| Aiming at the shortages of solvent-containing coating such as environment pollution , resource waste, low shield ability of one pass daubing coating and short life of efficient protection. The present dissertation centers on the development of a new type of sacrificial solvent free coating containing Al-Mg-Zn alloy pigment.Due to its good properties of anticorrosion, epoxy is selected to be the vehicle of this coating. Varieties of hardeners and assistant agents for sacrificial epoxy coatings are discussed. Influence of PVC and thickness on coatings property is also studied by means of routine testing, potential monitoring and electrochemical impedance spectroscopy (EIS) measurement. The contrast tests of this coating in different media are performed. Protection mechanism of this new type of low PVC coatings is proposed.It is concluded that increase of PVC is advantageous to cathodic protection of the carbon steel matrix and shield effect of dissolution product of the pigment, but disadvantageous to barrier effect of coating system during its earlier exposure stage. Increase of coating thickness prolongs its efficient protection life in corrosive media. When PVC reaches 35%, Al-Mg-Zn alloy pigments are distributed in the coatings in semi-continuity state. It provides coatings with good dispersion properties, excellent shield effect and good cathodic protection.
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