Study of the mechanical properties of TiNi-based lattice structures produced by selective laser melting

The properties of the initial TiNi powder and lattice specimens fabricated from it by selective laser melting (SLM), were investigated, and the factors affecting their mechanical performance were identified. The particle-size distribution and particle shape characteristics were determined by laser diffraction, while the elemental composition of the initial powder was determined by energy- dispersive X-ray fluorescence spectroscopy. X-ray computed tomography was performed on both the powder sample and the fabricated specimens. The processing characteristics of the powder were evaluated in accordance with the applicable GOST standards. Spiral and sinusoidal lattice specimens were fabricated by SLM. Their stress–strain response was simulated using the finite element method. The specimens were then subjected to compression testing followed by fractographic examination. The powder contained 45.41 wt. % Ti and 54.59 wt. % Ni, and no foreign particles were detected. Particle sizes ranged from 5 to 63 μm, with a median particle size of 33.566 μm. The bulk density, tapped density, and Hall flow rate were 3.92 g/cm³, 4.29 g/cm³, and 17.1 s/50 g, respectively. Sinusoidal and spiral specimens with a diameter of 2 mm, a height of 15 mm, and a strut thickness of 150 μm were produced by SLM. The numerical results showed that the maximum von Mises equivalent stresses in the struts reached the yield strength of the material and was concentrated at the junctions where the struts began to branch. Compression testing yielded stress-strain curves for the specimens in different cross-sections. The stresses in the central regions of the strut junctions were 173.25 ± 8.67 MPa for the sinusoidal structures and 148.75 ± 7.44 MPa for the spiral structures, whereas the stresses in the strut branching regions were 74.93 ± 7.50 MPa and 74.38 ± 7.44 MPa, respectively. Fractographic analysis revealed a mixed fracture mechanism.

1. Chernyshikhin S.V., Pelevin I.A., Karimi F., Shishkovsky I.V. The study on resolution factors of LPBF technology for manufacturing superelastic NiTi endodontic files. Materials. 2022;15(19):6556. https://doi.org/10.3390/ma15196556

2. Varun Krishna V.R., Sahu S.K., Rama Sreekanth P.S., Menon S., Ma Q., Deepthi Y.P. Modeling and finite element simulation of sustainable coronary stent with a variation in unit cell design. International Journal on Interactive Design and Manufacturing (IJIDeM). 2025;19(6): 3947–3956. https://doi.org/10.1007/s12008-024-01944-6

3. Liu D., Zhao Y., Zhang S., Li M., Pang G. Superior mechanical properties of an additively manufactured gra­dient lattice structure through FEM simulation and in-situ compression tests. Materials Today Communications. 2024;42(4): 111115. https://doi.org/10.1016/j.mtcomm.2024.111115

4. Finazzi V., Berti F., Guillory II R.J., Petrini L., Previtali B., Demir A.G. Patient-specific cardiovascular superelastic NiTi stents produced by laser powder bed fusion. Procedia CIRP. 2022;110:242–246. https://doi.org/10.1016/j.procir.2022.06.044

5. Jiang W., Zhao W., Zhou T., Wang L., Qiu T. A review on manufacturing and post-processing technology of vascular stents. Micromachines. 2022;13(1):140. https://doi.org/10.3390/mi13010140

6. Das A., Mehrotra S., Kumar A. Advances in fabrication technologies for the development of next-generation cardiovascular stents. Journal of Functional Biomaterials. 2023;14(11):544. https://doi.org/10.3390/jfb14110544

7. Pan C., Han Y., Lu J. Structural design of vascular stents: A review. Micromachines. 2021;12(7):770. https://doi.org/10.3390/mi12070770

8. Sheydaeian E., Nam R., Gerdt L., Rentsch М., Vetter B., Stepien L., Lopez E., Brückner F., Naguib H., Leyens C. Additive manufacturing of zinc auxetic stents: Tuning mechanical properties through process and structural design. Journal of Manufacturing Processes. 2025;152:442–457. https://doi.org/10.1016/j.jmapro.2025.08.040

9. Dol A., Ivanov D., Fomkina O. Optimizing the process of developing human blood vessel models. Saratov Medical Journal. 2020;1(2):e0201. https://doi.org/10.15275/sarmj.2020.0201

