Corrosive protection mechanism of Zinc-rich coatings and application in coal mining equipment

Corrosive protection performance of self made inorganic Zinc rich primer coating (KD) and different corrosion protection coating systems KD+intermediate+finish paint (KDZY),commercial primer+intermediate+finish paint (ZYQT),KD+water based intermediate+finish paint (KDSX) and KD+commercial finish paint (KDSM) were tested and analyzed by salt spray,immersion,electrochemical tests and field experiment.The results show that the self-made inorganic Zinc-rich primer coating KD presents excellent corrosive protection in the salt spray test.Its corrosive protection mechanisms include cathodic protection,physical shielding and self-healing function.The KDZY and KDSX coating systems based on KD primer also have good corrosive protection in the salt spray test.The ZYQT and KDZY coating systems have good protection for Cl^- penetrating due to high resistor and better insulation.The ZYQT coating system manifests good corrosion protection in coal mining environment.All coating systems show poor water immersion resistance,so the coating systems are not suitable for a long time application in water immersion condition.