Overall corrosion of nickel and its corrosion resistant alloys at high temperature F, CI −, HCI, HF, and BrF5 High-temperature fluorine—full corrosion (5)

Fluorine is the most powerful and most active halogen element. Its strongest oxidation potential makes it form compounds with all common elements. This property determines that it can react directly with the metal to form metal fluorides. The properties of the fluoride protective film are directly related to the metal’s resistance to fluorine corrosion. In low-temperature fluorine, Ni, Cu, Mg, and Fe can form a fluoride protective film, and therefore have suitable fluorine resistance. In the high temperature fluorine, Ni201 has the best corrosion resistance. Table 2-23 shows the corrosion resistance data of some metal materials in high temperature fluorine. It can be seen that Ni201 and Monel400 alloys have the best corrosion resistance in high temperature fluorine, copper oxide, ferritic stainless steel, austenitic stainless steel, Inconel 600 Carbon steel, etc., do not have suitable corrosion resistance at 400 oC fluorine.