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Mechanical plating is an emerging surface engineering technology, because of its high efficiency, low cost, low energy consumption, simple process, environmental pollution, a cleaner production technologies and green manufacturing technology, widely attention at home and abroad, and in the actual production is more and more widely used. With the development of society and the lack of resources, the old mechanical plating single metal coating process can no longer meet the needs of people's production and life, the mechanical plating metal alloy plating process attaches great importance to. Kunming University of Science and Technology has successfully developed a mechanical zinc-aluminum, rare earth alloy plating process. On this basis, the purpose of this paper is to study the mechanical zinc-titanium alloy plating process and its coating the physical and chemical properties, and to analyze the role of mechanical the galvanized-based non-crystalline coating to form titanium ions. In this thesis, co-deposition of zinc, titanium metal adsorption phenomena and the results of preliminary analysis of the behavior of titanium role; orthogonal experiment to determine the mechanical plating Zn-Ti alloy production process; orthogonal experimental process plated titanium-containing mechanical galvanized base from 0 to 1.0% titanium coating, metal salts from a variety of sample random sampling brine immersion corrosion test, the neutral salt spray test, electrochemical corrosion test, atmospheric exposure test to determine the different components the coating resistant to chemical and electrochemical corrosion; through the bonding strength of the coating of the sample, the porosity, density and microhardness evaluation of the appearance, to determine the physical properties of the coating; while using a stereo microscope, fluorescence spectroscopy, scanning electron microscopy analysis of mechanical galvanized base surface morphology of the titanium coating, the coating element distribution and content, coating fracture morphology characteristics. To analyze the crystalline titanium ion mechanical galvanized base coating mechanism. Each set of experiments and test results show that: the the mechanical galvanizing base titanium alloy plating process is available; compared to the pure zinc coating, zinc titanium coatings have a stronger resistance to chemical corrosion and electrochemical corrosion, corrosion rate 55% or more, at the same time as the increase in the amount of titanium added, various coating corrosion resistance was first variable deterioration trend, wherein the corrosion resistance is most preferably Zn-Ti0.6% coating; zinc-titanium alloy coating the appearance of bright and smooth compared with the pure zinc coating, and the coating has a higher binding strength, density and microhardness value first increases and then decreasing its value with the increase in the amount of titanium added, wherein the Zn-Ti0.6% Coating combination of strength, density and microhardness; coating composition analysis and phase analysis shows, titanium present in the coating is equal to 86.18 ° 2theta only in 0.6% of the titanium-containing metal salts from the peak on the judgment of its existence, when Add an amount of 1.0%, measured when the titanium element relative content of 0.144%, the presence of titanium coating to the TiO 2 and TiO formed. Mechanical galvanized base titanium coating has good physical and chemical characteristics of titanium ions in the coating formation process played a role in the mechanism of: titanium metal salts to some extent, can be refined zinc powder algae groups in the bath, change zinc powder algal groups in the deposition of the workpiece surface, punctate deposits tend to be planar deposition is conducive to the formation of a uniform and dense coating; titanium can also change the resistance of the coating electrochemical corrosion characteristics, by pitting the form to the form of surface corrosion transformation;, titanium is highly resistant to corrosion, very stable in many media, titanium formed on the surface layer of dense, strong adhesion, inert oxide film on the metal substrate have good protection performance.
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