Alloy 825,Incoloy 825 Bar(Round bar, Flat bar),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 Bar (Round Bar & Flat Bar) / UNS N08825** --- #### **1. Overview** **Alloy 825** (commercially known as **Incoloy® 825**) is a nickel-iron-chromium alloy engineered with molybdenum and copper additions for exceptional corrosion resistance in aggressive environments. This datasheet specifically addresses the **Bar** product form, including **Round Bar** and **Flat Bar**, which serve as essential stock materials for machining, fabrication, and structural components in corrosive service. The alloy is stabilized with titanium to prevent sensitization, making it suitable for welded applications. The designations **Alloy 825**, **Incoloy 825 Bar**, and **UNS N08825** refer to this versatile nickel-base alloy supplied in bar form. --- #### **2. Key Characteristics** * **Excellent General Corrosion Resistance:** Suitable for both oxidizing and reducing environments. * **Superior Resistance to Reducing Acids:** Exceptional performance in sulfuric and phosphoric acids. * **Excellent Resistance to Stress Corrosion Cracking (SCC):** Highly resistant to chloride-induced SCC. * **Pitting and Crevice Corrosion Resistance:** Enhanced by molybdenum and chromium content. * **Good Machinability and Formability:** Suitable for precision machining and fabrication. * **Stabilized Against Sensitization:** Titanium addition prevents harmful chromium carbide formation. --- #### **3. Chemical Composition (Weight %)** The corrosion resistance of Alloy 825 Bar is ensured by its precise chemical balance. | Element | Minimum (%) | Maximum (%) | Key Function | | :--- | :--- | :--- | :--- | | **Nickel (Ni)** | 38.0 | 46.0 | Provides fundamental corrosion resistance and stability in reducing environments. | | **Chromium (Cr)** | 19.5 | 23.5 | Confers resistance to oxidizing media and general corrosion. | | **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 specific resistance to sulfuric and phosphoric acids. | | **Titanium (Ti)** | 0.6 | 1.2 | Stabilizes the alloy by forming titanium carbides, preventing sensitization. | | **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** **Bar Products (Round Bar & Flat Bar):** * **ASTM B425 / ASME SB425:** Standard Specification for UNS N08825 Bar and Wire (Primary specification for bars). * **ASTM B164 / ASME SB164:** Standard Specification for Nickel-Copper Alloy Rod, Bar, and Wire. * **AMS 5871:** Aerospace Material Specification for bars, forgings, and rings. * **DIN 2.4858:** German standard for NiCr21Mo alloy. **General Material Standards:** * **UNS:** N08825 * **EN (Euronorm):** EN 2.4858 (NiCr21Mo) * **ISO:** 6207 (For bar products) --- #### **7. Applications** **Round Bar Applications:** * **Shafting:** Pump shafts, mixer shafts, and marine propeller shafts. * **Fasteners:** Bolts, studs, nuts, and other high-strength corrosion-resistant fasteners. * **Valve Components:** Valve stems, trim parts, and gate valves. * **Machined Components:** Custom fittings, bushings, and bearings for corrosive environments. **Flat Bar Applications:** * **Structural Supports:** Brackets, clips, and supports in chemical processing equipment. * **Wear Strips:** Guides and wear surfaces in corrosive environments. * **Fabricated Assemblies:** Base plates, frames, and reinforcing elements. * **Heat Exchanger Components:** Baffles and support strips. **Industry-Specific Applications:** * **Chemical Processing:** Reactor components, agitators, and heat exchanger parts. * **Oil & Gas:** Downhole tools, wellhead components, and pipeline fittings. * **Marine:** Shipbuilding components, offshore platform parts, and seawater handling systems. * **Pollution Control:** Scrubber systems, waste treatment equipment, and flue gas ducting. --- #### **8. Fabrication Notes** * **Machining:** Use positive rake angles, rigid setups, and sharp tools. Recommended speeds are typically 30-50% slower than for stainless steels. * **Welding:** Employ matching filler metals (AWS A5.14 ERNiFeCr-3) or electrodes (AWS A5.11 ENiFeCr-3). Post-weld annealing may be required for optimal corrosion resistance. * **Heat Treatment:** Solution anneal at **900-980°C (1650-1800°F)** followed by rapid cooling to maintain corrosion resistance. * **Forming:** Can be cold formed using standard equipment, though it work-hardens more rapidly than carbon steel. --- **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 1938 gallon liquid totes Special package is available on request.