Alloy 800HT (Welding),Incoloy 800HT Wire,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 (Wire & Welding Products) / UNS N08811** --- #### **1. Overview** **Alloy 800HT** (commercially known as **Incoloy 800HT**) is a nickel-iron-chromium superalloy specifically engineered for high-temperature applications. The "HT" designation indicates its optimized chemistry for enhanced creep rupture strength and superior resistance to oxidation and carburization compared to standard Alloy 800H. This datasheet focuses on two critical product forms: **Wire** (for fasteners, weaving, and fabric) and **Welding Products** (for joining and cladding). Both the wire and welding products conform to the **UNS N08811** specification and are characterized by a tightly controlled aluminum and titanium content, which is essential for their high-temperature performance. --- #### **2. Key Characteristics** * **Excellent High-Temperature Strength:** Superior creep and stress-rupture properties, vital for components and welds operating above 600°C (1112°F). * **Outstanding Oxidation & Carburization Resistance:** Withstands aggressive atmospheres in industrial furnaces and petrochemical processing. * **Good Fabricability:** The wire can be cold drawn and formed into various shapes, including fasteners and woven meshes. * **Thermal Stability:** Maintains microstructural stability and mechanical properties under prolonged thermal cycling. * **Excellent Weldability:** Can be readily joined using the matching **ERNiFeCr-1** filler metal to maintain corrosion and heat resistance in the weld zone. --- #### **3. Chemical Composition (Weight %)** The high-temperature performance is guaranteed by a precisely controlled chemistry. | Element | Minimum (%) | Maximum (%) | Key Function | | :--- | :--- | :--- | :--- | | **Nickel (Ni)** | 30.0 | 35.0 | Stabilizes the austenitic matrix and provides fundamental corrosion resistance. | | **Chromium (Cr)** | 19.0 | 23.0 | Forms a protective Cr₂O₃ scale for oxidation and corrosion resistance. | | **Iron (Fe)** | Balance | Balance | The base element of the alloy. | | **Carbon (C)** | 0.06 | 0.10 | Enhances high-temperature strength via carbide formation. | | **Aluminum (Al)** | 0.25 | 0.60 | Combined with Ti, provides strengthening and aids oxidation resistance. | | **Titanium (Ti)** | 0.25 | 0.60 | Combined with Al, it is critical for high-temperature strength. | | **Aluminum + Titanium (Al+Ti)** | **0.85** | **1.20** | **This is the defining requirement for 800HT (vs. standard 800H).** | | **Manganese (Mn)** | - | 1.50 | Improves hot workability. | | **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) | | **Electrical Resistivity** | 0.99 μΩ·m | --- #### **5. International Standards & Specifications** **Welding Products (Alloy 800HT Welding):** * **AWS A5.14 / SFA-5.14: ERNiFeCr-1** * This is the primary standard for bare wire and rod used in Gas Tungsten Arc Welding (GTAW/TIG), Gas Metal Arc Welding (GMAW/MIG), and Submerged Arc Welding (SAW). * **AWS A5.11 / SFA-5.11: ENiFeCr-1** * This standard covers covered electrodes for Shielded Metal Arc Welding (SMAW/Stick). **Wire Products (Incoloy 800HT Wire):** * **ASTM B408 / ASME SB408:** Standard Specification for Nickel-Iron-Chromium Alloy Rod and Bar. This is often the governing specification for wire rod and spooled wire. * **ASTM B166 / ASME SB166:** Standard Specification for Nickel-Chromium-Iron Alloy (UNS N06600, N06601, N06603, N06690, N06693, N06025, N06045, and **N08800**) Rod, Bar, and Wire. Note: This may cover 800HT under the N08800 grouping, but specific N08811 certification should be verified. * **AMS 5714:** A specific aerospace material standard for "Wire, Welding, 32Ni-21Cr- 46Fe (INCOLOY Alloy 800H)" which is applicable for high-integrity applications. **General Material Standard:** * **UNS:** N08811 * **EN (Euronorm):** EN 10095 (Heat resisting steels and nickel alloys) --- #### **6. Applications** **Welding Products (ERNiFeCr-1):** * Fabrication and repair of Alloy 800HT components in: * Steam Methane Reformer (SMR) components: outlet pigtails, manifolds, and reformer tubes. * Ethylene cracking furnace tubes and internals. * Power plant heat exchangers, superheater, and reheater tubing. * Cladding and overlay on carbon steel for corrosion resistance. **Wire Products (Incoloy 800HT Wire):** * **Fasteners:** High-temperature bolts, nuts, studs, and washers for furnace and reactor assemblies. * **Woven Wire Mesh:** Used for catalyst support grids, filtration baskets in high-temperature environments, and radiation shields. * **Welding Consumables:** The wire is the raw material for producing the **ERNiFeCr-1** welding filler metal. * **Electrical Resistance Heating Elements:** Suitable for certain types of heating appliances due to its oxidation resistance. * **Springs and Formed Wire Components:** For use in elevated temperature applications where consistent performance is critical. --- #### **7. Important Note on Heat Treatment** To achieve the specified high-temperature properties, Alloy 800HT **must** be solution annealed at a temperature of **minimum 1121°C (2050°F)**, followed by rapid cooling. This condition is a mandatory requirement for the wrought products and is essential for dissolving carbides and achieving the correct Al+Ti solution strengthening. Welds, by their nature, are cast structures and derive their properties directly from the filler metal chemistry. --- **Disclaimer:** This datasheet is for informational purposes. For design and procurement, always refer to the project-specific material requisition and the latest version of the relevant standards and certified mill test reports.

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 1935 gallon liquid totes Special package is available on request.