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Background: The porous SHS-TiNi alloy is a widely used material for repairing defects in bone tissues. Objective: The objective of the study is to comprehensively investigate porous SHS-TiNi alloy samples for fatigue strength under cyclic bending, to study deformation characteristics under quasistatic tension and bending, and to carry out the fractographic analysis of fracture features. Methods: The study employed the electrospark method for cutting plates from a porous isotropic SHS- TiNi rod 30 mm in diameter and 300 mm in length. Results: Deformation behaviour under tension and three-point bending of porous plates showed that porous samples undergo viscoelastic deformation due to the austenite-martensite (A->M) phase transformation. The fracture surfaces of elastic porous samples were studied by SEM. Microscopic studies of fracture surfaces revealed zones of quasi-brittle fracture of martensite and viscous fracture of austenite. The porous framework of intermetallic alloy exhibits a continuous brittle layer and numerous brittle non-metallic inclusions. However, successful fatigue tests showed that brittle phases and inclusions do not significantly affect deformation and fatigue characteristics of porous titanium nickelide. It was found that 70% of porous samples sustain 106 cycles of deformation without fracture due to reversible A->M->A phase transformations in the TiNi phase, which is one of the components of multiphase porous alloy. Conclusion: Viscoelastic behavior of the porous sample and its high fatigue strength under cyclic loading is due to reversible deformation of the TiNi phase. The corrosion-resistant layer of the porous framework allows an effective use of SHS-TiNi.