Paint corrosion prevention mainly has the following three principles:
1, corrosion inhibition: some pigments, moisture or reaction products with film forming materials of anti-corrosion paint can inhibit or passivate the substrate metal, such as: phosphating primer, phosphating, galvanized chromium plating, epoxy zinc phosphate primer, etc.
2, shielding effect: the surface paint film of the anti-corrosion paint can prevent the corrosive medium from contacting the surface of the material, cut off the corrosion of the battery and the outside world, increase the resistance, some epoxy intermediate paint and part of the top paint is this principle
3, cathodic protection: the electrode potential of the anti-corrosion paint film is lower than that of the substrate metal, and it can be offset as an anode in the corrosion battery, so that the cathode surface is protected. Zinc-rich primers work this way
Therefore, in order to do a good job of anticorrosion, it is necessary to integrate these three corrosion principles, and according to the requirements of the site environment, a customized anti-corrosion coating system with the selection of the formula, coupled with good site construction, can achieve effective anti-corrosion.
Metal corrosion is mainly caused by the metal surface interacting with oxygen in the air in a humid environment to produce a loose oxide layer, and the effect continues. If the metal surface is coated with paint, the metal surface can be completely covered, so that it can not contact moisture and air, so as to achieve the effect of corrosion prevention.