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Information × Registration Number 0305U003896, 0104U008306 , R & D reports Title Investigation of surface processes by chemical and electrochemical dissolving of copper and its alloys in various solutions. popup.stage_title Вивчення поверхневих процесів при хімічному і електрохімічному розчиненні міді і її сплавів в різних розчинах. Head Larin V., Registration Date 01-11-2005 Organization Kharkov National University named after V.N.Karazin popup.description2 The aim of the investigation - to study surface processes passes on copper and its alloys sur-face by their electrochemical and chemical dissolving in various aqueous and aqueous-organic solutions.Methods: gravimetry, atom absorption spectrometry, X-rays, chronopotentiometry. Corrosive and electrochemical behaviour of Cu-Ni alloys in aqueous acidic chloride-contained and ammoniac solutions, anodic dissolving of Fe- Cu alloys in aqueous electrolytes of NaCl, NaOH and their mixtures, corrosive and anodic behaviour of brass L-62 in concentrated aqueous solutions of FeCl3, CuCl2 and their mixtures as well as in chloride-contained acetonitrile solutions and its mixtures with water have been investigated. The kinetics of copper dissolving in chloride-contained solutions is studied.In the area of active copper dissolving have been shown takes place its ionization into Cu(I). Species of ionization products depends on Cl- -ions concentration. Active Cu dissolving passes through the formation of CuCl adsorption adsorption layer that dissolve in Cl- -ions ex-cess with CuCl2- complexes formation. The active cathodic copper dissolving has been shown is limited by diffusion and kinetics. The velocity of CuClj1-j flow is determinated only by diffu-sion. In the area of limited current on the copper surface is formated also the adsorption CuCl layer that transform then in porous crystalline CuCl layer. In this potentials area CuClads can also ionize with Cu2+ -ions formation. The thickness of phase CuCl layer have been founded depends on Cl- -ions concentration. The process of copper dissolving in the range of limited current have been proofed is limited by Cl- -ions diffusion through the pores of surface layer. The velocity of copper passivation with CuCl is evaluated by the current difference on the disc and the ring. Amines and iodid- (bromid-) ions have been shown are promote the increase of capacity of solutions by etched copper and ensure sufficient high etching velocity during all period. Multilayer copper passivation in aqueous and aqueous-ammoniac copper-chloride solu-tion is studied. The increase of layers conductivity because of border Cl- -ions diffusion and their concentrating in polycrystalline precipitates are registrated. This effect have been estab-lished is enhanced by increase of porosity degree, frequentative scan of potential as well as be the possibility of counter Cu2+-ions diffusion. The Fe-Cu alloys passivation areas by anodic dissolving in aqueous NaCl + NaOH elec-trolyte and the nature of inhibitive compounds as Fe(OH)2, Fe(OH)3, Cu(OH)2 are determined. It is proofed the formation of ferrites like CuFe2O4 begin in the anodic space of electrolyser. It has been shown that in aqueous solutions the velocity of brass dissolving is less than of its separate components. The velocity is determined by copper contribution of alloy and depends on CuCl2 concentration in solution. Brass dissolving in water-acetonitrile mixtures is limited by cathode stage of the process. The non-aqueous component compositions areas, in which the mainly processes are zinc dissolving and regular alloy dissolving, are established. The nature of passivating compounds for aqueous CuCl, CuOH and Zn solutions and for water-organic ones of these componds and also of Cu(OH)2 and Zn(OH)2 is determined.Application area: electrochemical dimensional copper and its alloys treatment. Product Description popup.authors popup.nrat_date 2020-04-02 Close