Work number - M 18 AWARDED
Presented KARPENKO PHYSICO-MECHANICAL INSTITUTE OF THE NAS OF UKRAINE
Kukhar I.S., Stypnutskyy T.R., Lavrys’ S.M.
In the scientific works new methods and approaches to the engineering of the surface of structural materials are proposed to extend their life, expand the scope of use by increasing the exploitation properties (wear and corrosion, corrosion-abrasion resistance) by forming multifunctional coatings.
New powder wires were developed which based on the Fe–Cr–C and
Fe–Cr–B systems for the formation of wear-resistant electric arc coatings with 1.8 times higher abrasion resistance and increased corrosion resistance in neutral aqueous media. Formation of such coatings can be an alternative to environmentally hazardous Galvanic plating. A new approach to the intensification of nitriding of two-phase titanium alloys of different structural state is developed, which consists in preliminary grinding of the surface layer structure and forming the balance of the surface hardening/surface quality ratio by cold surface plastic deformation. It is shown that the implementation of this approach is most effective for alloys with plate structure. The parameters of deformation-diffusion treatment, which provide the formation of nitride coatings, halve the intensity of wear and reduce the coefficient of friction from 0.2 to 0.1 in tribobars with bronze and increase corrosion resistance in particularly aggressive environments. For the first time confirmed the universality and set temperature and deformation conditions for realization of the effect of liquid metal embrittlement of ferritic, ferrite-martensitic and austenitic steel in liquid lead: liquid metal embrittlement is implemented in the temperature range 350...450 °C, and deformations 0.8...1.0% for pure cyclic bending, causing a decrease in the life of the material. To improve the corrosion-mechanical properties of steels it is proposed to form oxide coatings on their surfaces. Recommended oxidation modes that provide continuous formation of oxide coating enriched with chromium, for the preservation of mechanical properties of structural materials. New approaches developed by the authors to the surface engineering of steels and titanium alloys will allow the formation of multifunctional coatings, ensuring the reliability and durability of structures in products of aviation, mechanical engineering, power engineering and other industries.
The results obtained correspond to the current level of world achievements in the field of materials science, which is confirmed by publications in the leading scientific journals of Ukraine and abroad.
Number of publications: 24 articles in professional publications, which are referenced in SCOPUS (including some of them included in Q1 - Tribolodgy International, Surface and Coating Technology, Journal of Thermal Spray Technology, Biotribology), as well as 1 monograph and 2 patents of Ukraine for the invention.