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Information × Registration Number 0203U008015, 0101U002788 , R & D reports Title Development of physico-chemical bases of creation of resourcesaving technologies of galvanic productions which providing of ecologycal protection from chemicals toxicants and security of Ukrainian water sources popup.stage_title Head Larin V.I., Registration Date 07-04-2003 Organization Kharkov National University named after V.N.Karazin popup.description2 The purpose of work is an establishment of regularities of etching process of copper and aluminium alloys in solutions of different structure. Methods: chronopotentiometry, gravimetry, spectrophotometry, X-rays analysis, electrothermography, microphoto, etc. Results: Kinetics of anodic dissolution of alpha-, beta-, and gamma- brasses in chloride solutions is in-vestigated It was established, what under dissolution of brasses in chloride solutions at first there is a selective dissolution of zinc on the mechanism non-stationary diffusion, super-vised volumetric diffusion of zinc in an alloy, which in due course passes in selective dis-solution connected to opposite deposition from etching of a copper solution, owing to what on a surface of a brass is formed copper enriched a layer rendering essential influ-ence on electrochemical and corrosion behaviour of a brass. At dissolution beta- brasses in the initial period (which duration depends on density of an anodi current) there is a uniform dissolution ofan alloy, which is sharply replaced by selective dissolution of zinc, that is zinc removing of an alloy. gamma- brasses are dissolved selectively with phase formation of copper since the first seconds. The dissolution of a brass L-62 in water-acetonytryl mixes is limited by a ca-thodic stage of process. The concentration areas of a unwater component are determined, for which prevailling processes are extraction of zinc and uniform dissolution of an alloy. The nature passiving of connections, for water solutions it of CuCl, CuOH and Zn, and for organic-aqueous, besides also Cu(OH)2 and Zn(OH)2 is established. The structure of fulfilled etching solution is determined. The influence of the different factors (temperature, concentration H2SO4 and contained in it of Al, duration of process, chemical structure of anodic layers) on dissolu-tion of aluminium alloys in a sulfuric acid is determined. Area of application: treatment processing of copper alloys both aluminium in mechanical engineering and instrument making. Product Description popup.authors popup.nrat_date 2020-04-02 Close