10. Dzogbewu T.C., de Beer D.J. Additive manufacturing of NiTi shape memory alloy and its industrial applications. Heliyon. 2024;10(1):e23369. https://doi.org/10.1016/j.heliyon.2023.e23369

11. Vanaei S., Hashemi M., Solouk A., Ilani M.A., Amili O., Hef­zy M.S., Tang Y., Elahinia M. Manufacturing, processing, and characterization of self-expanding metallic stents: A comprehensive review. Bioengineering. 2024;11(10):983. https://doi.org/10.3390/bioengineering11100983

12. McGee O.M., Geraghty S., Hughes C., Jamshidi P., Kenny D.P., Attallah M.M., Lally C. An investigation into patient-specific 3D printed titanium stents and the use of etching to overcome Selective Laser Melting design constraints. Journal of the Mechanical Behavior of Biomedical Materials. 2022;134(3):105388. https://doi.org/10.1016/j.jmbbm.2022.105388

13. Miličić Lazić M., Mitić D., Dojčinović B., Lazić M., Popović A.S., Grgur B.N. Determination of the corrosion and biocompatibility properties of as-cast TiNi alloys. Metals. 2025;15(7):758. https://doi.org/10.3390/met15070758

14. Yang C., Long T., Yan A., Ma H., Lu H., Liang L., Cai W. Improved corrosion resistance of selective laser melted NiTi alloys via nanosecond pulsed laser annealing treatment for biomedical application. Additive Manufacturing Letters. 2025;14:100306. https://doi.org/10.1016/j.addlet.2025.100306

15. Hejazi M., Sassani F., Gagnon J., Hsiang Y., Phani A.S. Deformation mechanics of self-expanding venous stents: Modelling and experiments. Journal of Biomechanics. 2021; 120:110333. https://doi.org/10.1016/j.jbiomech.2021.110333

16. Gordeev G.A., Krivilyov M.D., Ankudinov V.E. Сomputer simulation of selective laser melting of fine-grained metallic powders. Computational Continuum Mechanics. 2017;10(3):293–312. https://doi.org/10.7242/1999-6691/2017.10.3.23

17. Zhang W., Li Z., Chai M., Dong P., Wang Y. Selective laser melting of NiTi cardiovascular stents: Processibility, surface quality and mechanical properties. Optics & Laser Technology. 2025;181(1–2):111842. https://doi.org/10.1016/j.optlastec.2024.111842

18. Ji H., Zhang W., Li Z., Chai M., Wang Y. Experimental study of NiTi alloy cardiovascular stent formed via SLM. Materials Today Communications. 2024;41:110426. https://doi.org/10.1016/j.mtcomm.2024.110426

19. Marchenko E.S., Baigonakova G.A., Garin A.S., Kulbakin D.E., Zheronkina K.A., Tkachev D.A., Choinzonov E.L. Effect of SLM parameters on structure and mechanical properties of porous NiTi scaffolds. Progress in Additive Manufacturing. 2026;11(1):999–1013. https://doi.org/10.1007/s40964-025-01393-x

20. Zhang W., Li Z., Xu C., Chai M., Dong P. Surface characteristics of NiTi cardiovascular stents by selective laser melting and electrochemical polishing. The International Journal of Advanced Manufacturing Technology. 2024;130(1–2):623–634. https://doi.org/10.1007/s00170-023-12734-x

21. Yan L., Soh S.L., Wang N., Ma Q., Lu W.F., Dheen S.T., Kumar A.S., Fuh J.Y.H. Evaluation and characterization of nitinol stents produced by selective laser melting with various process parameters. Progress in Additive Manufacturing. 2022;7(6):1141–1153. https://doi.org/10.1007/s40964-022-00289-4

22. Vashishtha H., Jamshidi P., Vrettou A., Kareer A., Goode M., Deyhle H., James A., Ahmad S., Reinhard C., Attallah M., Collins D.M. Microscale stress-geometry interactions in an additively manufactured NiTi cardiovascular stent: A synchrotron dual imaging tomography and diffraction study. Materials Characterization. 2024;213:114016. https://doi.org/10.1016/j.matchar.2024.114016

