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Typical examples of uniform corrosion of aluminum alloys include the following: Corrosion in strong alkaline solutions. In strong alkaline solutions such as sodium hydroxide, the surface oxide film of aluminum alloys is uniformly dissolved, and the aluminum matrix continues to react to form aluminate; as a result, the entire surface thins at a similar rate. This represents the most typical scenario of uniform corrosion. The alkali washing process used for aluminum alloys in industry relies on this principle of uniform corrosion to carry out surface treatment. Corrosion in strong acid media: When aluminum alloys are exposed to non-oxidizing strong acids such as phosphoric acid, the surface passivation film cannot remain stable, and corrosion progresses uniformly across the entire surface. As the concentration of the acid and the temperature increase, the corrosion rate accelerates significantly, ultimately leading to a uniform reduction in the overall thickness of the component. Corrosion in alkaline seawater environments: In alkaline seawater with a high pH value, aluminum alloys such as 5083 and 1060 experience suppressed pitting corrosion; instead, uniform corrosion becomes the dominant form of corrosion, with the entire surface of the material being eroded uniformly. The corrosion rate increases as the pH value of the seawater rises. Post-corrosion in marine atmospheric environments: Aviation aluminum alloys such as 7B04, when exposed for extended periods to a marine atmosphere with high salt fog levels like that in Marishima, initially experience pitting corrosion; as time goes on, these pits become more numerous and smaller in size, and the corrosion process gradually shifts toward uniform corrosion, resulting in a uniformly distributed thin layer of corrosion across the entire surface. Corrosion in high-pH saline solutions: In a NaCl solution with a pH of >10 and an oxygen concentration of 3.5%, the passivation film of 7050 aluminum alloy is completely destroyed and cannot repair itself; neither intergranular corrosion nor stress corrosion occurs, and uniform corrosion takes place throughout the specimen.