Nickel and alloy steel tube nickel alloy materials are widely used in desulfurization industry, the main reason is that they not only have strong acid resistance, but also have strong corrosion resistance to halogen ions. The corrosion resistance of nickel alloys varies with the content of alloying elements.

Corrosion resistance of pure nickel the high corrosion resistance of pure nickel is due to its high price in the electrochemical metal sequence. The positive potential of nickel is higher than that of iron and copper with lower corrosion resistance. In addition, nickel is a "passivable" metal. As the polarization increases, the metal decomposition rate of the anode decreases due to the formation of a protective layer of oxides or hydroxides. The liquid nickel has a relatively high corrosion resistance to seawater, salt solution and other media whose corrosion rate is less than 0.1mm/a; Nickel is resistant to inorganic acids, such as sulfuric acid, phosphoric acid, hydrochloric acid, and some organic acids, such as acetic acid, formic acid, tartaric acid, only at temperatures below 50 ℃; Nickel has strong corrosion resistance to various concentrations of alkali solutions.

The passivation protection of nickel is enhanced by the addition of a small amount of copper. The nickel content of the alloy is very high and its corrosion resistance is comparable to that of pure nickel.