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Information × Registration Number 0211U000938, 0108U005836 , R & D reports Title Development of physico-chemical fundamentals of oxynitriding technology to improve the wear and the corrosion-resistance of titanium alloys popup.stage_title Head Fedirko Viktor Mykolayovych, Registration Date 09-03-2011 Organization Karpenko Physico-Mechanical Institute of the National Academy of Science of Ukraine popup.description2 It is shown that the effective oxynitriding can be conducted in the temperature range 750-950oC (for exposion 5 h). In this case, at stable gas-dynamic parameters (partial pressure of nitrogen and oxygen) in the surface layer multilayered thermal diffusion coating are formed, consisted oxynitride compound (outer layer), titanium nitride Ti2N and diffusion layer of solid solution of nitrogen and oxygen in titanium. It was established that the optimal scheme of oxynitriding is multicomponent saturation on the cooling stage. In this case the oxygen alloyed of previously formed nonstoichiometric nitride. It was shown that the controlled modification of nitride with oxygen (oxynitriding) is more intensive when nitride contains a larger number of vacancies in the nonmetal sublattice. The effect of oxynitriding (the increase of surface microhardness) is higher when the composition of nitride is closer to the upper boundary of its homogeneity. It was established that the oxynitride coating more effectively protects titanium alloys in the very aggressive media (20% HCl, 40 i 80% H2SO4, 3% NaCl) as compared to the oxide and nitride. The better corrosion protection is provided by coating with a high content of oxynitride phases, as well as high content of nitrogen in the titanium oxynitride. Oxynitriding provides higher level of mechanical properties of titanium alloys (strength, ductility) compared to nitriding and oxydizing. It was shown that the oxynitride coating effectively improve the wear resistance of titanium alloys as compared to oxide and nitride ones. In particular, for the friction pair with bronze oxynitride coating provides a lower friction coefficient than oxide and nitride. Proposed modes of oxynitriding improve the corrosion resistance of titanium alloys in oxygen-containing high concentrated acids and wear resistance of titanium alloys in a pair with steel. Product Description popup.authors Кудлак Степан Михайлович Яськів Олег Ігорович popup.nrat_date 2020-04-02 Close