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The organization of teaching electrochemistry for students of various specialities and levels of education (graduate, masters, and postgraduate) at the Belarusian State Technological University (BSTU) is considered. The features of teaching electrochemistry for electrochemists, students of chemico-technological and non-chemical specialities studying at BSTU, are discussed. The benefits of electrochemistry studying for non-electrochemists (both chemico-technological and non-chemical specialities) are presented. The elements of the curriculum for teaching electrochemistry for electrochemists of technological profile are depicted. The examples of enterprises and scientific organizations of Belarus for which electrochemists-technologists work after graduation are shown. The importance of scientific activity of teachers taking electrochemistry and related disciplines for effectiveness of education process is noted. The textbooks usually used at electrochemistry teaching on different education levels are mentioned. This article discusses the challenges encountered in organizing electrochemistry education at BSTU and proposes potential solutions. Graphical abstract

The possibility to adjust the properties of metals, particularly steel, by a combination of elements and material treatments, enables the metal-based civilization as we know it and we live in. The heat treatment of steel can be used to change the microstructure and these microstructure changes affect the properties of the material. A very common heat treatment is the hardening, which is done by a combination of austenitizing, the heating of the steel up to temperatures at which austenitic crystal structure is achieved, followed by quenching, the cooling of the material with high temperatures gradients. Hardening of martensitic stainless steel enables the use of iron-carbon-chromium alloys as tool steels for the processing of various materials. This process is long known and the effects of the hardening procedure on the microstructure are well investigated. The hardening of martensitic stainless steel leads to the formation of a martensitic crystal structure. Martensite has a body centered tetragonal structure with several carbon atoms embedded in the lattice, which increases the hardness. Additional to the phase transformation, the carbides (namely iron and chromium carbides) can dissolve depending on the austenitizing temperature. Although the mechanical properties changes resulting from this process are well understood, the impact on the longevity and durability of the materials is a matter of debate. Several publications regarding this process came to contrary results and predicted increased corrosion resistance as well as decreased corrosion resistance resulting from the hardening process. These contradictions are due to different measurements and due to the fact that the impact of the microstructure on the corrosion behavior and the passivity are not fully understood. By a combination of comprehensive electrochemical measurements and kinetic modeling of passive film growth, this contradiction is solved in this thesis. It is shown that it is necessary to distinguish between the material dissolution in the passivated state, the breakdown of the passive film, which leads to active dissolution, and the dissolution in the active state. These different mechanisms of corrosion can be affected in different ways by the microstructure changes. While the electrochemical measurements are used to compare the behavior of the material during the different stages of corrosion, the modeling is used to reveal the physical causes that lead to the differing behavior. In the following part of the thesis, the heat treatment process is used at another alloy. The investigated, low alloyed, bearing steel shows different microstructure changes due to the same heat treatment. These different changes, especially the differing martensite/austenite phase ratio, affects the electrochemical properties in another way. A higher martensite content accelerates the passive film formation and the film dissolution. The film breakdown, and thus the transition to the active dissolution is also affected by the martensite content. Furthermore, both, film dissolution and film breakdown, are also affected by the carbide dissolution. To isolate the effect of the martensite content on the passive film growth, an additional sample set, consisting of three samples, which differs only in martensite content, is produced by rotary swaging. The modeling of passive film kinetics could confirm the observations done at the bearing steel. The faster formation of passive film at the metal/film interface as well as the faster dissolution of the film at the film/solution interface lead to faster material loss, in the active state as well as in the passivated state. In addition to the material scientific investigations during the work on this thesis, the kinetic modeling of passive film growth is developed as a tool in material science. The modeling of the passive film growth is based on the Point Defect Model, which is used during these investigations, was first presented by the working group of Digby Macdonald in the early 1980s and is further developed since then. The present work is the first case the model was used, to compare the kinetic parameters of different materials and thus to evaluate the influence of microstructure on the passive film kinetics. For this reason, this thesis can also be used as a guide for the work with the Point Defect Model in material science. Therefore, the theoretical background of passive film kinetics, the Point Defect Model, the derivation of the impedance model resulting from the Point Defect Model and the reduction of the model to make it suitable for the fitting is given. Furthermore, a sensitivity analysis regarding the different kinetic parameters is presented for a better understanding of the impact of single parameters on the passive film kinetics and the impedance behavior.