Contact system of any product requires deep
evaluation. Aluminum, copper and silver
which comprises of the major components of
the contact system have a tendency to form
a layer of oxide on being exposed to
atmosphere which contributes to their lack of
luster on visual inspection if left exposed.
Fretting corrosion phenomenon is an
obvious possibility. This is a form of
accelerated atmospheric oxidation which
occurs at the interface of contacting
materials which undergo cyclic relative
motions. In normal static contacts, contact
interfaces are formed by one or more
contact asperities at which metal to metal
contact has been established.