Alloy 42 (Pernifer® 40, NILO® 42, Glass Sealing 42®)

Alloy 42 in Bar, Rod, Plate, Sheet, Strip, Coil | EFINEA

Alloy 42 (UNS K94100) is a nickel-iron alloy consisting of 41% nominal nickel, incidental cobalt and the balance iron.  It is classified as a controlled expansion alloy and is also referred to as a glass-to-metal or ceramic-to-metal sealing alloy.  Alloy 42 is also attributed to the following trade names:  CarTech® Glass Sealing 42 Alloy, NILO® 42, Pernifer® 42.


EFINEA is a leading global supplier of Alloy 42 in plate, round bar, rod, sheet, strip and coil.  Alloy 42 stock sizes are ready to ship and all forms are certified to conform to ASTM F30, MIL I 23011 Class 5 and AMS 23011 Class 5 specifications.


There is one current government specification covering these materials.  MIL I 23011 is an old, abandoned specification. It was superseded by AMS 23011 in 1998.  Alloy 42 is designated Class 5 in these specs.  To support customers with drawings and parts that reference these specifications, we ask our mill to melt and manufacture to these standards and state such on our test reports.


When you require Alloy 42 to your exact specifications, EFINEA capabilities include our in-house services to cut, slit, shear or centerless grind your order.  Talk to us about your specifications and alloy needs. Our experienced team will guide you through our product lines, in-house capabilities and competitive prices.


Alloy 42 is suited for applications where the thermal size change must be minimized during temperature variations and must be factored into the component design. The alloy is found in structural components for measurement and controls in which variations in expansion and contraction of temperature changes would negatively impact the accuracy of component.  When used for hermetic packaging, Alloy 42 is often flashed with nickel and then plated with gold. The purpose of this is to prevent corrosion and increase reliability.


The links below will navigate you to detailed information on the forms, sizes, properties, applications and a reference guide to machining Alloy 42.  Please contact us should you have any questions about any of our materials.

Glass Seal® is a registered trademark of CRS Holdings Ltd., Reading, PA, USA

NILO® is a registered trademark of Huntington Alloy Corp., USA.

Pernifer® is a registered trademark of VDM GmbH, Germany