The corrosion agent is a chemical substance, which is mainly used to control the corrosion rate of metal in the environment. It achieves its role by interference and slowing the electrochemical reactions between metal and environmental media. The following is the main mechanism of the corrosion agent:
A protective membrane: The corrosion agent forms a protective film on the metal surface to block the direct contact with the ambient medium. This protective film can be a substance adsorbed on the metal surface. If an organic acid or surfactant, it can also be a product generated by the chemical reaction with the metal surface, such as metal salt or oxides. This protective film plays a role in isolation metal and medium, reducing the corrosion rate of metal.
Reduce anode reactions: The corrosion agent can reduce the electrochemical response rate of the metal on the anode, thereby slowing the corrosion process. It can achieve this by inhibiting the catalyst or preventing electrons from being prevented by anode reactions. This can prevent the anode solubility of the metal surface and the release of metal ions.
Curcurus protection: The corrosion agent can be used as an external electron supply body, providing electrons to the metal surface to form local cathode protection. This can make the metal at a lower corrosion potential, thereby reducing the occurrence of corrosion reactions.
Forming complex: certain corrosion agents have the ability to replace, and can form a stable complex with metal ions. These complex can reduce the dissolution rate of metal, thereby slowing the corrosion of the metal.
In summary, the corrosion agent slows the corrosion rate of metal by forming a protective film, reducing anode reactions, providing cathode protection and forming complex. Different types of corrosion agents may adopt different mechanisms or combinations of various mechanisms to protect metal.