The mechanism of corrosion can be divided into three categories！
The mechanism of corrosion can be divided into three categories:
1. Chemical Corrosion
Chemical corrosion refers to the damage caused by the direct pure chemical interaction between the metal surface and the non-electrolyte. So, sulfur corrosion of metals in high-temperature gas and high-temperature oxidation of metals are chemical corrosion.
2. Electrochemical Corrosion
Electrochemical corrosion refers to the damage caused by the electrochemical reaction between the metal surface and the ionically conductive medium. And electrochemical corrosion is also the most common type of corrosion. Such as the corrosion of metals in the atmosphere, seawater, soil. And also various electrolyte solutions belonging to this category.
3. Physical Corrosion
Physical corrosion refers to the destruction of metals due to pure physical dissolution.
Its characteristics are: when the low melting point metal is dissolved into the metal material. It will have a “slicing” effect on the metal material. Since metals with low melting points are generally lower in strength, they will preferentially fracture under stress. This thus becomes a source of cracks for the metallic material. It should be said that this kind of corrosion is rare in engineering.
