Dumet Wire 0.35mm Red Color Used as Sealing Material For All Kinds of Light Bulb

Ni 41~43%, Fe Balance

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.

Dumet wire consists of a nickel-iron core in an oxygen-free-high-conductivity copper sheath. It is available in various surface finishes: Electrically oxidised, borax coated, nickel plated, bare (uncoated).
Borated surface finish Dumet is used in Lead-in-wires for lamps. Dumet forms a glass-to-metal seal while manufacturing these lamps. The oxidised Dumet is used in Lead-in-wires, diodes and capacitor slug leads application.

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.

Dimeter 0.2mm-0.6mm

White dumet