Product Description

Sealing and expansion alloys Brief description 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 *2 x ***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, ***** 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. Applications The materials are mainly used for the manufacture of stamping, etching and deep drawing parts. An increased use in apparatus engineering and tool manufacture is noticed. Sealing alloys for hard glass and ceramics with expansion coefficients (*0 - **0 °C) of approx. 5.0 – 6.5 x ***6/K are used in the manufacture of: Electron tubes X-ray tubes Transmitting tubes TV pick-up tubes Kinescopes X-ray amplifiers Image sensors Rectifiers Protected contacts Feedthroughs Stamping, etching and deep drawing parts for semiconductors Receivers for solar collectors Insulators Sealing alloys for soft glass with expansion coefficients (*0 - **0 °C) of approx. 7.0 – *1.0 x ***6/K are used in the manufacture of: Switching tubes TV tubes Reed contacts Anode contacts Hermetically tight glass-seal feedthroughs Internal conductors of compression glass seals Expansion materials with expansion coefficients (*0 - **0 °C) of approx. 1.0 – 8.0 x ***6/K are used for the manufacture of: Thermostatic bimetals Expansion controllers Temperature controllers Measuring tapes Precision measuring instruments for geodesy and metrology Precision pendulums Parts for precision machine tools Anaesthetic machines