Browsing by Author "Dub, S. N."

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Physico-Mechanical and Tribological Properties of Fe–Cu–Ni–Sn and Fe–Cu–Ni–Sn–VN Nanocomposites Obtained by Powder Metallurgy Methods
    (Faculty of Engineering, University of Kragujevac, Serbia, 2019) Mechnik, V. A.; Bondarenko, N. A.; Kolodnitskyi, V. M.; Zakiev, V. I.; Zakiev, I. M.; Dub, S. N.; Storchak, M.; Kuzin, Nickolai O.
    EN: Abstract. The results of studies aimed at improving the mechanical and operational properties of the Fe–Cu–Ni–Sn and Fe–Cu–Ni–Sn–VN composite materials obtained by powder metallurgy methods are presented. A comparative analysis of mechanical and tribological characteristics, including the determination of nanohardness, elastic modulus, friction force, friction coefficient, and volume of wear groove was performed. It was shown that the use of 3 wt% nano-dispersed VN powder in the 51Fe–32Cu–9Ni–8Sn charge, in which the grain size was ~2000–5000 nm, makes it possible to increase the nanohardness from 2.68 to 5.37 GPa and reduce the elastic modulus from 199 to 125 GPa. As a result, the parameters H/E and H3/E2, which describe the resistance of the material to the elastic deformation of failure and the resistance of the material to plastic deformation, increase by 3.3 and 20 times, respectively, and the friction force and the volume of the wear groove decrease by 1.8 and 16 times, respectively. The reasons for the change in the mechanical characteristics of sintered composites during nanoindentation and the different nature of their wear are discussed. The interrelation of the microstructure with mechanical and tribological properties is established. It is shown that the parameters H/E and H3/E2 can be used to predict the wear resistance of the composites under study.
  • No Thumbnail Available
    Item
    A Study of Microstructure of Fe-Cu-Ni-Sn and Fe-Cu-Ni-Sn-Vn Metal Matrix for Diamond Containing Composites
    (Published by Elsevier Inc., 2018) Mechnik, V. A.; Bondarenko, N. A.; Dub, S. N.; Kolodnitskyi, V. M.; Nesterenko, Yu. V.; Kuzin, Nickolai O.; Zakiev, I. M.; Gevorkyan, E. S.
    EN: To obtain bulk of 51Fe–32Cu–9Ni–8Sn and 49.47Fe–31.04Cu–8.73Ni–7.76Sn–3VN nanocomposites, a pressing method at room temperature and subsequent hot pressing in a vacuum was used. The microstructure of the sintered composites by X-ray diffraction and transmission electron microscopy was investigated. It is shown that in the 49.47Fe–31.04Cu–8.73Ni–7.76Sn–3VN composite there was a dissolution of vanadium nitride in γ‑iron and formation of a supersaturated solid solution of nitrogen and vanadium in the α‑iron. As a result, there was a substantial grinding of ferrite grains (from 5 to 50 μm to 20–400 nm) as compared to a sample without vanadium nitride (from 5 to 50 μm to 400–800 nm). Nanocomposites are considered as promising materials to create a new generation of diamond containing composites.