Effects of Substrate Surface Properties on Organic Coating Adhesion of Pre-painted Steel Sheets

The organic coating adhesion is an important performance for pre-painted steel sheet. Based on the production statistic, the relationship between the organic coating adhesion and the types & source of substrate was confirmed. The surface properties of the substrate for pre-painted steel sheets were tested by means of electrochemical test and glow discharge spectrometer (GDS), and the influences of surface properties on the organic coating adhesion of pre-painted steel sheets were discussed. The results showed that the effects of the electrochemial activity of the substrate surface on the organic coating adhesion were obvious, and the electrochemical activity of substrate surface was correlated with the enrichment of alloying element Al on the substrate surface.