Invar Theoretical Data

(Also know as Invar 36, NILO 36, Pernifer 36, and Invar Steel)

Controlled expansion alloys such as Invar, Super Invar, Kovar (also know as ASTM F-15, NILO K, Pernifer 2918, Rodar, and Dilvar P1), 42 Alloy, 42-6 Alloy, 46 Alloy, 48 Alloy, and 52 Alloy are often used in applications where metals must form a hermetic seal with glass or ceramic. In order to prevent the glass or ceramic from cracking, the thermal expansion characteristics of the alloy must closely match the thermal expansion characteristics of the glass or ceramic to prevent undue stress as the material expands and contracts as the assembly is heated and cooled. Typical applications for hermetic seals include: vacuum tubes, lamps, power tubes, microwave tubes, transistors, switches and integrated circuits (Chips).

To access additional technical articles, theoretical papers, processing guides, manufacturers' data, and historical documents (listed below) and many other types of useful Information, please consult the Library of technical information that can be found here by following the Useful Controlled Expansion Alloys Information Link.

Invar and Controlled Expansion Alloy Article Index

General Information
Use of Fe 29NI 17Co in the Electronics Industry
How to Select The Proper Alloy for Glass and Ceramic Seals W.S Eberly
Invar and Elinvar Type Alloys
Westinghouse Kovar Brochure
High Strength and High Induction Co27-FE-C 0.23 Soft Magnetic Alloy for Forge Application Lin Li, Carpenter Technology
Historic Documents
Expansion Properties of Low-expansion Fe-Ni-Co Alloys Howard Scott
Invar and Elinvar: Nobel Lecture, Dec 11, 1920 Charles-Edouard. Gullaume
Ceramvar - US Patent Harry Clark Smith Jr.
Super Invar Patent
Patent Glass to Metal Seal Howard Scott
Theoretical Papers
A Survey of Theories About Invar
Glass to Metals Howard Scott
Physical & Mechanical Information
Data Sheet for Sealing Alloys - Assorted
Kover A from Alloy Digest
Dynamic Mismatch Between Bonded Dissimilar Materials
Electronic Thermal Management Using Copper Coated Graphite Fibers
Joining Kovar Alloy to Other Metal Brazing Welding Soldering
Process Information
Expansion Properties of Low-Expansion Fe-Ni-Co Alloys
Fluxless Soldering
From Technology to the Science of Glass Metal and Ceramic Metal Sealing
Gas Evolution from Plated Lids
Heat Sinks Carl Zweben and Kathryn A. Schmidt
Kovar - Cleaning of Oxidized Kovar Carborundum
Kovar - Conversion Factors Carborundum
Kovar - Expansion Curve Carborundum
Kovar - Glass Sealing Procedures Carborundum
Low Temperature Characterisitics Carborundum
Kovar - Machining of Kovar Alloy Carborundum
Kovar - Product Brochure Carborundum
Kovar - Recent Developments in Cleaning Carborundum
Kovar - Welding (Incomplete) Carborundum
Low Stress High Reliability Lids for Semiconductor Packages
Materials in Electronic Manufacturing Electronic
Packaging
Package Reliability as Affected by Material and Processes
Primer on Hermetic Sealing for Connectors
Sealing Glasses Materials Business
Temperature Thermal Expansion and Magnetorestriction of Kovar
The Printed Circuit Board Industry and Innovations for the 1990’s
The Properties of Suitable Metals
The Structural Integrity of Injection Molded F- 15 Alloy
The Use of Fe 29 NI 17 Co in the Electronics Industry
Soft Magnetic, Ferritic Stainless Steels for Electromechanical Devices Daniel A DeAntonio Carpenter Technology
Retail Theft Detection and the Alloys that Make them Work
Simplified Method of Selecting Soft Magnetic Alloys
Manufacturer’s Information Carpenter Technology
Glass Sealing Alloys Carpenter Technical Brochure
Mill Producers Information
Pernifer 36 - a.k.a Invar 36