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Information × Registration Number 0225U002271, (0122U000952) , R & D reports Title Development of a scientific basis for the creation of multifunctional oxide ceramic materials and coatings popup.stage_title Створення регламентованих мікроструктур керамічних матеріалів і покриттів на основі оксиду цирконію Head Duriahina Zoia А., Доктор технічних наук Registration Date 27-02-2025 Organization Lviv Polytechnic National University popup.description1 Development of a scientific basis for the creation of multifunctional oxide ceramic materials and coatings that would provide the necessary operating life of critical products made from them. popup.description2 The effect of chemical, phase composition, and sintering temperature on the parameters of the crystal lattice of phases, the morphology of the microstructure, and the mechanical properties of the ZrO2–(3-8) mol.%Y2O3 ceramics was evaluated. The effectiveness of the Vickers indentation method for evaluating the crack resistance characteristics of zirconia ceramics was analyzed. Depending on its percentage content, optimal sintering temperatures have been established for zirconia ceramics doped with yttria. A micromechanism of high-energy fracture of the studied ceramics has been established, which is based on the optimization of the microstructure and phase composition, which ensures high strength and fracture toughness of ceramics. An atlas of microstructures of ZrO2-Y2O3 ceramics has been created. To reduce the cost of Y2O3-doped zirconia ceramics, the possibility of replacing or combining modifiers of different types (MgO, Al2O3, CoO, CeO2, Fe2O3) was studied. In particular, it was found that the complete replacement of yttria with magnesium oxide negatively affected the mechanical properties and fracture toughness. Therefore, the possibility of using complex modification with aluminum, cobalt, cerium, and iron oxides while maintaining a small content of yttria was considered. It has been shown that complexly modified zirconia ceramics sintered at 1580 °C are characterized by increased strength and fracture toughness compared to other modified ceramics. The microhardness, strength, and fracture toughness of zirconia ceramics modified with Y2O3, Al2O3, CeO2, TiO2, MgO, HfO2, and SiO2 were modeled using ensemble machine learning methods. It was found that the boosting class methods showed the highest accuracy in predicting each of the three mechanical properties. Matrix models of the distribution of internal free space in ZrO2–Y2O3, ZrO2–MgO, ZrO2–Y2O3–Al2O3–CoO–CeO2–Fe2O3 ceramics have been developed using the positron annihilation method. Product Description popup.authors Bohun Lidiia I. Vavrukh Valentyna I. Vasyliv Bohdan D. Klym Halyna I. Kovbasiuk Taras M. Krechkovska Sofiia R. Kulyk Volodymyr V. Lemishka Ihor A. Liutyi Pavlo Ya. Tepla Tetiana L. Trostianchyn Andrii M. Shevchuk Vira H. popup.nrat_date 2025-02-27 Close