Incorporation of TiO2 in hot dip zinc coating for efficient resistance to biogrowth

The effect of incorporation of titanium dioxide on the physical, electrochemical and biocidal characteristics of hot dip galvanic coatings is studied with the aim of getting corrosion resistant galvanic coatings with least biogrowth when used in rough weather. Layer-wise analysis of the TiO2 incorporated galvanic coatings revealed segregation of the additive on to the coating surface. The segregated TiO2 increased the polarization resistance as evidenced from the ac impedance spectra and it resulted in low corrosion. The physical characteristics of the coatings were found to be improved by the TiO2 incorporation. The coating morphology was characterized by SEM analysis. The resistance of the coating against biogrowth was studied by quantifying the number of microorganisms on the coating surface after immersing to natural sea water containing microorganisms. (c) 2005 Elsevier B.V. All rights reserved.