Zn-Ni coatings were deposited under galvanostatic conditions on steel substrate (OH18N9). The influence of current density of deposition on the surface morphology, chemical and phase composition was investigated. The corrosion resistance of Zn-Ni coatings obtained at current density 10–25 mA cm−2 are measured, and are compared with that of metallic cadmium coating. Structural investigations were performed by the X-ray diffraction (XRD) method. The surface morphology and chemical composition of deposited coatings were studied using a scanning electron microscope (JEOL JSM-6480) with EDS attachment. Studies of electrochemical corrosion resistance were carried out in the 5% NaCl, using potentiodynamic and electrochemical impedance spectroscopy (EIS) methods. On the ground of these research, the possibility of deposition of Zn-Ni coatings contained 24–26% at. Ni was exhibited. It was stated, that surface morphology, chemical and phase composition of these coatings are practically independent on current density of deposition. On the basis of electrochemical investigations it was found that corrosion resistance of these Zn-Ni coatings is also independent of current density. These coatings are more corrosion resistant in 5% NaCl solution than metallic cadmium. It was suggested that the Zn-Ni coating may be used as a substitute for toxic cadmium.
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机译:Zn-Ni涂层在恒电流条件下沉积在钢基材(OH18N9)上。研究了沉积电流密度对表面形貌,化学和相组成的影响。测量了在电流密度10–25 mA cm -2 sup>下获得的Zn-Ni涂层的耐腐蚀性,并将其与金属镉涂层的耐蚀性进行了比较。结构研究是通过X射线衍射(XRD)方法进行的。使用附有EDS的扫描电子显微镜(JEOL JSM-6480)研究了沉积涂层的表面形态和化学成分。使用电位动力学和电化学阻抗谱(EIS)方法在5%NaCl中进行了耐电化学腐蚀的研究。基于这些研究,Zn-Ni涂层沉积的可能性为24–26%at。镍被展出。据指出,这些涂层的表面形态,化学和相组成实际上与沉积电流密度无关。根据电化学研究,发现这些Zn-Ni涂层的耐腐蚀性也与电流密度无关。这些涂层在5%NaCl溶液中比金属镉更耐腐蚀。有人建议锌锌镍涂层可以代替有毒镉。
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