Alloy 475,Nilo 475 Pipe,UNS K95000,E FORU

British Specs:，American Specs:AMS 7718 Bar, Tube and Forgings MIL-N-14411 Comp 3，German Specs:

### **Alloy 475 (Nilo 475) - Pipe Product Overview** **Alloy 475**, commercially known as **Nilo 475**, is a nickel-iron-cobalt controlled expansion alloy specifically engineered for matched sealing with special hard glasses and certain ceramic materials. The **Pipe** form provides tubular components for applications requiring hermetic glass-to-metal or ceramic-to-metal seals in cylindrical configurations, offering both structural integrity and unique thermal expansion compatibility. * **UNS Designation:** **K95000** * **Common Names:** Nilo 475 Pipe, Glass Sealing 475 Pipe --- #### **1. Chemical Composition** Precisely controlled chemistry ensures consistent thermal performance in pipe form. | Element | Percentage (%) | Role in the Alloy | |:---|:---|:---| | **Nickel (Ni)** | 46.0 - 48.0 | Controls CTE characteristics | | **Cobalt (Co)** | 24.0 - 26.0 | Modifies thermal expansion properties | | **Iron (Fe)** | Balance | Base structural element | | **Manganese (Mn)** | 0.10 - 0.30 | Enhances manufacturability and hot workability | | **Silicon (Si)** | 0.10 - 0.30 | Improves glass/ceramic wetting performance | | **Carbon (C)** | 0.05 max | Limited for optimal welding and forming | | **Sulfur (S)** | 0.02 max | Controlled impurity | | **Phosphorus (P)** | 0.02 max | Controlled impurity | --- #### **2. Physical Properties** Specialized properties optimized for pipe applications and special material sealing. | Property | Value / Condition | Notes | |:---|:---|:---| | **Density** | 8.35 g/cm³ (0.302 lb/in³) | Higher due to cobalt content | | **Melting Point** | ~1445 °C (2635 °F) | | | **Thermal Expansion Coefficient** | 20-300°C: 7.8-8.5 μm/m·°C
20-400°C: 8.2-9.0 μm/m·°C | Matches special glass/ceramic expansion | | **Curie Temperature** | ~420 °C (790 °F) | Modified by cobalt addition | | **Thermal Conductivity** | 14.5 W/m·K at 20°C | | | **Electrical Resistivity** | 0.52 μΩ·m at 20°C | | | **Specific Heat** | 0.45 J/g·°C at 20°C | | --- #### **3. Mechanical Properties (Annealed Condition)** **Pipe Mechanical Characteristics:** * **Tensile Strength:** 530-600 MPa (77-87 ksi) * **Yield Strength (0.2% Offset):** 290-360 MPa (42-52 ksi) * **Elongation:** 20-30% in 2 inches * **Hardness:** 73-88 HRB * **Modulus of Elasticity:** 158 GPa (22.9 × 10⁶ psi) * **Burst Pressure:** Varies with wall thickness and diameter --- #### **4. Product Specifications & Applications** **Pipe Specifications:** * **Diameter Range:** 6 mm to 200 mm OD * **Wall Thickness:** 0.5 mm to 12 mm * **Length:** Standard 3-6 meters, custom lengths available * **Tolerance:** OD ±0.5%, Wall ±10% * **Surface Finish:** 3.2 μm Ra standard, 1.6 μm Ra available **Types Available:** * **Seamless Pipe:** For high-pressure and vacuum applications * **Welded Pipe:** Economical option for general applications * **Pre-oxidized Pipe:** Ready for immediate glass sealing * **Special Finished Pipe:** For ceramic sealing applications **Primary Applications:** **Electronics & Vacuum Applications:** * **Special Electronic Tube Envelopes:** Main structural bodies for unique glass systems * **Vacuum Chamber Components:** Specialized ports and connectors * **Microwave Tube Housings:** Components for specialized frequency applications * **Semiconductor Equipment:** Special process chamber components **Industrial & Scientific Applications:** * **Advanced Optical Systems:** Laser tube bodies for special applications * **Laboratory Equipment:** Specialized apparatus requiring unique CTE matching * **Sensor Housings:** Protection tubes for specialized sensors * **Ceramic Sealing Components:** Pipe forms for ceramic-to-metal applications **Aerospace & Defense:** * **Special Avionics Packaging:** Hermetic enclosures for unique applications * **Satellite Components:** Space-qualified packages with special requirements * **Military Electronics:** Specialized radar and communication components --- #### **5. International Standards** Comprehensive international specifications for pipe products. | Standard Type | Standard Number | Title / Specification | |:---|:---|:---| | **ASTM** | **ASTM F15** | Standard Specification for Iron-Nickel Sealing Alloys | | **UNS** | **K95000** | Unified Numbering System Designation | | **AMS** | AMS 7724 | Aerospace Material Specification | | **ASTM** | ASTM B829 | Standard Specification for Seamless Nickel Alloy Pipe | | **DIN** | DIN 1745 | Metallic Materials for Glass-to-Metal Seals | | **ISO** | ISO 9711 | Metallic Materials for Glass-to-Metal Seals | --- #### **6. Manufacturing & Processing** **Fabrication Characteristics:** * **Machining:** Good machinability with proper tool geometry and cooling * **Bending:** Capable of cold bending with minimum bend radius of 3x OD * **Welding:** Good weldability using TIG, plasma, or laser methods * **Flaring/Flanging:** Suitable for end preparation and connection interfaces **Sealing Preparation:** * **Surface Cleaning:** Critical removal of oils and contaminants * **Surface Activation:** Controlled oxidation for optimal bonding * **Thermal Cycling:** Controlled heating and cooling rates during sealing * **Sealing Temperature:** 900-1000°C for optimal glass/ceramic bonding **Quality Control:** * **Dimensional Inspection:** OD, wall thickness, and ovality verification * **Surface Examination:** Visual and microscopic surface quality assessment * **Leak Testing:** Helium mass spectrometry for vacuum applications * **Metallurgical Testing:** Grain structure and inclusion assessment --- #### **7. Design Considerations** **Wall Thickness Selection:** * **Thin Wall (0.5-1.5 mm):** For lightweight electronic envelopes * **Standard Wall (1.5-4.0 mm):** General purpose applications * **Heavy Wall (4.0-12.0 mm):** For high-pressure and structural applications **End Preparation:** * **Square Cut:** Basic preparation for simple seals * **Bevelled Ends:** For specialized sealing configurations * **Flanged Ends:** For mechanical attachment requirements * **Special Profiles:** Custom machined ends for specific applications --- **Summary** **Alloy 475 (Nilo 475) Pipe (UNS K95000)** provides a specialized tubular solution for applications requiring reliable sealing with special glasses and certain ceramics. Its unique thermal expansion properties, enhanced by cobalt content, combined with good manufacturability and consistent quality, make it essential for specialized electronic tubes, vacuum systems, optical devices, and advanced industrial equipment. The pipe form enables the creation of complex hermetic assemblies where special materials must be sealed to cylindrical metal surfaces, maintaining integrity under thermal cycling conditions. Compliance with **ASTM F15** and other international standards ensures material consistency and performance reliability for the most demanding specialized applications in aerospace, scientific, and advanced industrial sectors.

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 2524 gallon liquid totes Special package is available on request.