The Domadia Group

This product group includes materials based on FeNi, FeNiCr and FeNiCo and feature a controlled thermal expansion with linear coefficients of expansion of nearly zero up to about 12 x 10-6/K within a determined temperature range.

The selected alloys have proven to be the standard alloys and cover the common area of sealing and expansion alloys of low thermal expansion.

Depending on the respective characteristic thermal expansion properties, the materials are suitable for bonding with hard and soft glasses or ceramics.

The criterion for such bond is that it must have a specific strength but only a minimum of internal stress and in many cases it has to be vacuum-tight.

Therefore it is required that the individual components, i.e. metal-glass or metal-ceramics, ideally have corresponding thermal expansion qualities.

The choice of alloys in this product group meets the whole range of known technical applications with regard to the requirements to sealing and expansion materials.

The materials have good forming properties, are cold workable and show a good deep drawing quality. Due to their strength characteristics, these alloys behave during metal cutting like austenitic steels. Welding and soldering are possible without particular difficulty.