The metals are mixed to create some form of desirable property in the finished product. For example stainless steel which is an alloy of iron with chromium and vanadium prevents rusting. Other desirable properties include tensile strength, malleability (see malleable?), and ductility (see ductile?).
Other alloys include:
bronze
solder
pewter?
brass
[white gold]?
See also metallurgy
This page should be merged with Alloy