Dumet wire   is the basic metal component of a   Lead-in-Wire   providing the required vacuum tight   glass-to-metal seal . Dumet consists of a base wire and a sheath. The ratio of both compounds should be in well-balanced proportions. Only then is it guaranteed to obtain a vacuum tight conductor through glass. This principle is used mainly in the lighting and diode production.

In order to produce   dumet wire , some key processes must be precisely controlled. In the set-up line, the cladding is realized: a Copper clad on a core wire (e.g. Nickel-Iron). This   Copper cladded wire   is welded to achieve an endless length and drawn to obtain the requested diameter. Finally the surface of the dumet has to be treated to guarantee a good adhesion to the glass. Depending on the application requirements this well-defined surface treatment can be done in either ways: Borating, oxidizing or nickel-plating.