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I. Uniform corrosion of conventional fuels: In fuel and gas boiler applications, after conventional fuels are burned, acidic substances in the flue gases condense on the metal surfaces when the temperature is below the acid dew point, resulting in uniform corrosion. This type of corrosion can be divided into scale corrosion and flue gas corrosion; it leads to a thinning of the boiler’s structure and a decrease in thermal efficiency. Pipeline transportation scenario: CO₂ and H₂S associated with conventional fuels dissolve in the condensate, creating an acidic environment; at temperatures below 60°C, a FeCO₃ film is formed, leading to widespread and uniform electrochemical corrosion. High-temperature flue gas scenario: The sulfur in conventional fuels burns to produce SO3, and within the sulfuric acid dew point range of 110–150°C, extensive and uniform sulfuric acid dew point corrosion occurs on metal surfaces. II. Uniform corrosion under high burnup: In nuclear fuel systems, high-burnup UO₂ fuel develops a large number of UO₂+x active sites at the grain boundaries in certain water environments. As burnup increases, the sensitivity of the anodic corrosion reaction also rises, making widespread uniform oxidation and dissolution more likely to occur. Fuel cladding system: Under high burnup conditions, the fuel element cladding exhibits mixed corrosion characteristics; at moderate temperatures, uniform corrosion predominates, with reactions occurring simultaneously across the entire metal surface, resulting in a uniform thinning of the cladding wall thickness. Long-term leaching behavior: In an underground water environment, after irradiation resulting in high fuel burnup, the elements U and Pu rapidly reach dissolution saturation, while the leaching rate of Sr-90 gradually decreases over time; overall, a uniform leaching pattern is observed on a long-time scale.