23. Chernyshikhin S.V., Zhevnenko S.N., Zakirov A.V., Kor­neev B.A., Belousov S.A., Bogdanova M.V., Ego­rov V.Yu., Zherebtsov D.D., Lyange M.V., Shish­kovsky I.V. Surface tension measurements of NiTi alloy for the melt pool simu­lation during Laser Powder Bed Fusion. Materials Letters. 2026;405:139696. https://doi.org/10.1016/j.matlet.2025.139696

24. Kilina P.N., Sirotenko L.D., Kozlov M.S., Drozdov A.A. Quality assurance thermophysical aspects of highly porous implants with cellular structure obtained by selective laser melting. Russian Journal of Biomechanics. 2023;27(4(102)):200–211. https://doi.org/10.15593/rzhbiomeh/2023.4.16

25. Wiesent L., Spear A., Nonn A. Computational analysis of the effects of geometric irregularities on the interaction of an additively manufactured 316L stainless steel stent and a coronary artery. Journal of the Mechanical Behavior of Biomedical Materials. 2022;125:104878. https://doi.org/10.1016/j.jmbbm.2021.104878

26. Carbonaro D., Ferro N., Mezzadri F., Gallo D., Audenino A.L., Perotto S., Morbiducci U., Chiastra C. Easy-to-use formulations based on the homogenization theory for vascular stent design and mechanical characterization. Computer Methods and Programs in Biomedicine. 2024;257:108467. https://doi.org/10.1016/j.cmpb.2024.108467

27. Guo D., Wang Q., Liu L., Liu S., Cao H., Xie J., Yin F. Damping and compressive properties of SLM-fabricated rhombic dodecahedron-structured Ni–Ti shape memory alloy foams. Metals. 2025;15(3):335. https://doi.org/10.3390/met15030335

28. Zhang Z., Gao J., Wei S., Song B., Yao Y., Zheng X., Zhang Y., Zhang L., Li Q., Wu J., Shi Y. Lattice-inspired NiTi-based metamaterials with widely tunable mechanical-superelastic synergy. Virtual and Physical Prototyping. 2025;20(1):e2444572. https://doi.org/10.1080/17452759.2024.2444572

29. Sufiiarov V.S., Orlov A.V., Borisov E.V., Sokolova V.V., Chukovenkova M.O., Soklakov A.V., Mikhaluk D.S., Popovich A.A. Modeling the mechanical properties of lattice structures made by selective laser melting. Letters on Materials. 2020;10(2):123–128. https://doi.org/10.22226/2410-3535-2020-2-123-128

30. Marchenko E.S., Zheronkina K.A., Baigonakova G.A., Yasenchuk Yu.F., Chernyshikhin S.V., Garin A.S., Mono­genov A.N. Mechanical properties of cellular structures fabricated by laser powder bed fusion of TiNi powder. Journal of Alloys and Compounds. 2025;1044:184647. https://doi.org/10.1016/j.jallcom.2025.184647

31. Jiang H., Ziegler H., Zhang Z., Zhang H., Le Barbenchon L., Atre S., Chen Y. 3D printed tubular lattice metamaterials for mechanically robust stents. Composites Part B: Engineering. 2022;236:109809. https://doi.org/10.1016/j.compositesb.2022.109809

32. Zhang Y., Attarilar S., Wang L., Lu W., Yang J, Fu Y. A review on design and mechanical properties of additively manufactured NiTi implants for orthopedic applications. International Journal of Bioprinting. 2021;7(2):340. https://doi.org/10.18063/ijb.v7i2.340

33. Langi E., Zhao L.G., Jamshidi P., Attallah M.M., Silberschmidt V.V., Willcock H, Vogt F. Microstructural and mechanical characterization of thin-walled tube manufactured with selective laser melting for stent application. Journal of Materials Engineering and Performance. 2021;30(1): 696–710. https://doi.org/10.1007/s11665-020-05366-9

34. Andani M.T., Saedi S., Turabi A.S., Karamooz M.R., Haberland C., Karaca H.E., Elahinia M. Mechanical and shape memory properties of porous Ni50.1Ti49.9 alloys manufactured by selective laser melting. Journal of the Mechanical Behavior of Biomedical Materials. 2017;68: 224–231. https://doi.org/10.1016/j.jmbbm.2017.01.047