Custom Kovar CNC Machining Services | XML Precision Hardware Mfg
Looking for high-precision, vacuum-tight Kovar components? XML provides premium custom Kovar CNC machining services, renowned for its uniquely controlled thermal expansion that perfectly matches borosilicate glass and alumina ceramics. Utilizing advanced 3, 4, and 5-axis CNC technology, we manufacture complex, close-tolerance Kovar parts for optoelectronics, aerospace, defense, and medical electronics. From prototyping to high-volume production, XML delivers reliable, high-integrity hardware solutions.
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Why Choose Kovar for CNC Machining?
Kovar (ASTM F15 / UNS K94610) is a nickel-cobalt-ferrous alloy designed to be the ultimate material for applications requiring airtight, hermetic glass-to-metal or ceramic-to-metal seals. While notoriously tough to cut, XML’s advanced machining expertise unlocks its full potential:
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Controlled Thermal Expansion: Maintains a stable, low coefficient of thermal expansion (CTE) matching glass and ceramics from cryogenic temperatures up to 450°C.
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Exceptional Hermetic Sealing: Forms a tightly adherent oxide layer when heat-treated, ensuring uniform and vacuum-tight bonding for sensitive enclosures.
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High Structural Stability: Resists phase transformation at sub-zero temperatures, retaining its precision dimensions and mechanical properties in extreme environments.
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Excellent Magnetic Shielding: Offers good permeability at low magnetic fields, making it highly effective for protecting delicate electronic signals.
As a comprehensive hardware manufacturer, XML utilizes specialized rigid setups and custom tool geometries to conquer Kovar’s work-hardening tendency, delivering pristine parts with flawless precision.
Kovar Material & Machining Specifications
| Material Parameter | Technical Value / Specification | B2B Engineering Significance |
| Chemical Composition | Nominal: 29% Ni, 17% Co, 0.2% Mn, 0.2% Si, Bal Fe | Strictly controlled to guarantee precise expansion curves. |
| Density | 8.36 g/cm³ | Critical for structural weight calculations in aerospace. |
| Coefficient of Thermal Expansion (CTE) | 5.1 x 10⁻⁶ /°C (30°C – 400°C)6.2 x 10⁻⁶ /°C (30°C – 450°C) | Perfectly matches hard glass (like Pyrex) and Alumina ceramics to prevent thermal cracking. |
| Tensile Strength | 520 MPa (Annealed) / 750 MPa (Cold Rolled) | High structural integrity ensures parts withstand extreme mechanical stress. |
| Yield Strength | 340 MPa (Annealed) | High resistance to permanent deformation under load. |
| Thermal Conductivity | 17.3 W/m·K (at 20°C) | Stable thermal dissipation profile for sealed electronic components. |
| Curie Temperature | 435 °C | Retains its unique low-expansion properties up to this critical thermal point. |
| Machining Category | XML Production Capability | Manufacturing Details & Technical Tolerances |
| CNC Machining Processes | 3, 4, 5-Axis Milling, Swiss-Type Turning, Precision Drilling | Full capability for complex geometries and ultra-small micro parts. |
| Dimensional Tolerance | Down to ±0.005 mm (±0.0002 inches) | Micro-level accuracy suitable for tight-tolerance aerospace & medical seals. |
| Surface Roughness | Up to Ra 0.4 μm (16 μin) | Ultra-smooth finishes to optimize hermetic sealing surfaces. |
| Maximum Workpiece Size | CNC Milling: Up to 1000mm x 600mm CNC Turning: Up to Ø 350mm | Accommodates everything from micro-connectors to large structural housings. |
| Threading & Tapping | Blind holes, micro-threading, custom pitches | Specialized cutting feeds prevent Kovar from hardening during thread cutting. |
| Surface Finishing & Plating | Gold Plating, Electroless Nickel Plating, Passivation | Enhances solderability, wire bonding capability, and corrosion resistance. |
| Quality Control & Testing | CMM Inspection, Helium Leak Detection, Projector Measurement | 100% inspection available to ensure zero-defect vacuum integrity. |
Extensive Industry Applications of Kovar Parts
Aerospace
In modern aviation and satellite systems, electronic components are exposed to rapid, extreme temperature fluctuations. XML manufactures precision Kovar microwave carriers, satellite sensor housings, radar circuitry bodies, and guidance system enclosures. Our strict dimensional control ensures that the hermetic seals between metal housings and optical glass windows remain flawless, preventing vacuum loss in deep space.
Medical Devices
Biocompatibility, corrosion resistance, and absolute hermetic isolation are vital for clinical and diagnostic hardware. We utilize Swiss-type CNC machining to produce micro Kovar parts for X-ray tubes, implantable medical device cases, pacemaker connectors, and analytical laboratory instruments. XML guarantees pristine, burr-free finishes essential for medical cleanroom integration.
Robotics & Automation
Advanced automation systems operating in vacuum chambers or harsh industrial environments require robust protection for their sensors and optoelectronic encoders. XML delivers custom Kovar housings for high-end robotic vision systems, industrial automation sensors, and laser positioning modules. The thermal stability of Kovar prevents sensor drift, ensuring high repeatability and positioning accuracy for multi-axis robotic arms.
Automotive
As the automotive industry transitions to autonomous driving and high-power EVs, the demand for reliable power electronics and sensor modules has skyrocketed. XML provides Kovar components for high-temperature exhaust gas sensors, EV power inverter enclosures, and LiDAR glass-to-metal sealed arrays. Our high-efficiency manufacturing processes help automotive Tier-1 suppliers secure components that can withstand constant road vibration and thermal cycling.
Why Partner with XML for Your Kovar Machining?
When looking for a reliable machining supplier, you need more than just a workshop—you need a technically proficient, quality-driven partner.

Advanced Equipment
State-of-the-art Swiss CNC machines ensure exceptional precision, repeatability, and efficiency.

24/7 Engineering Support
Our engineers provide continuous technical support, from design review to production optimization.

Fast Turnaround
Streamlined workflows and dedicated project management enable quick and reliable delivery.

Competitive Pricing
Optimized processes and in-house production help customers save 30–40% without sacrificing quality.
Kovar CNC Machined Parts Gallery