Alloy 42 – Engineered for Precision and Stability

Alloy 42 is a nickel-iron controlled expansion alloy that closely matches the thermal expansion of ceramics and glass. It is widely used by Advanced Hermetic Solutions in critical hermetic applications where dimensional stability, magnetic shielding, and long-term reliability are essential.

Key Properties

  • Composition: ~41% Nickel, balance Iron
  • Density: 8.11–8.15 g/cm³
  • Melting Point: 1425–1435°C
  • Thermal Expansion: ~4.0 µm/m·°C (30–300°C)
  • Tensile Strength: 490–517 MPa
  • Yield Strength: 248–276 MPa
  • Electrical Resistivity: ~61–71 µΩ·cm
  • Curie Temperature: ~380°C

Applications in Hermetic Engineering

Glass-to-Metal Seals

Used in vacuum-tight seals where matching expansion coefficients between metal and glass are critical — such as aerospace and X-ray tubes.

Ceramic-to-Metal Brazing

Enables brazing with alumina or sapphire ceramics in sensor housings and aerospace-grade connectors.

Semiconductor & IC Packages

Maintains electrical insulation while offering structural support in hermetic chip carriers and ceramic leadframes.

Optoelectronic Assemblies

Used in laser housings and fiber optic feedthroughs for its stable, low-expansion characteristics.

Magnetic Shielding

Provides excellent low-frequency magnetic shielding, making it suitable for medical imaging equipment and sensor protection.

Vacuum Electronics

Used in sealed enclosures that maintain vacuum integrity under thermal cycling and stress.

Need Alloy 42 for Your Next Hermetic Project?

Contact Advanced Hermetic Solutions to discuss your material compatibility requirements, sealing processes, and delivery timelines.

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