1. Needs

Nuclear power plants utilize a wide variety of steels and alloys with different compositions and properties, ranging from the most sophisticated to the most conventional. We will now discuss those used in the nuclear boilers of pressurized water reactors operating in France, whose main components are the reactor vessel, the vessel internals, the pressurizer, the steam generators (SG), the primary motor-pump units (PMPU), and the associated components of the primary and secondary systems: piping, auxiliary pumps, and other pressure vessels (see [BN 3 270]