Nickel Alloy 200, also known as UNS N02200 or WERKSTOFF NR. 2.4066, is a pure nickel alloy renowned for its robust mechanical properties across various temperatures and exceptional resistance to many corrosive substances, especially hydroxides. It withstands corrosion in acids and molten alkalis, even under reducing conditions.

In environments containing acid, alkaline, and neutral salt solutions, Nickel 200 products demonstrate good resistance. However, they are susceptible to severe attack in oxidizing salt solutions. At room temperature, it resists almost all dry gases, and it can handle dry chlorine and hydrogen chloride gases at temperatures up to 550°C.

Applications of Nickel 200 include manufacturing and handling of sodium hydroxide at temperatures exceeding 300°C, production of viscose rayon, soap manufacturing, production of aniline hydrochloride, chlorination of hydrocarbons like benzene, methane, and ethane, manufacturing of vinyl chloride monomer, and in reactors and vessels involved in generating and reacting fluorine with hydrocarbons.