I. functions of hot galvanizing:
Hot dip galvanizing, also known as hot dip galvanizing, is one of the methods for chemical and electrochemical protection of steel and iron materials.Hot-dip galvanized corrosion protection: in humid air, in water containing carbon dioxide and oxygen, the surface of the galvanized layer will be covered with a white layer of mainly alkaline zinc carbonate. It's galvanizedPotentiometric ratio of iron and steel substrate potential (zinc potential value -0.76 v, iron potential -0.43 v)Low, so when the coating and the substrate form a primary battery, the zinc is eroded and the steel substrate is protectedProtection, this kind of protection is often called electrochemical protection.
2. Principle of hot galvanizing:
Hot galvanizing is different from electric galvanizing. Electrogalvanizing is in the process of electrolysis, so that the formation of zinc on the cathode!The coating. In fact, electroplating is a deposition process in which zinc atoms are deposited gradually. Namely in!At the beginning of electroplating, tiny nodules are formed on the surface of the iron base.The electroplating time increased and finally formed a plating layer. As opposed toOn the contrary, hot galvanizing is not a deposition process, but a dissolution process of zinc to iron, a molten zinc solution to iron,A coating formed by dissolution of.The formation of the pound holding layer is accomplished by the following steps: a. the surface of the iron base is dissolved by zinc solution. .ironIn the process of dissolution by zinc solution, ferrozinc alloy is formed and continues to diffuse. C. The surface of the fe-zn alloy layer is surrounded by the zn layer. Therefore, after decontamination and rust removal of steel materials, directly immersed in melting!The galvanized protective coating obtained from the zinc solution of zn is very firm. At the same time, its diffusion and covering ability is much better than electroplating.