Institute for Problems of Chemical and Energetic Technologies of the Siberian Branch оf the Russian Academy of Sciences, Biysk, Russia¹ ; National Research Tomsk State University, Tomsk, Russia²

E. S. Marchenko, Leading Researcher¹, Head of the Laboratory for Medical Alloys and Shape Memory Implants², Doctor of Physical and Mathematical Sciences, e-mail: 89138641814@mail.ru

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

M. A. Kovaleva, Postgraduate Student, Research Engineer
T. V. Chaikovskaya, Professor, Doctor of Physical and Mathematical Sciences

The results of a synchrotron study of the phase composition and cyclic stability of a thin wire and a metal mesh made of a NiTi alloy filament are presented. Fatigue tests of NiTi alloy wire in air and in aggressive media have shown high fatigue resistance. More than 1 million load-unloading cycles related to stress relaxation due to superelasticity have been performed. When the knitwear is deformed by stretching, the effect of superelasticity is suppressed, and the deformation diagram demonstrates nonlinear hyperelastic behavior. This is due to the formation of a complex stress state with inhomogeneous fields of deformations and stresses in the loop material during stretching, which is confirmed by the results of numerical modeling. An analysis of the results of numerical modeling of the representative cell stretching of the studied metal mesh showed the formation of a complex stress state with inhomogeneous zones of deformations and stresses in the loop material. It is established that during uniaxial metal mesh stretching, stress concentrators appear on the contact pads in areas of greatest curvature, and maximum stress values occur in localized zones. Cyclic loading of a metal mesh in air and in a 1% HCl solution showed that the samples of the mesh passed 1.5 million cycles in air without destruction, which is significantly higher than that of NiTi alloy wire. When cycling NiTi alloy wire in a 1% HCl solution, starting from 104 cycles, there is a decrease in the values of the martensite shear stress during forward and reverse martensitic transformations. In cyclic tests in 1% HCl solution, thin wire samples showed less ability to resist fatigue in contrast to air tested samples.
The research was carried out within the framework of the state assignment of the Ministry of Science and Higher Education of the Russian Federation under the project No. FVR-2020-0022.
The research was performed using the equipment of the Tomsk Regional Common Use Center of the Tomsk State University with the support of a grant from the Ministry of Science and Higher Education of the Russian Federation 075-15-2021-693 (No. 13.RFC.21.0012).

1. Zhu J., Zeng Q., Fu T. An updated review on TiNi alloy for biomedical applications. Corros. Rev. 2019. Vol. 37, Iss. 6. pp. 539–552.
2. Zhang L., Zhang Y. Q., Jiang Y. H., Zhou R. Superelastic behaviors of biomedical porous NiTi alloy with high porosity and large pore size prepared by spark plasma sintering. J. Alloy Compd. 2015. Vol. 644. pp. 513–522.
3. Heller L., Seiner H., Sittner P., Sedlаk P. et al. On the plastic deformation accompanying cyclic martensitic transformation in thermomechanically loaded NiTi. Int. J. Plast. 2018. Vol. 111. pp. 53–71.
4. de Vasconcellos L. M. R., Rodarte Y., do Prado R. F., de Vasconcellos L. G. O. et al. Porous titanium by powder metallurgy for biomedical application: characterization, cell citotoxity and in vivo tests of osseointegration. Biomed. Eng. 2012. Vol. 1. pp. 47–74.

