Kovar,Nilo-K Plate,UNS K94610,E FORU

British Specs:，American Specs: ASTM F15 ASTM F26 AMS 7726 Wire AMS 7727 Bar and Forgings AMS 7728 Sheet, Strip and Plate MIL-I-23011 Class 1，German Specs:WS 1.3981,AFNOR NF A54-301

**Technical Data Sheet: Kovar® / Nilo-K Plate (UNS K94610)** **1.0 Product Overview** Kovar Plate (also known as Nilo-K Plate), designated as **UNS K94610**, is a nickel‑cobalt‑iron controlled expansion alloy supplied in plate form. This specialized product maintains precise thermal expansion characteristics matching hard glass and ceramics, providing excellent dimensional stability and fabrication versatility for components requiring reliable thermal compatibility in electronic packaging, aerospace systems, and precision instruments. --- **2.0 Chemical Composition (wt%)** | Element | Content (%) | Primary Function | |---------|-------------|------------------| | **Ni** | 28.5–29.5 | Controls thermal expansion coefficient | | **Co** | 16.8–17.8 | Fine-tunes expansion match with glass/ceramics | | **Fe** | Balance | Base element | | **Mn** | 0.20–0.50 | Deoxidizer and improves workability | | **Si** | 0.10–0.30 | Deoxidizer and enhances rolling characteristics | | **C** | ≤ 0.02 | Minimizes carbide formation | | **Al** | ≤ 0.05 | Deoxidizer | | **P** | ≤ 0.02 | Impurity control | | **S** | ≤ 0.02 | Impurity control | --- **3.0 Physical Properties** | Property | Value (Metric) | Value (Imperial) | Condition | |----------|----------------|------------------|-----------| | Density | 8.36 g/cm³ | 0.302 lb/in³ | 20°C | | Melting Range | 1440–1460°C | 2624–2660°F | – | | Thermal Conductivity | 17.3 W/m·K | 120 Btu·in/(hr·ft²·°F) | 20°C | | Mean CTE (30–400°C) | 5.1 ×10⁻⁶/°C | 2.8 ×10⁻⁶/°F | Matching borosilicate glass | | Electrical Resistivity | 0.49 μΩ·m | 19.0 μΩ·in | 20°C | | Modulus of Elasticity | 138 GPa | 20.0 ×10⁶ psi | 20°C | | Curie Temperature | 435°C | 815°F | – | | Specific Heat | 0.46 J/g·°C | 0.11 Btu/lb·°F | 20°C | --- **4.0 Mechanical Properties** **4.1 Annealed Condition (Typical)** - **Tensile Strength**: 520–590 MPa (75–85 ksi) - **Yield Strength (0.2% Offset)**: 350–420 MPa (51–61 ksi) - **Elongation**: 25–35% - **Reduction in Area**: 45–60% - **Hardness**: 68–82 HRB - **Modulus of Elasticity**: 138 GPa (20.0 ×10⁶ psi) **4.2 Cold Rolled Condition** - **Tensile Strength**: 620–760 MPa (90–110 ksi) - **Yield Strength**: 550–690 MPa (80–100 ksi) - **Elongation**: 15–25% - **Hardness**: 85–100 HRB --- **5.0 Product Specifications** **5.1 Standard Plate Dimensions** - **Thickness**: 0.5 mm to 50 mm (0.020" to 2.0") - **Width**: 100 mm to 600 mm (4.0" to 24.0") - **Length**: 500 mm to 2000 mm (20" to 80") - **Thickness Tolerance**: ±0.05 mm for thickness < 3 mm - **Flatness**: 0.5 mm per 300 mm maximum **5.2 Available Conditions & Finishes** - Hot rolled, annealed, and pickled - Cold rolled, annealed - Ground finish (one or both sides) - Stress relieved condition - Special surface finishes available --- **6.0 Manufacturing Processes** **6.1 Production Methods** - Hot rolling from forged slabs - Cold rolling for improved surface finish - Annealing in hydrogen or vacuum atmosphere - Surface grinding and conditioning - Precision cutting and sizing **6.2 Quality Control** - Ultrasonic testing per ASTM A578 - Dimensional verification - Surface quality inspection - Mechanical property testing - Chemical composition analysis --- **7.0 Heat Treatment** **7.1 Solution Annealing** - **Temperature**: 850–900°C (1560–1650°F) - **Atmosphere**: Hydrogen or vacuum required - **Time**: 30–60 minutes at temperature - **Cooling**: Rapid cool to 400°C, then air cool **7.2 Stress Relieving** - **Temperature**: 425–540°C (800–1000°F) - **Time**: 60–90 minutes - **Atmosphere**: Protective atmosphere recommended - **Application**: After machining or severe forming --- **8.0 Applications** **8.1 Electronics & Semiconductor** - Microelectronic package bases and lids - Power semiconductor substrates - RF and microwave housing plates - Laser platform mounting plates - Crystal oscillator bases **8.2 Aerospace & Defense** - Satellite structural platforms - Avionics equipment mounting plates - Radar system base plates - Hermetic connector backplanes - Optical bench substrates **8.3 Industrial & Scientific** - Vacuum chamber wall sections - Precision instrument base plates - X-ray equipment mounting plates - Laboratory furnace components - Measurement equipment frames --- **9.0 International Standards & Specifications** | Standard | Organization | Description | |----------|--------------|-------------| | **ASTM F15** | ASTM | Iron-Nickel-Cobalt Sealing Alloy | | **UNS K94610** | ASTM | Unified Numbering System | | **DIN 1.3981** | DIN | German Material Number | | **AMS 7724** | SAE | Bars, Rods, and Wire Forms | | **JIS H 4551** | JIS | Japanese Industrial Standard | | **GB 4J29** | China | Chinese National Standard | --- **10.0 Fabrication Characteristics** **10.1 Machining Guidelines** - Good machinability in annealed condition - Use carbide tools with positive rake angles - Recommended cutting speed: 25–40 m/min - Use soluble oil coolants for improved finish - Moderate work hardening tendency **10.2 Forming & Cutting** - Good cold formability in annealed condition - Minimum bend radius: 2T (where T = thickness) - Suitable for shearing and punching - Laser and waterjet cutting effective - EDM machining possible **10.3 Welding & Joining** - Excellent weldability using GTAW process - Recommended filler: Matching Kovar wire - Pre-heat to 200–300°C for thick sections - Post-weld stress relief recommended --- **11.0 Performance Characteristics** **11.1 Thermal Performance** - Excellent expansion match with borosilicate glass - Minimal thermal stress during cycling - Stable dimensional characteristics to 400°C - Good thermal shock resistance **11.2 Glass Sealing Performance** - Pre-oxidize at 700–800°C for optimal bonding - Clean surfaces essential before sealing - Compatible with borosilicate glasses - Forms strong, hermetic seals --- **12.0 Quality Assurance** **12.1 Testing & Certification** - Chemical composition verification - Mechanical property testing - Ultrasonic testing for internal quality - Dimensional accuracy verification - Surface quality assessment **12.2 Documentation & Traceability** - Mill Test Certificates per EN 10204 3.1 - Full material traceability - Heat treatment records - Compliance with customer specifications Kovar/Nilo-K Plate (UNS K94610) provides exceptional thermal expansion matching capabilities in plate form, enabling the manufacture of components requiring exact dimensional stability and thermal compatibility. Its combination of precise thermal properties, good mechanical characteristics, and excellent fabrication versatility makes it the material of choice for critical applications in electronics, aerospace, and scientific instrumentation where reliable performance across temperature variations is essential.

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 2370 gallon liquid totes Special package is available on request.