Nickel and nickel-base alloys are vitally important to modern industry because of their ability to withstand a wide variety of severe operating conditions involving corrosive environments, high temperatures, high stresses, and combinations of these factors.
There are several reasons for these capabilities. Pure nickel is ductile and tough because it possesses a face-centered cube crystal structure up to its melting point. Nickel has good resistance to corrosion in the normal atmosphere, in natural freshwaters and in deaerated non-oxidizing acids, and it has excellent resistance to corrosion by caustic alkalis.
Therefore, nickel offers very useful corrosion resistance itself and provides an excellent base for developing specialized alloys. Intermetallic phases can be formed between nickel and some of its alloying element: this enables the formulation of very high strength alloys for both low- and high-temperature service.