5. Es-Souni M., Es-Souni M., Fischer-Brandies H. Assessing the biocompatibility of NiTi shape memory alloys used for medical applications. Anal. Bioanal. Chem. 2005. Vol. 381. pp. 557–567.
6. Li C. Y., Yang X. J., Zhang L. Y., Chen M. F. et al. In vivo histological evaluation of bioactive NiTi alloy after 2 years implantation. Mater. Sci. Eng. 2007. Vol. 27. pp. 122–126.
7. Muhamedov M., Kulbakin D., Gunther V., Choynzonov E. et al. Sparing surgery with the use of TiNi-based endografts in larynx cancer patients. J. Surg. Oncol. 2015. Vol. 111. pp. 231–236.
8. Shtin V., Novikov V., Chekalkin T., Gunther V. et al. Repair of orbital post-traumatic wall defects by custom-made TiNi mesh endografts. J. Funct. Biomater. 2019. Vol. 10. pp. 1–9.
9. Topol`nickij E., Chekalkin T., Marchenko E., Yasenchuk Yu. et al. Evaluation of clinical performance of TiNi-based implants used in chest wall repair after resection for malignant tumors. J. Funct. Biomater. 2021. Vol. 12. 60.
10. Marchenko E., Baigonakova G., Yasenchuk Yu., Chekalkin T. Structure, biocompatibility and corrosion resistance of the ceramic-metal surface of porous nitinol. Ceram. Int. 2022. Vol. 48, Iss. 22. pp. 33514–33523.
11. Bansiddhi A., Sargeant T., Stupp S., Dunand D. Porous NiTi for bone implants: A review. Acta. Biomater. 2008. Vol. 4. pp. 773–782.
12. Sakamoto Y., Hirano K., Iida O., Soga Y. et al. Five-year outcomes of self-expanding nitinol stent implantation for chronic total occlusion of the superficial femoral and proximal popliteal artery. Catheter. Cardiovasc. Interv. 2013. Vol. 82. pp. 251–256.
13. Song C. History and current situation of shape memory alloys devices for minimally invasive surgery. Open. Med. Dev. J. 2010. Vol. 2. pp. 24–31.
14. Jenko M., Godec M., Kocijan A., Rudolf R. et al. A new route to biocompatible Nitinol based on a rapid treatment with H2/O2 gaseous plasma. Appl. Surf. Sci. 2019. Vol. 473. pp. 976–984.
15. Yasenchuk Yu., Marchenko E., Gunther S., Baigonakova G. et al. Softening effect during cyclic stretching of titanium nickelide knitwear. Mater. 2021. Vol. 27. pp. 459–481.
16. Chen Y., Tyc O., Molnarova O., Heller L. et al. Tensile deformation of superelastic NiTi wires in wide temperature and microstructure ranges. Shap. Mem. Superelasticity. 2019. Vol. 5. pp. 42–62.
17. Marandi L., Sen I. In-vitro mechanical behavior and high cycle fatigue characteristics of NiTi-based shape memory alloy wire. Int. J. Fatigue. 2021. Vol. 148. 106226.
18. Zhu X., Zhang X., Qian M. Reversible elastocaloric effects with small hysteresis in nanocrystalline Ni – Ti microwires. AIP Adv. 2018. Vol. 8. 125002.
19. Mahtabi M., Shamsaei N., Mitchell M. Fatigue of Nitinol: The state-ofthe-art and ongoing challenges. J. Mech. Behav. Biomed. Mater. 2015. Vol. 50. pp. 228–254.
20. Ammar O., Haddar N., Dieng L. Experimental investigation of the pseudoelastic behaviour of NiTi wires under strain- and stress-controlled cyclic tensile loadings. Intermet. 2017. Vol. 81. pp. 52–61.
21. Morch A., Astruc L., Witz J., Lesaffre F. et al. Modeling of anisotropic hyperelastic heterogeneous knitted fabric reinforced composites. J. Mech. Phys. Solids. 2019. Vol. 27. pp. 47–61.
22. Baigonakova G., Marchenko E., Chekalkin T., Kang J. et al. Influence of silver addition on structure, martensite transformations and mechanical properties of TiNiAg alloy wires for biomedical application. Mater. 2020. Vol. 13. pp. 1–11.
23. Li S., Mao Ch., Li H., Zhao Ya. Mechanical properties and theoretical modeling of self-centering shape memory alloy pseudo-rubber. S. Mater. Struct. 2011. Vol. 20. 115008.
24. Qin Y. Applications of advanced technologies in the development of functional medical textile materials. Med. Tex. Mater. 2016. pp. 55–70.
25. Robertson S., Pelton A., Ritchie R. Mechanical fatigue and fracture of Nitinol. Int. Mater. Rev. 2012. Vol. 57. pp. 1–37.
26. Svetogorov R., Dorovatovskii P., Lazarenko V. Belok/XSA diffraction beamline for studying crystalline samples at Kurchatov Synchrotron Radiation Source. Cryst. Res. Technol. 2020. Vol. 55, Iss. 5. 1900184.
27. Hubbard C., Evans E., Smith D. The reference intensity ratio, I/Ic, for computer simulated powder patterns. J. Appl. Cryst. 1976. Vol. 9. pp. 169–174.
28. Robles R. R., Gómez D. L., Nieto F. A. Cooperative formation flying control laws for automatic air to air refuelling. EUCASS. 2019. 8. DOI: 10.13140/RG.2.2.32098.58560
29. Ravandi M., Moradi A., Ahlquist S., Banu M. Numerical simulation of the mechanical behavior of a weft-knitted carbon fiber composite under tensile loading. Polym. 2022. Vol. 14. 451.
30. Otsuka K., Ren X. Physical metallurgy of Ti – Ni-based shape memory alloys. Prog. Mater. Sci. 2005. Vol. 50. pp. 511–678.