 | - | #### **4. Physical Properties (Typical)** | Property | Value | | :--- | :--- | | **Density** | 7.94 g/cm³ (0.287 lb/in³) | | **Melting Range** | 1350 - 1400 °C (2460 - 2550 °F) | | **Thermal Conductivity** | 11.2 W/m·K (at 100°C) | | **Mean Coefficient of Thermal Expansion** | 14.4 μm/m·K (20 - 100°C) | | **Modulus of Elasticity** | 200 GPa (29 x 10⁶ psi) | #### **5. Product Forms & International Standards** **Alloy 800HT Welding Products:** * **Primary Standard:** **AWS A5.14 / SFA-5.14: ERNiFeCr-1** * This covers the bare wire used for Gas Tungsten Arc Welding (GTAW/TIG), Gas Metal Arc Welding (GMAW/MIG), and Submerged Arc Welding (SAW). * **Covered Electrodes:** **AWS A5.11 / SFA-5.11: ENiFeCr-1** * This standard covers coated electrodes for Shielded Metal Arc Welding (SMAW/Stick). **Incoloy 800HT Foil & Shim:** * **Foil & Shim Definition:** Typically, foil is considered a very thin sheet (often below 0.1 mm or 0.005 inches) supplied in rolls, used for wrapping, laminating, or as thin insulation. A shim is a thin piece of material, often supplied in sheets or pre-cut shapes, used to fill small gaps or spaces between components, such as in furnace and high-temperature engine assemblies. * **Applicable Standards:** * **ASTM B409 / ASME SB409:** This standard for Plate, Sheet, and Strip is the governing specification for the base material from which foil and shim stock are produced. * **AMS 5876:** A specific aerospace material standard for "Sheet, Strip, and Plate" of this alloy, often invoked for high-integrity applications. * **DIN 1.4959:** The common German material number for a similar grade. * **Typical Conditions:** Foil and shim stock are supplied in the solution-annealed condition to ensure optimal ductility and formability. **General Material Standard:** * **UNS:** N08811 #### **6. Applications** **Welding (Alloy 800HT Welding):** * Fabrication and repair of Alloy 800HT components in: * Petrochemical furnace components (reformer tubes, pigtails). * Power plant heat exchangers and superheater tubes. * Joining and overlay cladding for similar high-temperature alloys. **Foil & Shim (Incoloy 800HT Foil/Shim):** * **High-Temperature Gaskets & Seals:** Used in flanges, furnace doors, and expansion joints where resilience to heat and oxidation is critical. * **Thermal Management:** As a thin, heat-resistant radiation shield or thermal blanket in aerospace and heat-treating applications. * **Precision Spacers & Shim Stock:** In gas turbine engines, industrial furnaces, and chemical reactors to align components and maintain tolerances under thermal expansion. * **Heat Exchanger Spacers:** Used to maintain tube spacing in high-temperature exchangers. * **Vacuum Furnace Fixturing:** Due to its stability and low outgassing at high temperatures. #### **7. Fabrication Note** For **foil and shim**, post-production heat treatment is generally not required or practical due to the thin cross-section. Therefore, it is supplied in the final solution-annealed condition. **Welding** must be performed using the specified ERNiFeCr-1 filler metal to ensure the weld metal matches the base metal's high-temperature properties and corrosion resistance. --- **Disclaimer:** This information is for guidance purposes. For critical applications, always consult the specific material certification and the latest version of the relevant standards.

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 1934 gallon liquid totes Special package is available on request.