ADVANCED CHARACTERIZATION METHODS FOR NICKEL AND ZINC-NICKEL ALLOY LAYERS ELECTROCHEMICALLY DEPOSITED

Abstract

Nickel and zinc-nickel alloys were electrochemically deposited. The layers were studied with scanning electron microscope (SEM), composition was revealed through studies of energy dispersive of X-rays (EDX) and X-ray diffraction (XRD), the reflectance was studied by reflectance spectroscopy and the hardness with a Vickers indenter device. Nickel electroplating has a great commercial and industrial importance and offers a very good quality finish of surfaces. This importance is emphasized by increasing of annual global consumption of nickel, which goes to 100.000 tones. The applications of electroplating could be derived in three categories: decorative, functional and electroforming. In ordinary coating the zinc remains the principal metal for industrial applications, especially for coverage of steel products. In the last two decades it was registered an important increasing of application of electrodeposited alloys due to the market demand for products with high quality coatings. On the first place there are the machine buildings industry and the aerospace industry, also those for electrical components and for fixing devices. Because of fact that consumption of heavy metals has to be reduced year by year, until the total elimination, there are searching for new technologies and one of the most promised of them is that of alloys electrochemical coatings with Zn-Ni, Zn-Co and Zn-Fe.