AL 201™ Nickel Alloy, UNS N02201,DIN 2.4068, 1

### **Product Datasheet: AL 201™ / Nickel 201 (UNS N02201)** **A Low-Carbon Commercially Pure Wrought Nickel for High-Temperature and Corrosion-Resistant Applications** --- #### **1. Overview** **AL 201™**, commercially known as **Nickel 201** or **Alloy 201**, is a low-carbon version of commercially pure wrought nickel (99.6% minimum). Its key differentiator from Nickel 200 is its **very low carbon content** (0.02% max), which prevents the formation of embrittling graphite films at elevated temperatures. This characteristic makes Nickel 201 the preferred choice for applications involving continuous exposure in the temperature range of **315°C to 650°C (600°F to 1200°F)**, where standard Nickel 200 would become brittle. It retains all the beneficial properties of pure nickel—including excellent corrosion resistance, high thermal and electrical conductivity, and good magnetostrictive properties—while offering superior microstructural stability for high-temperature service. #### **2. Chemical Composition (Typical Weight %)** The composition is controlled to maximize high-temperature stability. | Element | Content (%) | Role in the Alloy | | :--- | :--- | :--- | | **Nickel (Ni)** | ≥ 99.0 | Provides the fundamental matrix for corrosion resistance, ductility, and conductivity. | | **Carbon (C)** | ≤ 0.02 | **Key Feature:** Kept very low to prevent embrittlement via graphite formation at high temperatures. | | **Copper (Cu)** | ≤ 0.25 | Residual element. | | **Iron (Fe)** | ≤ 0.40 | Residual element; kept low to maintain corrosion resistance. | | **Manganese (Mn)** | ≤ 0.35 | Aids in sulfur control and manufacturability. | | **Silicon (Si)** | ≤ 0.35 | Residual element. | | **Sulfur (S)** | ≤ 0.01 | Residual element, kept very low to improve hot workability. | #### **3. Physical Properties (Typical)** | Property | Value / Condition | | :--- | :--- | | **Density** | 8.89 g/cm³ (0.321 lb/in³) | | **Melting Point** | 1435-1445 °C (2615-2635 °F) | | **Thermal Expansion Coefficient** | ~13.3 μm/m·°C (20 - 100°C) | | **Thermal Conductivity** | ~70 W/m·K (at 100°C) | *[High]* | | **Electrical Resistivity** | ~0.096 μΩ·m | | **Modulus of Elasticity** | ~204 GPa (30 x 10⁶ psi) at 20°C | | **Magnetic Properties** | Essentially non-magnetic (< 1.01 μ) at 25°C in annealed state. | #### **4. Mechanical Properties (Typical for Annealed Condition)** **At Room Temperature:** * **Tensile Strength:** 380 - 485 MPa (55 - 70 ksi) * **Yield Strength (0.2% Offset):** 103 - 345 MPa (15 - 50 ksi) * **Elongation:** ≥ 40% **At Elevated Temperature:** Maintains good strength and excellent resistance to thermal shock and fatigue. #### **5. Corrosion Resistance & Key Characteristics** * **High-Temperature Stability:** Its primary advantage over Nickel 200; resists embrittlement up to 650°C (1200°F). * **Caustic Alkalis:** Outstanding resistance to all concentrations of sodium hydroxide (NaOH) and other strong alkalis, even at high temperatures. * **Neutral & Alkaline Salts:** Excellent resistance. * **Acids & Gases:** Good resistance to dilute hydrochloric and sulfuric acids, and excellent resistance to dry chlorine, hydrogen chloride, and fluorine at room temperature. * **Food & Pharmaceutical:** Non-toxic and non-contaminating, making it suitable for high-purity processing. #### **6. Product Applications** Nickel 201 is specified for applications where high purity, corrosion resistance, and high-temperature stability are simultaneously required: * **Chemical & Petrochemical Processing:** Caustic evaporators, reaction vessels, and transfer piping for high-temperature alkalis. * **Aerospace & Electronics:** Magnetostrictive devices, radar components, and aerospace structural components exposed to high temperatures. * **Electrical Engineering:** Electrical resistance welding electrodes, vacuum tube components, and other parts requiring high conductivity and thermal stability. * **Food Processing:** Equipment for high-temperature, high-purity processing. * **Fluorination Processes:** Equipment for handling elemental fluorine and fluorine-based compounds. #### **7. International and Industry Standards** Nickel 201 is covered by a comprehensive set of international and aerospace standards. * **UNS:** **N02201** * **DIN / Werkstoff Nr.:** **2.4068** * **ASTM Standards (U.S.):** * **ASTM B-162:** Standard Specification for Nickel Plate, Sheet, and Strip. * **ASTM B-160:** Standard Specification for Nickel Rod and Bar. * **ASTM B-161:** Standard Specification for Nickel Seamless Pipe and Tube. * **ASTM B-366:** Standard Specification for Factory-Made Wrought Nickel and Nickel Alloy Fittings. * **ASME Standards (U.S.):** * **ASME SB-162:** Plate, Sheet, and Strip (for pressure vessel construction). * **Aerospace Material Specification (AMS):** * **AMS 5533:** Sheet, Strip, or Plate, Corrosion and Heat-Resistant (Commercially Pure Nickel, Low Carbon). --- **Disclaimer:** The information provided herein is for reference purposes only. Properties can vary based on product form, size, and manufacturing process. Corrosion resistance is dependent on specific environmental conditions. For design and procurement, the official, latest issue of the relevant material specification must be consulted. "AL 201" and "Nickel 201" are trademarks of Huntington Alloys, a subsidiary of Special Metals Corporation.

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 3376 gallon liquid totes Special package is available on request.