Alloy 52,Glass sealing 52 Alloy Bar(Round bar, Flat bar),UNS N14052,E FORU

British Specs:，American Specs: ASTM F30，German Specs:

### **Alloy 52 (Glass Sealing 52) - Round Bar & Flat Bar Product Overview** **Alloy 52** is a nickel-iron controlled expansion alloy specifically engineered for matched sealing with specific borosilicate hard glasses. The **Round Bar** and **Flat Bar** forms provide versatile stock material for machining components requiring precise thermal expansion compatibility with hard glass in various high-reliability industrial applications. * **UNS Designation:** **N14052** * **Product Forms:** Round Bar, Flat Bar (Rectangular Bar) --- #### **1. Chemical Composition** Precisely controlled chemistry ensures consistent thermal performance in bar products. | Element | Percentage (%) | Role in the Alloy | |:---|:---|:---| | **Nickel (Ni)** | 51.0 - 52.5 | Determines thermal expansion characteristics | | **Iron (Fe)** | Balance | Base structural element | | **Manganese (Mn)** | 0.10 - 0.30 | Enhances hot workability during bar production | | **Silicon (Si)** | 0.10 - 0.30 | Improves glass wetting and sealing performance | | **Carbon (C)** | 0.05 max | Limited for optimal machinability and ductility | | **Sulfur (S)** | 0.02 max | Controlled impurity | | **Phosphorus (P)** | 0.02 max | Controlled impurity | --- #### **2. Physical Properties** Optimized properties for bar applications and hard glass sealing. | Property | Value / Condition | Notes | |:---|:---|:---| | **Density** | 8.25 g/cm³ (0.298 lb/in³) | | | **Melting Point** | ~1435 °C (2615 °F) | | | **Thermal Expansion Coefficient** | 20-300°C: 9.8-10.5 μm/m·°C
20-400°C: 10.2-10.8 μm/m·°C | Matches specific borosilicate glass types | | **Curie Temperature** | ~500 °C (930 °F) | Critical transition point for CTE characteristics | | **Thermal Conductivity** | 15.5 W/m·K at 20°C | | | **Electrical Resistivity** | 0.47 μΩ·m at 20°C | | | **Specific Heat** | 0.46 J/g·°C at 20°C | | --- #### **3. Mechanical Properties (Annealed Condition)** **Round Bar Properties:** * **Tensile Strength:** 530-600 MPa (77-87 ksi) * **Yield Strength (0.2% Offset):** 290-360 MPa (42-52 ksi) * **Elongation:** 30-40% in 2 inches * **Reduction of Area:** 45-60% * **Hardness:** 70-85 HRB * **Modulus of Elasticity:** 156 GPa (22.6 × 10⁶ psi) **Flat Bar Properties:** * **Tensile Strength:** 520-590 MPa (75-86 ksi) * **Yield Strength:** 280-350 MPa (41-51 ksi) * **Elongation:** 25-35% in 2 inches * **Hardness:** 68-83 HRB --- #### **4. Product Specifications & Applications** **Round Bar Specifications:** * **Diameter Range:** 3.0 mm to 300 mm * **Diameter Tolerance:** ±0.1 mm (<25 mm), ±0.2% (>25 mm) * **Straightness:** ≤1 mm per meter * **Surface Finish:** 3.2 μm Ra standard, 1.6 μm Ra available **Flat Bar Specifications:** * **Thickness Range:** 3.0 mm to 100 mm * **Width Range:** 10 mm to 300 mm * **Thickness Tolerance:** ±0.15 mm (<10 mm), ±1.5% (>10 mm) * **Width Tolerance:** ±0.5 mm (<50 mm), ±1.0% (>50 mm) **Primary Applications:** **Round Bar Applications:** * **Precision Machined Components:** Electrode pins, support posts, and structural elements for hard glass systems * **Hermetic Feedthroughs:** Single and multi-pin connectors for high-vacuum systems * **Optical Mounts:** Lens barrels and positioning components in scientific instruments * **Semiconductor Equipment:** Wafer processing components and chamber parts * **Medical Device Components:** Surgical instrument parts and implantable device elements **Flat Bar Applications:** * **Flanges and Base Plates:** Mounting surfaces for glass-to-metal assemblies with hard glasses * **Structural Frameworks:** Support elements in electronic packaging requiring CTE matching * **Heat Sink Bases:** Thermally compatible mounting platforms * **Machined Headers:** Multi-pin connector bases for electronic packages * **Instrumentation Components:** Precision frames and mounting brackets --- #### **5. International Standards** Comprehensive international specifications for bar products. | Standard Type | Standard Number | Title / Specification | |:---|:---|:---| | **ASTM** | **ASTM F15** | Standard Specification for Iron-Nickel Sealing Alloys | | **UNS** | **N14052** | Unified Numbering System Designation | | **AMS** | AMS 7723 | Aerospace Material Specification | | **ASTM** | ASTM B48 | Standard Specification for Rod and Bar | | **DIN** | DIN 1745 | Metallic Materials for Glass-to-Metal Seals | | **ISO** | ISO 9711 | Metallic Materials for Glass-to-Metal Seals | | **JIS** | JIS H 4541 | Iron-Nickel Alloy Bars for Glass Sealing | --- #### **6. Manufacturing & Processing** **Machining Characteristics:** * **Machinability Rating:** 40% (compared to 12114 steel) * **Recommended Tools:** Carbide or high-speed steel with positive rake angles * **Cutting Speeds:** 30-45 m/min for turning, 20-30 m/min for milling * **Feed Rates:** 0.1-0.3 mm/rev for turning, 0.05-0.15 mm/tooth for milling * **Coolant Requirements:** Essential for optimal tool life and surface finish **Heat Treatment:** * **Annealing:** 850-900°C in hydrogen or vacuum atmosphere * **Stress Relieving:** 650-750°C after heavy machining operations * **Cooling Rate:** Controlled cooling ≤100°C per hour through critical range **Surface Preparation for Glass Sealing:** * **Cleaning:** Degreasing and pickling to remove contaminants * **Plating Options:** Copper (1-3 μm) for improved glass wetting * **Pre-oxidation:** Controlled oxidation at 800-900°C in air atmosphere * **Surface Finish:** 0.8-3.2 μm Ra optimal for glass adherence --- #### **7. Quality Assurance** * **Chemical Certification:** Mill certificate with heat analysis * **Dimensional Verification:** Statistical process control for size and straightness * **Surface Quality:** Visual inspection and surface roughness measurement * **Mechanical Testing:** Tensile and hardness testing per ASTM E8 and E18 * **Metallurgical Examination:** Grain size assessment per ASTM E112 * **Traceability:** Full material traceability from melt to final product --- **Summary** **Alloy 52 (Glass Sealing 52) Round Bar and Flat Bar (UNS N14052)** provide essential stock materials for manufacturing precision components requiring reliable hard glass-to-metal seals with specific borosilicate glasses. Their controlled thermal expansion properties, excellent machinability, and consistent quality make them indispensable for applications in aerospace, medical devices, semiconductor equipment, and high-reliability electronic systems. The availability in both round and flat bar forms offers design flexibility for various component geometries while maintaining the critical thermal expansion matching with specific hard glass compositions. Compliance with **ASTM F15** and other international standards ensures consistent material performance and reliability in demanding applications where hermetic integrity and thermal cycle performance are paramount.

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 2510 gallon liquid totes Special package is available on request.