| Because of its excellent performance, ZTi60 alloy used in the manufacturing of ships increases sharply, but with the use of titanium and stainless steel,it is susceptible to cause significant galvanic corrosion. In this paper, micro-arc oxidation was used, a lot of testing for micro-arc oxidation process of ZTi60 alloy has done, Optimized electrolyte solution recipe for ZTi60 alloy, the corresponding micro-arc oxidation ceramic coating was prepared in the surface. Observation and analysis of available surface and cross section morphology of the film was done by SEM, phase structure of the coating composition was studied by X-ray diffraction (XRD). Analyzed of process parameters on growth characteristics, microscopic morphology, phase structure of the films. By the slope of polarization curves and Tafal analysis, AC impedance measurements and equivalent circuit fitting of ZTi60 alloy MAO coating, studied the corrosion resistance of the micro-arc oxidation surface. galvanic corrosion rate between ZTi60 alloy with different micro-arc oxidation coating and 321 stainless steel was studied by the immersion test in 3.5% NaCl solution. Through the standard galvanic corrosion test, with 321 stainless steel composition of the galvanic pair, compared with the galvanic corrosion properties of lack of micro-arc oxidation treatment ZTi60 alloy and different solution MAO treatment ZTi60 alloy, Tested galvanic current and galvanic potential of several films prepared under different conditions. The results show that:the ideal solution composition of micro arc oxidation for ZTi60 alloy:(1) 1-5 solution:Na2SiO316g/L, (NaPO3)614g/L, C6H5Na3O7 2g/L(2) 2-5 solution:NaAlO213g/L, (NaPO3)64g/L, NaF 1g/LSEM images of MAO coating of ZTi60 alloy show the surface of ceramic coating is composed of several similar "volcanic pile "-like porous;The acid-phosphoric acid solution treatment received more porous surface of ceramic coating, roughness larger, less dense, and the aluminum acid-phosphoric acid solution treatment received less porous surface of ceramic coating, roughness less but dense better; the film obtained in acid-phosphoric acid solution is thicker than the film obtained in acid-phosphoric acid solution.XRD analysis of the MAO coatings of ZTi60 alloy obtained, micro-arc oxidation coating obtained in the acid-phosphoric acid solution mainly composed of anatase TiO2 content of rutile TiO2 less, micro arc oxidation coating obtained in the aluminum acid-phosphoric acid solution mainly composed of Al2TiO5 phaseCompared to without MAO ZTi60 alloy, after ZTi60 alloy obtained MAO coatings on the surface, its corrosion potential moves to positive direction, anodic polarization increases, the corrosion current decreases, so the corrosion rate slows down, so that it improve its corrosion resistance, and after 1-5 solution treatment, the corrosion resistance of ZTi60 alloy sample become better; the corrosion model of ZTi60 alloy MAO coating in 3.5% NaCl solution is the uniform corrosion.Without micro-arc oxidation ZTi60 alloy and 321 stainless steel dual pair, the stainless steel is severe corrosion, corrosion rate is greater than 4g/dm2, after micro-arc oxidation treatment to ZTi60 alloys, the stainless steel corrosion have been alleviated, slowed down the corrosion rate; Under the same parameters, the ZTi60 alloy treated by the 1-5 solution made stainless steel corroded slower compared to the ZTi60 alloy treated by 2-5 solution, And the processing in the 1-5 solution for 20min, termination voltage is 400V, the corrosion rate of 321 stainless steel is reduced to 1g/dm2.Compared to without MAO ZTi60 alloy, after ZTi60 alloy was treated by MAO, constitutes galvanic pair with321 stainless steel, Galvanic current can be reduced an average of two thirds, almost the same galvanic potential. ZTi60 alloy by MAO treatment in 1-5 solution, dual access with 321 stainless steel,its galvanic corrosion level can be increased to A-level.
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