Institute for Problems of Chemical and Energetic Technologies SB RAS, Biysk, Russia ; National Research Tomsk State University, Tomsk, Russia

E. S. Marchenko, Associate Professor, Leading Researcher¹, Head of the Laboratory of Medical Alloys and Shape Memory Implants², Doctor of Physical and Mathematical Sciences

National Research Tomsk State University, Tomsk, Russia
G. A. Baygonakova, Senior Researcher, Candidate of Physical and Mathematical Sciences

V. A. Larikov, Postgraduate Student, Junior Researcher, e-mail: calibra1995se@gmail.com
E. D. Khabibova, Junior Researcher

The structure, phase composition and corrosion resistance of the porous TiNi alloy with the addition of 0.5% (at.) silver nanoparticles obtained by the self-propagating high-temperature synthesis method were studied. X-ray diffraction analysis showed the presence of TiNi (B2), Ti₄Ni₂O, TiAg and CaTiO₃ phases. The predominance of the TiNi (B2) phase indicates the preservation of the titanium nickelide structure, and the presence of the Ti₄Ni₂O and TiAg phases indicates the formation of intermetallic compounds and oxides during the synthesis. The CaTiO₃ phase is probably formed as a result of calcium impurities in the titanium powder. The results of scanning electron microscopy and element mapping showed that silver is localized mainly at the boundaries of Ti₄Ni₂O inclusions, interacting with calcium and titanium. This may indicate a significant effect of silver on the change in the micro- and nanostructure of the alloy. Electrochemical impedance spectroscopy and potentiodynamic measurements revealed a significant effect of silver addition on the corrosion properties of the alloy. There is a decrease in polarization resistance and an increase in the corrosion current density for the TiNi – 0.5 Ag alloy compared to pure TiNi, which indicates a decrease in the corrosion resistance of the alloy with the addition of silver. A shift in the corrosion potential to a more positive side and a change in the phase composition of the oxide layer were also recorded, which is explained by the formation of the CaTiO₃ phase. Thus, the addition of 0.5% (at.) silver nanoparticles to the porous TiNi alloy improves the conductivity of the material, but reduces its corrosion resistance.
The research was carried out under support of the RF Ministry of Science and Higher Education according to the project No. FSWM-2025-0009.

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