Nickel/gold surfaces are used whenever a conductive, corrosion resistant surface is important, as for example on key board contacts or on printed circuit board connectors. However, at high frequencies large losses because of the ferromagnetic characteristics of nickel are present. NiAu surfaces can be bonded, are suitable for storage and for multiple soldering processes. The thickness of the layer of gold plays an important role for the solder process. If it is too thick, phases rich in gold can be formed. The phases are brittle, and the solder joint will have low mechanical strength.