Now that we are familiar with the structures of single chain macromolecules, we are in a position to look at some of the interactions of macromolecules with other macromolecules and with smaller molecules.
Corrosion on exposed metal. Corrosion is a natural process, which converts a refined metal to a more stable form, such as its oxide, hydroxide, or sulfide. It is the gradual destruction of materials (usually metals) by chemical and/or electrochemical reaction with their environment.
Crevice corrosion refers to the attack of metal surfaces by a stagnant solution in crevices, for example in nuts and rivet heads. When dust, sand and other corrosive substances are deposited on surfaces, they create an environment where water will accumulate and corrode the part. It can happen between two metals or between a metal and a nonmetal.