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Nuclear power plant power reactors have long been exposed to extreme working conditions of high temperatures of 310°C to 330°C, high pressures of 15.5MPa, strong radiation, and high-flow media. Corrosion is one of the core risks that affects their safe operation and has caused many major nuclear safety accidents. 1. Main corrosion type Irradiation-induced stress corrosion (IASCC): After core austenitic stainless steel and nickel-based alloys are irradiated by neutrons, defects such as dislocation loops and cavities will occur, causing grain boundary chromium depletion and hardening, which greatly increases the risk of stress corrosion cracking and is a key cause of failure of internal components in the reactor. Flow Accelerated Corrosion (FAC): The Fe₃O₄ protective film on the surface of the carbon steel/low alloy steel pipelines in the primary and secondary circuits is dissolved by the high-speed fluid, resulting in continuous thinning of the pipe wall. This is the main failure form of the secondary circuit pipelines and has caused many pipeline rupture accidents. Other typical corrosion: These include radiation embrittlement of reactor pressure vessels, intergranular corrosion/pitting corrosion of steam generator heat transfer tubes, chloride ion corrosion of seawater-related systems, subscale corrosion and hydrogen embrittlement of core fuel cladding, etc. 2. Core inducements and extreme working conditions: The coupling effect of high-temperature and high-pressure water/steam, strong neutron irradiation, and complex alternating stress greatly accelerates material aging. medium factor: Chloride ions in seawater, impurity deposition in the primary circuit coolant, and high flow velocity turbulence will all destroy the surface protective layer of the material. material itself: Materials such as low-chromium carbon steel and sensitized stainless steel have poor resistance to stress corrosion and flow-accelerated corrosion. 3. Detection and protection means Detection methods: Methods such as high-temperature autoclave simulated working conditions immersion weight loss test, slow strain rate stress corrosion test, electrochemical impedance spectroscopy analysis, and scanning electron microscope corrosion morphology observation are used to identify corrosion risks in advance. protective measures: Select high-chromium-nickel corrosion-resistant alloy as the heat transfer tube material, and optimize the pipeline structure to reduce turbulence mutation points ； Strictly control coolant pH and reduce dissolved oxygen content ； The seawater system uses titanium pipes and rubber-lined pipes with electrochemical protection to significantly reduce the corrosion rate.