ABSTRACT
Coating metals belonging to this category are copper, silver, platinum, gold, and their alloys. As was shown in Table 1.1, the standard single potentials of these metals are more noble than those of hydro gen. So, the oxidizer in corrosion cells, formed on these metals in a natural environment containing no other particular oxidizers, is a dissolved oxygen. Therefore, the electromotive force that causes corrosion is so small that coating with noble metals is effective for corrosion protection. As most of these metals are precious, they are used mainly for purposes such as decorative appearance and electri cal conduction.
