Invar 36,Super Invar 32-5 Wire,UNS K93603,E FORU

British Specs:，American Specs: ASTM F1684 MIL-S-16598 Tooling plate ASTM B388 Sheet & strip ASTM B753 K93050 Free-cut Invar，German Specs:WS 1.3912

**Super Invar 32-5 Wire (UNS K93603) - Technical Product Introduction** --- ### **Overview** **Super Invar 32-5 Wire** (UNS K93603) represents the wire form of the advanced iron-nickel-cobalt alloy, offering the lowest coefficient of thermal expansion among commercially available metal alloys in wire configuration. This product combines exceptional dimensional stability with excellent drawing characteristics, making it ideal for precision applications requiring thermal stability in linear and formed wire components. --- ### **1. Chemical Composition (%)** | Element | Content | |---------|---------| | **Nickel (Ni)** | 31.5-33.0 | | **Cobalt (Co)** | 4.5-5.5 | | **Iron (Fe)** | Balance | | **Carbon (C)** | ≤0.05 | | **Manganese (Mn)** | ≤0.50 | | **Silicon (Si)** | ≤0.20 | | **Phosphorus (P)** | ≤0.015 | | **Sulfur (S)** | ≤0.015 | | **Chromium (Cr)** | ≤0.15 | | **Aluminum (Al)** | ≤0.10 | --- ### **2. Physical Properties** | Property | Value | |----------|-------| | **Density** | 8.10 g/cm³ | | **Melting Point** | 1430°C | | **Coefficient of Thermal Expansion** | **0.5-0.8 × 10⁻⁶/°C** (20-100°C) | | **Thermal Conductivity** | 10.0 W/m·K | | **Specific Heat Capacity** | 500 J/kg·K | | **Modulus of Elasticity** | 147 GPa | | **Electrical Resistivity** | 0.80 μΩ·m | | **Curie Temperature** | 250°C | --- ### **3. Mechanical Properties** | Condition | Tensile Strength | Yield Strength | Elongation | |-----------|------------------|----------------|------------| | **Annealed** | 460-540 MPa | 260-330 MPa | 25-35% | | **Hard Drawn** | 600-740 MPa | 540-670 MPa | 8-15% | | **Stress-Relieved** | 500-600 MPa | 350-450 MPa | 15-25% | --- ### **4. Product Specifications** **Wire Diameter Range:** - **Fine Wire:** 0.025 mm to 0.50 mm - **Medium Wire:** 0.50 mm to 2.0 mm - **Coarse Wire:** 2.0 mm to 6.0 mm **Available Forms:** - **Spooled Wire:** Standard 1-25 kg spools - **Straight Lengths:** Cut to specific lengths - **Special Coatings:** Bare, tinned, or nickel-plated - **Temper Conditions:** Annealed, hard drawn, stress-relieved **Tolerances:** - **Diameter Tolerance:** ±0.001 mm to ±0.01 mm - **Roundness:** Within 50% of diameter tolerance - **Surface Finish:** Smooth, free from defects --- ### **5. Product Applications** **Advanced Electronics:** - **Precision Lead Wires:** For high-reliability semiconductor packages - **Bonding Wire:** Ultra-stable interconnects for quantum devices - **Resistance Wire:** Stable heating elements for precision instruments - **Spring Contacts:** Dimensionally stable electrical contacts **Precision Instrumentation:** - **Reference Wires:** Primary length standards for metrology - **EDM Wire:** Electrical discharge machining for precision components - **Optical Alignment:** Precision positioning and tensioning wires - **Measuring Wires:** Geodetic and survey reference wires **Aerospace & Defense:** - **Satellite Components:** Structural tension members and supports - **Avionics:** Stable wiring for sensitive electronic systems - **Optical Systems:** Precision alignment and mounting wires - **Cryogenic Applications:** Stable support wires at low temperatures **Medical & Research:** - **Medical Devices:** Precision components in surgical instruments - **Research Equipment:** Stable elements in scientific apparatus - **Implantable Devices:** Critical wire components - **Laboratory Instruments:** Precision mechanical elements --- ### **6. International Standards** | Standard Body | Standard Number | Description | |---------------|-----------------|-------------| | **ASTM** | ASTM F1684-06 | Standard Specification for Wire | | **UNS** | K93603 | Unified Numbering System | | **AMS** | AMS 7726 | Aerospace Material Specification | | **JIS** | JIS NCF 3 | Japanese Industrial Standard | | **GB** | GB 4J32 | Chinese National Standard | --- ### **7. Fabrication Characteristics** **Forming & Processing:** - **Bend Radius:** Minimum 2× diameter for hard wire - **Winding Characteristics:** Excellent for precision coil winding - **Springback:** Predictable and consistent - **Work Hardening:** Moderate rate, requires intermediate annealing **Joining Methods:** - **Welding:** GTAW (TIG) with matching filler metal - **Brazing:** Excellent with silver-based alloys - **Soldering:** Good compatibility with tin-based solders - **Resistance Welding:** Suitable for spot welding applications **Heat Treatment:** - **Solution Annealing:** 830-850°C, rapid cooling essential - **Stabilization:** 315-370°C for 30-60 minutes - **Stress Relieving:** 425-480°C after forming operations - **Atmosphere Control:** Hydrogen or vacuum recommended --- ### **8. Quality Assurance** **Testing & Inspection:** - **CTE Verification:** Dilatometer testing per ASTM E228 - **Dimensional Verification:** Laser micrometer control - **Surface Quality:** Microscopic examination - **Tensile Testing:** Regular mechanical property verification **Certification Requirements:** - **Material Certificate:** 3.1 Mill Certificate - **Traceability:** Full heat and spool traceability - **CTE Certification:** Actual test data for each lot - **RoHS/REACH Compliance:** Environmental compliance --- ### **9. Design Considerations** **Thermal Performance:** - CTE approximately 3× lower than standard Invar 36 wire - Optimal performance around room temperature - Requires thermal conditioning for critical applications - Excellent stability under thermal cycling conditions **Electrical Properties:** - Consistent electrical resistivity - Good solderability and bondability - Stable performance in varying temperatures - Suitable for high-frequency applications **Application Guidelines:** - **Storage:** Proper spool handling to prevent deformation - **Handling:** Clean conditions for sensitive applications - **Processing:** Appropriate annealing between severe forming operations - **Protection:** Corrosion protection in harsh environments --- ### **Conclusion** Super Invar 32-5 Wire (UNS K93603) offers unparalleled thermal stability in wire form, providing manufacturers with a premium material solution for the most demanding precision applications. Its exceptionally low coefficient of thermal expansion, combined with excellent drawing characteristics and consistent quality, makes it indispensable for advanced electronics, aerospace components, and scientific instrumentation where dimensional stability is critical. The material's superior performance, though requiring careful processing and quality control, justifies its use in applications where conventional materials cannot meet the stringent thermal stability requirements. Proper selection of diameter, temper condition, and adherence to recommended fabrication practices are essential for achieving optimal performance in precision wire components.

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 2429 gallon liquid totes Special package is available on request.