2,808
edits
Changes
no edit summary
===3.1.3 Weld Buttons===
For contacts used at higher temperatures, such as for example in controls for
stove tops, the use of contact rivets or the direct welding of silver based contact
materials on steel or thermo-bimetal carriers is usually not feasible. For such
applications weld buttons are suitable contact components.
Weld buttons are round or rectangular tips manufactured from clad contact bimetal
or in some cases tri-metal semi-finished materials. The surface layer is
produced from the specified contact material, the bottom weldable layer from a
material with higher electrical resistivity such as steel, nickel, or for example a
copper-nickel alloy. For precious metal savings a third high conductive layer of
copper may be inserted between the contact material and weld backing. To
improve the welding process the underside often has an embossed pattern with
one or more weld projections.
The manufacturing of weld buttons from bi– or tri–metal strip requires a ductile
contact material. Weld buttons with tungsten contact layers are therefore
produced by brazing of tungsten discs to a weldable pre-formed base.
*Typical contact forms of weld buttons
bild
*Contact materials
bild
*Carrier materials
bild
*Dimensional Ranges
bild
Equipment for the Production of Wires, Rivets and Miniature - Profiles
bild
*Quality criteria of standard weld buttons
bilder
===3.2 Manufacturing of Semi-Finished Materials===