Kovar,Rodar Fittings,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® / Rodar® Fittings (UNS K94610)** #### **1.0 Product Overview** Kovar Fittings (commercially known as Rodar Fittings), designated as **UNS K94610**, are precision-engineered components manufactured from nickel‑cobalt‑iron controlled expansion alloy. These fittings are specifically designed for systems requiring reliable thermal compatibility with glass and ceramics, providing leak-tight connections in vacuum systems, electronic packages, and scientific instruments where dimensional stability across temperature cycles is critical. --- #### **2.0 Chemical Composition (wt%)** | Element | Content (%) | 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 castability | | **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 | 5.1 ×10⁻⁶/°C | 2.8 ×10⁻⁶/°F | 30–400°C | | 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 Typical Properties (Annealed)** - **Tensile Strength**: 520–590 MPa (75–85 ksi) - **Yield Strength (0.2% Offset)**: 350–420 MPa (51–61 ksi) - **Elongation**: 25–35% - **Hardness**: 68–82 HRB - **Impact Strength**: 40–60 J (30–44 ft-lb) **4.2 Pressure Ratings** - **Maximum Working Pressure**: 69 bar (1000 psi) at 20°C - **Test Pressure**: 1.5 × working pressure - **Temperature-Pressure Rating**: Per ASME B16.34 --- #### **5.0 Product Specifications** **5.1 Available Fitting Types** - **Butt Weld Fittings**: Elbows (45°, 90°), Tees, Reducers, Caps - **Socket Weld Fittings**: Unions, Couplings, Elbows - **Threaded Fittings**: NPT, BSPT, BSPP connections - **Flanged Components**: Blind flanges, Orifice flanges - **Special Fittings**: Crosses, Laterals, Adapters **5.2 Size Range & Dimensions** - **Size Range**: 1/8" to 4" NB (DN6 to DN100) - **Wall Thickness**: Schedule 5S to Schedule 80 - **Pressure Class**: 150# to 300# - **Dimensional Standards**: ASME B16.9, B16.11, B16.28 --- #### **6.0 Manufacturing Processes** **6.1 Production Methods** - Investment casting for complex shapes - Machining from forged or rolled stock - Precision grinding of sealing surfaces - Heat treatment in controlled atmosphere **6.2 Quality Control** - Liquid penetrant testing per ASTM E165 - Dimensional verification - Pressure testing - Material certification --- #### **7.0 Heat Treatment** **7.1 Solution Annealing** - Temperature: 850–900°C (1560–1650°F) - Atmosphere: Hydrogen or vacuum - 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 --- #### **8.0 Applications** **8.1 Vacuum & Semiconductor Systems** - High-vacuum chamber connections - Semiconductor process gas lines - CVD and PVD system fittings - Mass spectrometer connections - Electron microscope vacuum fittings **8.2 Aerospace & Defense** - Satellite propulsion system fittings - Space telescope vacuum connections - Radar system waveguide fittings - Cryogenic system components - Military electronic cooling systems **8.3 Scientific & Research Instruments** - Particle accelerator vacuum fittings - Nuclear research equipment - Laser system optical mounts - Laboratory vacuum system connections - Precision measurement instruments --- #### **9.0 International Standards** | Standard | Organization | Description | |----------|--------------|-------------| | **ASTM F15** | ASTM | Iron-Nickel-Cobalt Sealing Alloy | | **ASME B16.9** | ASME | Factory-Made Wrought Buttwelding Fittings | | **ASME B16.11** | ASME | Forged Fittings, Socket-Welding and Threaded | | **UNS K94610** | ASTM | Unified Numbering System | | **DIN 1.3981** | DIN | German Material Number | | **MIL-I-23011** | U.S. Military | Sealing Alloys | --- #### **10.0 Fabrication & Installation** **10.1 Welding Procedures** - **GTAW (TIG) Preferred**: Using matching filler wire - **Pre-heat**: Not required for thin sections - **Interpass Temperature**: Max 150°C (300°F) - **Post-Weld Heat Treatment**: Stress relieve at 425–540°C **10.2 Installation Guidelines** - Proper alignment during assembly - Use appropriate gasket materials - Avoid excessive torque on threaded connections - Follow prescribed tightening sequences **10.3 Glass & Ceramic Sealing** - Pre-oxidize surfaces before sealing - Controlled heating and cooling rates - Compatible with borosilicate glass - Suitable for alumina ceramic seals --- #### **11.0 Performance Characteristics** **11.1 Thermal Performance** - Excellent thermal expansion match with glass - Minimal thermal stress during cycling - Stable mechanical properties to 400°C - Good thermal shock resistance **11.2 Corrosion Resistance** - Good oxidation resistance - Suitable for high-purity gas service - Resists corrosion in vacuum environments - Compatible with ultra-high purity applications --- #### **12.0 Quality Assurance** **12.1 Testing & Certification** - **Pressure Testing**: Hydrostatic or pneumatic per applicable standard - **Non-Destructive Examination**: PT, RT, UT as specified - **Dimensional Inspection**: To ASME B16.9/B16.11 - **Material Certification**: EN 10204 3.1 with traceability - **Surface Finish**: Per customer requirements **12.2 Marking & Identification** - Material grade (K94610) - Size and pressure rating - Manufacturer's identification - Heat number for traceability --- Kovar/Rodar Fittings (UNS K94610) provide reliable performance in applications requiring exact thermal expansion matching with glass and ceramic components. Their ability to maintain dimensional stability and create leak-tight connections in temperature-varying environments makes them essential for critical vacuum, electronic, and scientific applications where conventional materials would fail due to thermal mismatch.

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 2386 gallon liquid totes Special package is available on request.