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Based on the basic classification of liquid metal corrosion discussed earlier, its core mechanism can be explained in detail through three types of actions: the physical dissolution mechanism, in which atoms from the solid metal diffuse directly into the liquid metal via the interface, with no chemical reactions involved; this process consists of two stages – surface dissolution and mass transfer as the material moves with the flow. In non-isothermal systems, elements dissolved in the high-temperature area will precipitate in the low-temperature area, triggering \"thermally driven mass migration\" which not only corrodes the material at the high-temperature end but may also block the pipelines at the low-temperature end. Chemical reaction mechanism: The solid metal components react with impurities such as oxygen, carbon, and nitrogen present in the liquid metal, resulting in the formation of corresponding oxides, carbides, and other products. If the resulting product is loose and prone to falling off, it will continue to accelerate the corrosion of the matrix ； If a dense and stable oxide film can be formed, it can actually serve as a barrier for protection; this is also the core principle of oxygen-controlled protection technology. Mechanisms of intergranular penetration and embrittlement: Due to the higher energy at grain boundaries and compositional segregation, liquid metal preferentially penetrates along these boundaries. This leads to the selective dissolution of elements at the grain boundaries; simultaneously, the low-melting-point liquid metal fills in these boundaries, forming weak phases that act as sources of cracks under stress, resulting in brittle fracture without significant deformation of the material and thereby significantly reducing the service safety of structural components. The corrosion rate of liquid metals is also influenced by factors such as temperature, fluid flow velocity, dissolved oxygen concentration, and the elemental composition of the material; the dominant mechanisms vary significantly depending on the specific situation.