The works devoted to the electrodeposition of metals, alloys, and semiconductors onto the substrates through the templates of various non-conducting materials with pores of various shapes and sizes...

The problems of overcoming titanium passivity that hampers reaching high rates of its anodic dissolution, the optimization of electrolyte composition, and the mode of electrochemical machining (ECM) are considered. The anodic potentials of machining and the current efficiencies for titanium ionization reaction in relation to the anionic composition of electrolyte and the nature of solvent are presented. Some details of the mechanism of high-rate anodic dissolution of metal, which determine the main results of ECM, are considered. The examples of techniques of ECM of titanium and their biomedical and aircraft industry applications are presented.

The review is devoted to the modern methods of local maskless electrochemical machining of metals and semiconductors with the aim of formation of individual islands or cavities, their groups, and patterns according to a given program on their surface, or 3D micro/nanostructures, for example, metal threads and various thread structures. For this purpose, various methods of localizing the electrochemical deposition, dissolution, or oxidation are used.

Based on the measured voltammograms, the corrosion potentials and corrosion current densities of Mo, Re, and several their alloys in the NaCl solutions were determined by the method of Tafel extrapolation. The dependences of E _corr and i _corr on the alloy composition, including the corresponding values for the metals (alloy components), were plotted. The obtained values of i _corr and the corrosion rates in the linear units were compared with the literature data.

Pitting corrosion of stainless steel 403 in the NaCl solutions is studied. It is shown that the experimental results obtained under the potentiostatic conditions do not provide sufficient information on the behavior of steel under the conditions of free corrosion. The corrosion experiments take long time, their results exhibit poor reproducibility; however, they are necessary for obtaining reliable data on the corrosion behavior of steel. The development of corrosion process is reflected in the variation of corrosion potential with time. The effect of concentration and temperature of NaCl solutions on the development of pitting corrosion is studied. The peculiarities of the distribution of pits over the test specimen surface are revealed. In 1 M NaCl solution at 20°C, few pits arise. Some of them repassivate; some pits grow, initially, in diameter and depth and, then, almost only in depth. The examples of through pit formation on the specimens 4 mm thick are presented.

A method for estimating pitting corrosion rate is proposed. The method is based on the analysis of anodic and cathodic voltammograms that were measured on the specimens of two types: on the test specimen coated with an oxide film, which formed under the open-circuit conditions, and on the specimen, whose surface was totally activated with aggressive ions. The use of Tafel portions of these voltammograms in various combinations enables us to estimate the corrosion potential and corrosion current for general corrosion proceeding in the induction period, for pitting corrosion at the initial stage of its development, for a highly developed pitting corrosion, when the major area of specimen surface is occupied with pits, and also in the intermediate case.