Alloy 42,Low expansion 42 Alloy Tube,UNS K94100,E FORU

British Specs:，American Specs: ASTM F30 ASTM B 753 AMS 5683 Welding Wire，German Specs: WS 1.3917,DIN 17745 AFNOR NF A54-301

**PRODUCT DATASHEET: ALLOY 42 / LOW EXPANSION 42 ALLOY TUBE** **UNS K94100 - Precision Tubing Products** --- ### **1. OVERVIEW** **Alloy 42**, commercially known as **Low Expansion 42 Alloy**, is a specialized **nickel-iron alloy** containing precisely **42% nickel** that delivers an exceptionally **low coefficient of thermal expansion (CTE)**, engineered to perfectly match **borosilicate glass, alumina ceramics, and semiconductor materials**. Supplied in **precision tubing** form, this product offers exceptional dimensional stability for applications requiring minimal thermal expansion in tubular configurations. The alloy is registered under the Unified Numbering System as **UNS K94100**. --- ### **2. CHEMICAL COMPOSITION (Weight %)** | Element | Alloy 42 Tube Specification | UNS K94100 Requirements | |------------------|-----------------------------|-------------------------| | **Nickel (Ni)** | 41.0 – 42.5% | 41.0 – 42.5% | | **Iron (Fe)** | Balance | Balance | | **Manganese (Mn)**| 0.50 – 0.80% | ≤ 0.80% | | **Silicon (Si)** | 0.15 – 0.30% | ≤ 0.30% | | **Carbon (C)** | ≤ 0.05% | ≤ 0.05% | | **Chromium (Cr)**| ≤ 0.15% | ≤ 0.15% | | **Copper (Cu)** | ≤ 0.05% | ≤ 0.05% | | **Aluminum (Al)**| ≤ 0.05% | ≤ 0.05% | | **Sulfur (S)** | ≤ 0.015% | ≤ 0.015% | | **Phosphorus (P)**| ≤ 0.015% | ≤ 0.015% | --- ### **3. PHYSICAL & MECHANICAL PROPERTIES** | Property | Seamless Tube (Annealed) | Welded & Drawn Tube | |---------------------------------|--------------------------|---------------------| | **CTE (20–300°C)** | 4.5 – 5.5 × 10⁻⁶/°C | 4.5 – 5.5 × 10⁻⁶/°C | | **Density** | 8.11 g/cm³ | 8.11 g/cm³ | | **Melting Point** | 1420 – 1450°C | 1420 – 1450°C | | **Tensile Strength** | 500 – 600 MPa | 490 – 590 MPa | | **Yield Strength (0.2% Offset)**| 260 – 360 MPa | 250 – 350 MPa | | **Elongation (in 2")** | 30 – 40% | 28 – 38% | | **Modulus of Elasticity** | 145 GPa | 145 GPa | | **Hardness (Rockwell B)** | 65 – 80 HRB | 63 – 78 HRB | | **Electrical Resistivity** | 0.75 μΩ·m | 0.75 μΩ·m | | **Thermal Conductivity** | 14.5 W/m·K | 14.5 W/m·K | --- ### **4. INTERNATIONAL STANDARDS & EQUIVALENTS** | Standard Organization | Designation & Specification | |-----------------------|----------------------------| | **UNS** | K94100 | | **ASTM** | F30 (Alloy 42) | | **EN (European)** | 1.3917 (Ni42Fe) | | **ISO** | NiFe42 | | **JIS (Japan)** | C42N | | **GB (China)** | 4J42 | | **DIN (Germany)** | Ni42 | | **Tube Standards** | ASTM B725, ASTM B726 | --- ### **5. TUBE SPECIFICATIONS** #### **5.1 Seamless Tube** - **Outside Diameter**: 1.0 mm to 50 mm - **Wall Thickness**: 0.2 mm to 5.0 mm - **OD Tolerance**: ±0.05 mm - **Wall Tolerance**: ±10% - **Length**: 1.0 to 6.0 meters #### **5.2 Welded & Drawn Tube** - **Outside Diameter**: 3 mm to 80 mm - **Wall Thickness**: 0.3 mm to 4.0 mm - **OD Tolerance**: ±0.08 mm - **Wall Tolerance**: ±10% - **Weld Quality**: Fully annealed and normalized #### **5.3 Surface Finish & Condition** - **Surface Finish**: Bright annealed, pickled, or polished - **Straightness**: 1:1000 maximum - **Roundness**: Within OD tolerance - **End Finish**: Square cut, deburred, chamfered --- ### **6. PRODUCT APPLICATIONS** #### **6.1 Electronics & Semiconductor** - **Vacuum Tube Components**: Electron tube structural elements - **Semiconductor Process Tubes**: Gas distribution and wafer handling - **IC Packaging**: Lead frame and package structural tubes - **Thermal Management**: Heat exchanger and cooling tubes #### **6.2 Aerospace & Defense** - **Gyroscope Components**: Inertial navigation system tubing - **Avionics Cooling**: Electronic enclosure cooling tubes - **Radar Waveguides**: RF transmission tube components - **Sensor