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Information × Registration Number 0221U102479, 0118U003063 , R & D reports Title The role of interfaces in strengthening new super-hard nanocomposite coatings: experiment and theory popup.stage_title Head Ivaschenko Volodimir Ivanovich, Доктор фізико-математичних наук Registration Date 03-02-2021 Organization Institute of Problems of Materials Science named after IM Frantsevich of the National Academy of Sciences of Ukraine popup.description2 The object of investigations is the structure of interfaces and their stability in nanocomposites based on transition metal compounds; properties of nanocomposite and nanolayer coatings and coating material. The aim of the work is to establish the structure and stability of interfaces in heterostructures based on transition metal compounds and their role in the formation of the properties of nanocomposite coatings Ti-Al-Si-C and Ti-B-C. First-principles calculations of heterostructures TiX(001)/SiY, TiX (111)/SiY (X, Y = C, N), and TiB2(001)/(C, BC, BN, AlN, SiC) showed that nonmetallic interfaces in TiX (001)/SiY will be amorphous even at high temperatures (up to 1400 K), except for the TiN(001)/SiC interface that undergoes B1-B3 transformation at 700 K. All interfaces in TiX (111)/SiY were dynamically stable, however, the TiC (111)/ SiN and TiN(111)/SiC interfaces transform to B3-like layers due to mechanical instability. Interfaces in TiB2-based heterostructures are amorphous, except for the AlN layer that undergoes the B1-B4 transformation during relaxation. Magnetron coatings were obtained by sputtering the Ti+Al, C, TiB2, B4C targets depending on the discharge power on graphite and non-metallic targets. After annealing in the deposited amorphous Ti-Al-C Ti-Al-Si-C coatings the MAX phases, their solid solutions and amorphous interfaces were detected. Ti-B-C coatings represent TiB2-xCx phases surrounded by an amorphous B-C-O matrix. The hardness reached 54 GPa for grain size of 10 nm. Nanolayer coatings TiB2/C, TiB2/B4C showed a hardness of about 40 GPa and it depended on the thickness of the amorphous layers. The results of theoretical and experimental studies show that in nanocomposites can form heteroepitaxial layers under certain conditions (compositions and temperatures) that promote their strengthening. Also, there are critical thicknesses of amorphous layers, and nanocomposite coatings with such layers will have maximum hardness. Product Description popup.authors Ivashchenko Liudmyla A Bykov Oleksandr I Vasylkivska Maryna A Granko Vasyl Kovalchenko Andriy M Kozak Andriy O Korichev Sergiy F Marchuk Oleksandr K Medyuh Nazar R Olifan Olena I Onopriyenko Oleksiy O Osadcha Ala V Porada Oleksandr K Sinelnychenko Oleksiy K Sytikov Oleksandr O Skrynsky Petro L Tymofeyeva Izabela I Shevchenko Volodymyr I popup.nrat_date 2021-02-03 Close