| The zinc-basic paint with high corrosion resistance technology was a new metal anticorrosion technology for iron and steel. Its applications in some fields such as automobile industry were getting increasingly common because of the advantages of less pollution, excellent anticorrosion property and non-hydrogen embrittlement. In this paper, the progress and current situation in research of the zinc-basic paint with high corrosion resistance technique and the specialty of the properties of the coating are introduced. The mechanism of formation of the passive zinc deposits and the zinc-basic coating with high corrosion resistance and the corrosion resistance mechanism were discussed. Moreover, zinc-basic coating was compared with the passive zinc deposits, so the superiority of corrosion resistance of the zinc-basic coating stood out.In this thesis, the flake zinc powder made by ourselves was adopted. CrO3 and K2Cr2O4 were blended in definite proportion to form the chromium acid component. The solvent, the emulsification agent, and the surfactants were blended to form the organic matter component. Then, flake zinc powder, the chromium acid component and the organic matter component were blended and mixed to receive zinc-basic paint with high corrosion-resistance. The Dip-spin processing was adopted and by drying and solidification gained the zinc-basic coating with high corrosion-resistance.The effects of different conditions on the corrosion resistance of zinc-basic coating were examined. The optimal conditions screened out were as follows: the time of mixing was one hour, the voltage of paint throwing off was 120V, the time of paint throwing off was about 30S, the temperature of drying was 805, the time of drying was 10-20min, the temperature of sintering was 280-300*C, and time of sintering was 20-30min. Under such conditions the syntheses properties of zinc-basic coating with high corrosion-resistance were the best. Additional, the pH of the chromium acid component was better during 0.8 and 2.8, and the pH of the finally paint during 4.5 and 6.0.By omnipotence metallography microscope, the surface and cross section morphologies .were analyzed. The result showed that: the whole coating was equality, the coating combined with metal substrates tightly, and the thickness of coating was equality.By different means of corrosion tester showed that: the thinner the zinc powder, the better the corrosion resistance of zinc-basic coating. The corrosion resistance of the zinc-basic coating was much better than the passive zinc deposits. In this experiment, the diameter of zinc powder was more than 5m but less than 10m, and the thickness was less than 0.5m. The content of zinc was controlled between 280 and 320g/L.By experiment, the mixture of CrO3 and K2Cr2O4 was much better than the pure CrO3 for the properties of zinc-basic coating. If the content was too high, the coating would separate out yellow CrO3 during the course of sintering, the corrosion resistance of the coating and the quality of surface became worse, the coating turned out green-yellow color, some zinc powder was brushed off from the coating, and the binding was inadequate. If the content of was lack, the adhesion among zinc powder and between zinc powder and the substrate were inadequate, some zinc powder was brushed off from the coating, and the color of the coating became black, pulverized. The content of zinc powder was controlled between 40 and 44g/L.The No. 3 solvent chose in this research was an aroma hydrocarbon solvent, and a latent solvent (an organic alcohol) was used meanwhile. Consequently, the paint dispersed very well, the coating was sleek, smooth, and sub-silver color. The more the content of the solvent, the more fine the corrosion resistance of the zinc-basic coating. The property of corrosion resistance of the coating was obviously improved when the content of solvent was up to 120g/L. So the content wasn't needed to increase, and it was 120g/L in this experiment.The reducing agent was vital to increase the corrosion resistance...
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