Alloy 825,Incoloy 825 Rod,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 Rod / UNS N08825** --- #### **1. Overview** **Alloy 825** (commercially known as **Incoloy® 825**) is a nickel-iron-chromium alloy with additions of molybdenum and copper, specifically engineered for exceptional corrosion resistance in a wide range of aggressive environments. This datasheet specifically focuses on the **Rod** product form, which is widely used for machining components, fasteners, and valve parts. Stabilized with titanium to prevent sensitization, Incoloy 825 Rod offers excellent mechanical properties and corrosion resistance in both oxidizing and reducing media. The designations **Alloy 825**, **Incoloy 825 Rod**, and **UNS N08825** all refer to this versatile, corrosion-resistant nickel-base alloy in rod form. --- #### **2. Key Characteristics** * **Excellent General Corrosion Resistance:** Performs well in both oxidizing and reducing environments. * **Superior Resistance to Reducing Acids:** Outstanding resistance to sulfuric and phosphoric acids. * **Excellent Resistance to Stress Corrosion Cracking (SCC):** Highly resistant to chloride-induced SCC. * **Pitting and Crevice Corrosion Resistance:** The high molybdenum and chromium content provides strong resistance to localized attack. * **Good Machinability:** The rod form is suitable for machining into precision components. * **Stabilized against Sensitization:** The titanium addition prevents harmful chromium carbide formation during welding or high-temperature exposure. --- #### **3. Chemical Composition (Weight %)** The corrosion resistance of Alloy 825 Rod is derived from its carefully balanced chemistry. | Element | Minimum (%) | Maximum (%) | Key Function | | :--- | :--- | :--- | :--- | | **Nickel (Ni)** | 38.0 | 46.0 | Provides inherent resistance to corrosion and reducing environments. | | **Chromium (Cr)** | 19.5 | 23.5 | Confers resistance to oxidizing media (e.g., nitrates, oxidizing salts). | | **Iron (Fe)** | 22.0 min | Balance | The base element of the alloy. | | **Molybdenum (Mo)** | 2.5 | 3.5 | Enhances resistance to pitting, crevice corrosion, and reducing acids. | | **Copper (Cu)** | 1.5 | 3.0 | Provides resistance to reducing acids, particularly sulfuric acid. | | **Titanium (Ti)** | 0.6 | 1.2 | Stabilizes the alloy by forming TiC, preventing chromium carbide precipitation. | | **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 Rod Product)** * **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** **Rod Products (Incoloy 825 Rod):** * **ASTM B425 / ASME SB425:** Standard Specification for UNS N08825 Bar and Wire (This is the primary specification for rod products). * **ASTM B164 / ASME SB164:** Standard Specification for Nickel-Copper Alloy Rod, Bar, and Wire (Sometimes specified for 825). * **AMS 5871:** Aerospace Material Specification for bars, forgings, and rings. **General Material Standards:** * **UNS:** N08825 * **EN (Euronorm):** EN 2.4858 (NiCr21Mo) * **DIN:** 2.4858 * **ISO:** 6207 (For bar products) --- #### **7. Applications** Incoloy 825 Rod is widely used for machined components across various industries: * **Chemical Processing:** * Pump shafts, valve stems, fasteners, and agitators in sulfuric and phosphoric acid service. * Heat exchanger bolts and nuts for corrosive service. * **Oil & Gas Industry:** * Downhole tool components, valve trim, and stud bolts for sour gas (H₂S) service. * Machined parts for Christmas tree and wellhead equipment. * **Pollution Control:** * Scrubber system components, absorber tower bolts, and fastener systems. * Machined brackets and supports for flue gas desulfurization systems. * **Marine and Offshore:** * Propeller shafts, marine fastener systems, and pump components for seawater service. * Valve components for ballast and cooling water systems. * **Nuclear Industry:** * Fuel rod assembly components and processing equipment. --- #### **8. Fabrication Notes** * **Machining:** Alloy 825 Rod can be machined using methods similar to austenitic stainless steels but requires more power. Use positive rake angles, rigid setups, and sharp tools. * **Heat Treatment:** The rod is typically supplied in the solution annealed condition at **900-980°C (1650-1800°F)** followed by rapid cooling to ensure optimal corrosion resistance. * **Welding:** Can be readily welded using matching filler metals (AWS A5.14 ERNiFeCr-3) or electrodes (AWS A5.11 ENiFeCr-3). --- **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 1937 gallon liquid totes Special package is available on request.