Alloys used where metal parts must form a hermetic seal with glass or ceramic.
Leading applications include – Optical parts and equipment, lamps, vacuum tubes, etc.
Invar is a low expansion alloy, consisting of Nickel, and Iron. The Invar offers extremely low expansion characteristics teamed with very hig dimensional stability.
Few applications utilizing Ivnar –
Thermostats, Parts for Aerospace industry, Instruments and optical devices, Seals, spacers,
Invar forms – Bar, Sheet
Kovar is a low expansion alloy, consisting of Nickel, Cobalt and Iron.
It has good machining and dep drawing values.
Applications using Kovar includes -
Microwave and power tubes, Electronic components (transistors, diodes, etc) , Instrumentation, etc
Kovar forms available – Bar, Sheet