Forms of corrosion of metal materials

There are various forms of metal corrosion, which can be divided into uniform corrosion and localized corrosion. The schematic diagram of the main corrosion forms is shown in Figure 1-1.

The corrosion effect of uniform corrosion occurs uniformly on the entire metal surface, and gradually corrodes the metal on the plane and reduces its various properties. Uniform corrosion without obvious corrosion depth, such as rust on the surface of steel, white rust on the surface of clocks and aluminum

Localized corrosion can be subdivided into various forms of corrosion, mainly pitting corrosion, galvanic corrosion, crevice corrosion, erosion corrosion, selective corrosion, stress corrosion cracking, homogeneous corrosion and corrosion fatigue. Localized corrosion is an important form of corrosion in metal components. Although the total amount of metal loss is not large, severe localized corrosion often leads to sudden damage to equipment, resulting in huge economic losses, and sometimes even causes catastrophic accident.