Nanocrystalline Nickel,E FORU

### **Nanocrystalline Nickel (nc-Ni) - Advanced Metallic Material** #### **Overview** **Nanocrystalline Nickel** refers to nickel material with an ultra-fine grain structure where the crystallite size is typically less than 100 nanometers. This nanoscale microstructure fundamentally alters the material's properties compared to conventional coarse-grained nickel, resulting in exceptional mechanical strength, enhanced hardness, improved wear resistance, and unique physical characteristics. The material is typically produced through electrodeposition or severe plastic deformation methods, creating a high density of grain boundaries that dominate its behavior. --- #### **Chemical Composition (Weight % - Typical)** | Element | Content (%) | | :--- | :--- | | **Nickel (Ni)** | **≥ 99.0** | | **Sulfur (S)** | **≤ 0.005** | | **Oxygen (O)** | **≤ 0.1** | | **Carbon (C)** | **≤ 0.05** | | **Iron (Fe)** | **≤ 0.05** | | **Other Trace Elements** | **≤ 0.1** | *Note: High purity is essential for achieving optimal nanocrystalline properties. Some commercial grades may contain deliberate additions of grain growth inhibitors or strengthening elements.* --- #### **Physical & Mechanical Properties** | Property | Value / Description | | :--- | :--- | | **Density** | 8.85-8.92 g/cm³ | | **Grain Size** | **5-100 nm** (typically 20-50 nm) | | **Melting Point** | ~1440-1455 °C (slightly depressed due to nanoscale effects) | | **Microhardness** | **350-650 HV** (vs. 120-180 HV for conventional Ni) | | **Tensile Strength** | **900-1500 MPa** (vs. 300-500 MPa for conventional Ni) | | **Yield Strength** | **700-1200 MPa** (vs. 100-200 MPa for conventional Ni) | | **Elongation** | 1-10% (dependent on grain size and processing) | | **Young's Modulus** | 190-210 GPa (similar to conventional nickel) | | **Electrical Resistivity** | 8-15 μΩ·cm (higher than conventional Ni due to grain boundary scattering) | | **Thermal Conductivity** | 60-80 W/m·K (reduced compared to conventional Ni) | | **Coefficient of Thermal Expansion** | 12.5-13.5 × 10⁻⁶/°C | --- #### **Key Characteristics & Applications** **Key Characteristics:** 1. **Exceptional Strength-Hardness Combination**: Hall-Petch strengthening mechanism provides 3-5x strength increase over conventional nickel 2. **Enhanced Wear Resistance**: Superior resistance to abrasion and adhesive wear 3. **Thermal Stability Limitations**: Grain growth occurs at elevated temperatures (>250°C) 4. **High Corrosion Resistance**: Maintains excellent corrosion resistance of nickel with improved pitting resistance 5. **Unique Magnetic Properties**: Modified magnetic behavior due to nanoscale grain structure **Typical Applications:** - **Micro-electromechanical Systems (MEMS)**: Micro-gears, actuators, and sensors requiring high strength and precision - **Wear-Resistant Coatings**: Cutting tools, bearing surfaces, and industrial components - **Electronics Industry**: High-density interconnects, RF shields, and miniature components - **Aerospace Components**: Lightweight structural parts requiring high strength-to-weight ratio - **Medical Devices**: Surgical tools, implants, and diagnostic equipment components - **Energy Sector**: Fuel cell components, battery electrodes, and energy storage materials --- #### **Manufacturing Methods** | Method | Description | Typical Grain Size | | :--- | :--- | :--- | | **Electrodeposition** | Pulse or DC electroplating with organic additives | 10-50 nm | | **Severe Plastic Deformation** | High-pressure torsion, equal-channel angular pressing | 50-200 nm | | **Inert Gas Condensation** | Vapor deposition and consolidation | 5-30 nm | | **Mechanical Alloying** | High-energy ball milling | 10-100 nm | --- #### **International Standards & Specifications** | Standard Organization | Designation | Description | | :--- | :--- | :--- | | **ASTM** | **B955** | Standard specification for nickel-cobalt alloys coatings | | **ISO** | **NW 2200** | Nickel materials for advanced applications | | **MIL-PRF** | **Various** | Military specifications for electrodeposited nanocoatings | | **Research Standards** | **Custom Protocols** | Laboratory-specific processing and testing methods | | **Commercial Grades** | **Vendor Specifications** | Manufacturer-defined quality standards | *Note: Formal international standards specifically for bulk nanocrystalline nickel are still evolving, with most applications relying on proprietary specifications.* --- #### **Summary** **Nanocrystalline Nickel** represents a significant advancement in metallic materials engineering, offering extraordinary mechanical properties derived from its ultra-fine grain structure. While challenges remain in thermal stability and large-scale production, the material's exceptional strength, hardness, and wear resistance make it increasingly valuable for high-performance applications in microsystems, aerospace, medical devices, and advanced manufacturing. Continued research and development are expected to expand its commercial applications and establish more comprehensive international standards for this promising advanced material.

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 3213 gallon liquid totes Special package is available on request.