Pokhmurs'ka G. Development of structure inhomogeneity in metals under laser processing and its influence on the main exploitation properties

Surface layers on steels, aluminium and magnesium alloys that are formed under laser treatment. Establishing of principles of heterogeneity formation, which occurs on the in surface layers of materials and materials with coatings during laser treatment with the aim to achieve deeper scientific understanding of processes and development of optimal schemes of surface modification of materials to improve their durability, wear and corrosion resistance. Electron microscope and X-Ray analysis, methods of investigations of mechanical, tribological and corrosion properties, mathematical modeling. The influence of the secondary heterogeneity, which is formed under the action of localized sources of energy that is used for heating of steel and alloy surfaces, on the strength under different load conditions, characteristics and mechanisms of wear under different load, electrochemical and corrosion properties. A mathematical model of crack formation in thermal spray coatings after laser melting is developed. Mechanisms of laser reinforcement of light alloys with hard particles are investigated. New approaches in laser processing schemes that consider the exploitation conditions are proposed. Method of laser modification of thermal spray coating is implemented with economical effect 320 thousands UAH. Recommendations suggesting laser processing of aluminium alloys are considered in practice and are perspective for more wide implementation in another branches of industry.