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Information × Registration Number 0223U000768, 0120U102128 , R & D reports Title Structure, Kinetics of Forming and Physicochemical Properties of Aluminum Based Nanophase Composites popup.stage_title Head Boichyshyn Lidia M., Кандидат хімічних наук Registration Date 19-01-2023 Organization Ivan Franko National University of Lviv popup.description2  Using the X-ray diffraction method, it was established that the original (amorphous) samples of AMC of the Al‒PZM‒Ni/Fe system (PZM  Y, Gd and Dy) have a characteristic cluster structure. The first coordination sphere is characterized by a high value of the coordination number (12) and a large proportion of the free volume. Aluminum atoms mainly take part in its formation, but in addition to Al‒Al bonds, RZM‒Al and (Ni, Fe)‒Al bonds are also formed. Based on the results of the DSC research, the kinetic parameters of nanocrystallization were determined, including the value of the coefficient that is proportional to the number of crystallization nuclei, and the nanocrystallization rate constant k. AMCs with Fe additions have the highest thermal stability, which confirms the lowest values of the constants. The results of studies of specific electrical resistance by the four-probe method showed that in the temperature range from 300 K to the temperature of the maximum of the first stage of crystallization, Al-AMC behaves not as classical conductors of the first kind, but rather as semiconductors. It was found that the Al87Y5Ni8, Al87Gd5Ni8 and Al87Gd5Ni4Fe4 alloys have the highest values of microhardness among the initial samples of AMC of the Al‒PZM‒Ni/Fe system (PZM  Y, Gd and Dy). After one-hour annealing of the samples at the temperature of the maximum of the first stage of nanocrystallization Tx1, the microhardness of all samples reaches its maximum value, increasing by 50‒800% depending on the composition of the AMC, which is explained by the formation of nanocrystals and the formation of elastic boundaries of dislocations enriched in RZM and PM. Product Description popup.authors Hertsyk Oksana Myronivna Kovbuz Myroslava O. Kulyk Yuri O. Lopachak Mariya Mykolaivna Khrushchyk Khrystyna Ivanivna popup.nrat_date 2023-01-19 Close