Housings**: Pressure and temperature sensor tubes #### **6.3 Medical & Laboratory** - **Analytical Instrumentation**: Spectrometer and chromatograph tubes - **Medical Device Components**: Precision medical instrument tubing - **Laboratory Apparatus**: Research equipment structural tubes - **Cryogenic Applications**: Low temperature instrument tubing #### **6.4 Telecommunications** - **Fiber Optic Components**: Alignment sleeves and structural tubes - **Microwave Devices**: Waveguide and resonator tubes - **Electronic Packaging**: Connector and housing components - **RF Components**: Antenna and transmission line elements --- ### **7. TECHNICAL SPECIFICATIONS** #### **7.1 Dimensional Standards** - **OD Control**: Precision honed and drawn to size - **Wall Uniformity**: Consistent wall thickness throughout - **Length Tolerance**: ±1.5 mm for cut lengths - **Concentricity**: 90% minimum wall concentricity #### **7.2 Temperature Performance** - **Cryogenic Service**: Maintains properties down to -196°C - **Room Temperature**: Optimal CTE matching range - **Elevated Temperature**: Service up to 400°C - **Thermal Cycling**: Excellent fatigue resistance #### **7.3 Fabrication Compatibility** - **Bending**: Minimum bend radius 2× OD - **Flaring**: Compatible with standard flaring tools - **Beading**: Suitable for bead forming operations - **Swaging**: Can be reduced or expanded as required --- ### **8. FABRICATION & PROCESSING** #### **8.1 Cutting & Machining** - **Cutting Methods**: Band saw, abrasive cutter, laser cutting - **Deburring**: Essential for all cut ends - **Machining**: Suitable for threading and grooving - **Cleanliness**: Critical for high-purity applications #### **8.2 Welding & Joining** - **Welding Process**: GTAW (TIG) and laser welding - **Filler Metal**: Matching composition recommended - **Joint Preparation**: Precision fit-up required - **Purge Gas**: Internal purge for quality welds #### **8.3 Bending & Forming** - **Bend Methods**: Mandrel bending for tight radii - **Springback**: Approximately 2-3 degrees - **Tooling**: Hardened tooling recommended - **Inspection**: Profile projection for verification --- ### **9. QUALITY ASSURANCE** #### **9.1 Material Certification** - **Chemical Analysis**: Certified spectrographic analysis - **Mechanical Testing**: Tensile and hardness certification - **Dimensional Report**: Full dimensional verification - **Surface Quality**: Per ASTM A480 requirements #### **9.2 Testing & Inspection** - **Eddy Current Testing**: 100% for defect detection - **Hydrostatic Testing**: Available for pressure applications - **Ultrasonic Testing**: For wall thickness verification - **Visual Inspection**: 100% surface examination #### **9.3 Cleanliness & Packaging** - **Cleanroom Packaging**: Class 1000 environment - **End Protection**: Plastic caps for both ends - **Surface Protection**: VCI paper or plastic sleeve - **Identification**: Permanent marking per specification --- ### **10. TECHNICAL ADVANTAGES** - **Exceptional Thermal Stability**: Maintains dimensions across temperature ranges - **Precision Dimensional Control**: Tight tolerances for critical applications - **Excellent Surface Quality**: Ideal for high-purity and vacuum applications - **Good Fabricability**: Can be bent, formed, and welded easily - **Superior CTE Matching**: Perfect for glass and ceramic interfaces - **Vacuum Compatibility**: Low outgassing characteristics --- **Note:** For critical applications involving high vacuum or ultra-high purity, special cleaning and passivation processes are recommended. Electropolished interior surfaces are available for semiconductor applications. Consult our technical team for specific application requirements and processing guidelines.

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 2460 gallon liquid totes Special package is available on request.