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→Clad Semi-Finished Pre-Materials (Contact-Bimetals)
800°C and clad (or “welded”) together under high pressure <xr id="fig:Hot_cladding_of_pre-materials"/> (Fig. 3.3). At the interface between the two materials a non-separable bond is formed by either diffusion of the reaction partners or in liquid phase by forming a AgCu eutectic alloy when an additional brazing alloy foil is placed between the two materials. Further processing is done by rolling with required annealing steps between subsequent thickness reductions. The disadvantage of this process is the usually limited short length of final material strips.
<figure id="fig:Hot_cladding_of_pre-materials">
[[File:Hot cladding of pre-materials (schematisch).jpg|right|thumb|Hot cladding of pre-materials (schematisch)]]
</figure>
In the ''Cold Roll-Cladding'' process the bond between the contact and carrier material is achieved by cold deformation of > 50% in one rolling pass ''<xr id="fig:Cold roll-cladding of semi-finished strips (schematic)"/> (Fig. 3.4)''. The high plastic deformation causes cold welding in the boundary layer between the two materials. To increase the quality and strength of the bond a subsequent diffusion annealing is performed in most cases. This process is most suitable for clad semi-finished strips with thin contact material layers (≥ 2 μm) and large strip length (> 100 m). Fig. 3.4: Cold roll-cladding of semi-finished strips (schematic)
<figure id="fig:Cold roll-cladding of semi-finished strips (schematic)">
[[File:Cold roll-cladding of semi-finished strips (schematic).jpg|right|thumb|Cold roll-cladding of semi-finished strips (schematic)]]
</figure>
*Typical configurations of clad contact strips bild(<xr id="fig:Typical configurations of clad contact strips"/>)
<figure id="fig:Typical configurations of clad contact strips">
[[File:Typical configurations of clad contact strips.jpg|right|thumb|Typical configurations of clad contact strips]]
</figure>
*Contact materials <br />Ag, Ag-alloys., Ag/Ni (SINIDUR), in special cases also Ag/CdO (DODURIT CdO), Ag/SnO<sub>2</sub> (SISTADOX), Ag/ZnO (DODURIT ZnO)<br />
*Carrier materials
<figure id="fig:Dimensions">
[[File:Dimensions.jpg|right|thumb|Dimensions]]
</figure>
When specifying the contact material layer thickness it is recommended to use the minimum required thickness.
