Mechnik V. А., Bondarenko N. А., Kolodnitsky V. M., Zakiev V. I., Zakiev I. M., Gevorkyan E. S., Kuzin N. O., Yakushenko O. S., Semak I. V. Comparative Study of the Mechanical and Tribological Characteristics of Fe–Cu–Ni–Sn Composites with Different CrB2 Content under Dry and Wet Friction. Journal of Superhard Materials. 2021. Vol. 43, Iss. 1. P. 52–64. DOI: 10.3103/S1063457621010044. Full text is absence. Comparative Study of the Mechanical and Tribological Characteristics of Fe– Cu–Ni–Sn Composites with Different CrB2 Content under Dry and Wet Friction Mechnik, V. A. Bakul Institute for Superhard Materials, National Academy of Sciences of Ukraine, Kyiv, Ukraine Bondarenko, N. A. Bakul Institute for Superhard Materials, National Academy of Sciences of Ukraine, Kyiv, Ukraine Kolodnitskyi, V. M. Bakul Institute for Superhard Materials, National Academy of Sciences of Ukraine, Kyiv, Ukraine Zakiev, V. I. National Aviation University, Kyiv, Ukraine Zakiev, I. M. National Aviation University, Kyiv, Ukraine Gevorkyan E. S., Ukrainian State Academy of Railway Transport, Kharkiv, Ukraine Kuzin N. O., Lviv branch, Dnipro National University of Railway Transport, Lviv, Ukraine Yakushenko O. S., National Aviation University, Kyiv, Ukraine Semak I. V. National Aviation University, Kyiv, Ukraine Abstract. The structure, phase composition, hardness, and elasticity modulus of sintered Fe–Cu–Ni–Sn–CrB2 composites and their tribological properties under dry and wet friction have been studied by X-ray diffraction, scanning electron microscopy, microindentation, and tribological testing. The obtained results have demonstrated that the microstructure and mechanical and tribological properties of these composites depend on the CrB2 additive content. The Fe–Cu–Ni– Sn–CrB2 composites incorporate the α-Fe, γ-Fe, and Cu phases and a certain fraction of the crystalline Cu9NiSn3, NiSn3, and CrB2 phases. The hardness and elasticity modulus of these composites are almost independent of the friction medium (dry or wet), and the friction force and