Alloy 825,Incoloy 825 Pipe,UNS N08825,E FORU

British Specs:BS 3072 BS 3073 BS 3074 BS 3075 BS 3076 NA16，American Specs:ASTM B425 ASTM B424 ASTM B163 (Tube *)，German Specs:WS 2.4858

### **Technical Datasheet: Alloy 825 / Incoloy 825 Pipe / UNS N08825** --- #### **1. Overview** **Alloy 825** (commercially known as **Incoloy® 825**) is a nickel-iron-chromium alloy specifically engineered with molybdenum and copper additions for exceptional corrosion resistance in aggressive environments. This datasheet focuses on the **Pipe** product form, which is widely used for transporting corrosive fluids in chemical processing, oil and gas, and marine applications. The alloy's titanium stabilization prevents sensitization during welding, making it particularly suitable for fabricated piping systems. The designations **Alloy 825**, **Incoloy 825 Pipe**, and **UNS N08825** all refer to this corrosion-resistant nickel-base alloy in pipe form. --- #### **2. Key Characteristics** * **Excellent Corrosion Resistance:** Performs well in both oxidizing and reducing environments * **Superior Acid Resistance:** Outstanding resistance to sulfuric acid, phosphoric acid, and other reducing acids * **Excellent Stress Corrosion Cracking (SCC) Resistance:** Highly resistant to chloride-induced SCC * **Pitting and Crevice Corrosion Resistance:** Enhanced by molybdenum content (2.5-3.5%) * **Stabilized Against Sensitization:** Titanium addition prevents chromium carbide formation during welding * **Good Weldability:** Can be readily welded using matching filler metals --- #### **3. Chemical Composition (Weight %)** The corrosion resistance of Alloy 825 Pipe is ensured by its precise chemical balance. | Element | Minimum (%) | Maximum (%) | Key Function | | :--- | :--- | :--- | :--- | | **Nickel (Ni)** | 38.0 | 46.0 | Provides fundamental corrosion resistance in reducing environments | | **Chromium (Cr)** | 19.5 | 23.5 | Confers resistance to oxidizing environments | | **Iron (Fe)** | 22.0 min | Balance | Base element of the alloy | | **Molybdenum (Mo)** | 2.5 | 3.5 | Enhances pitting and crevice corrosion resistance | | **Copper (Cu)** | 1.5 | 3.0 | Provides resistance to reducing acids, particularly sulfuric acid | | **Titanium (Ti)** | 0.6 | 1.2 | Stabilizes against sensitization by forming titanium carbides | | **Carbon (C)** | - | 0.05 | Kept low to minimize carbide formation | | **Manganese (Mn)** | - | 1.00 | - | | **Sulfur (S)** | - | 0.03 | - | | **Silicon (Si)** | - | 0.05 | - | --- #### **4. Physical Properties (Typical)** | Property | Value | | :--- | :--- | | **Density** | 8.14 g/cm³ (0.294 lb/in³) | | **Melting Range** | 1370 - 1400 °C (2500 - 2550 °F) | | **Specific Heat (20°C)** | 440 J/kg·K | | **Thermal Conductivity** | 10.8 W/m·K (at 100°C) | | **Mean Coefficient of Thermal Expansion** | 14.0 μm/m·K (20 - 100°C) | | **Electrical Resistivity** | 1.12 μΩ·m | | **Modulus of Elasticity** | 196 GPa (28.4 x 10⁶ psi) | --- #### **5. Mechanical Properties (Typical for Annealed Condition)** * **Tensile Strength:** 655 MPa (95 ksi) min * **Yield Strength (0.2% Offset):** 275 MPa (40 ksi) min * **Elongation:** 30% min * **Hardness:** Rb 90 max --- #### **6. International Standards & Specifications** **Pipe Products:** * **ASTM B423 / ASME SB423:** Standard Specification for Seamless UNS N08825 Pipe * **ASTM B704 / ASME SB704:** Standard Specification for Welded UNS N08825 Pipe * **ASTM B163 / ASME SB163:** Standard Specification for Seamless Condenser and Heat-Exchanger Tubes * **ASTM B829:** Standard Specification for Seamless Nickel and Nickel Alloy Pipes **Dimensional Standards:** * **ASME B36.19M:** Stainless Steel Pipe (dimensional standard) * **ASTM B775/B776:** General requirements for nickel alloy pipe and tube **General Material Standards:** * **UNS:** N08825 * **EN (Euronorm):** EN 2.4858 (NiCr21Mo) * **DIN:** 2.4858 * **ISO:** 6207 (Nickel alloy pipes) --- #### **7. Applications** **Chemical Processing Industry:** * Acid production and handling systems (sulfuric, phosphoric acids) * Pickling tank heaters and piping systems * Chemical reaction vessels and transfer lines * Evaporator and crystallizer tubing **Oil & Gas Industry:** * Downhole production tubing in sour service (H₂S environments) * Process piping in refineries and petrochemical plants * Heat exchanger tubing for corrosive service * Seawater injection systems **Pollution Control:** * Flue gas desulfurization (FGD) systems * Scrubber piping and ducting * Waste acid recovery systems * Incinerator scrubber systems **Marine and Offshore:** * Seawater cooling systems * Ballast water piping * Chemical tanker piping systems * Offshore platform piping **Other Applications:** * Nuclear fuel reprocessing * Acid waste handling * Pharmaceutical processing equipment --- #### **8. Fabrication Notes** * **Welding:** Use matching filler metals (AWS A5.14 ERNiFeCr-3) for GTAW, GMAW, and SAW processes. Post-weld solution annealing is recommended for critical applications. * **Heat Treatment:** Solution anneal at **900-980°C (1650-1800°F)** followed by rapid cooling to maintain optimal corrosion resistance. * **Forming:** Can be cold formed using standard pipe bending equipment, accounting for its work-hardening characteristics. * **Cutting:** Can be cut using plasma arc, abrasive wheel, or saw cutting methods. --- **Disclaimer:** This technical information is for reference purposes. For critical applications, always consult the specific material certification and the latest version of the relevant standards. Actual properties may vary depending on manufacturing processes and heat treatment.

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 1939 gallon liquid totes Special package is available on request.