The corrosion resistance of nanostructured nitinol (NiTi) was investigated using long-term tests in solutions simulating physiological fluids at static conditions, reflecting the material structure and metal concentration in the solutions. Mechanical polishing reduced the ion release by a factor of two to three, whereas annealing deteriorated the corrosion resistance. The depassivation and repassivation of nitinol surfaces were considered. We found that nanostructured nitinol might increase the corrosion leaching of titanium into solutions, although the nickel release decreased. Metal dissolution did not occur in the alkaline environment or artificial plasma. A Ni-free surface with a protective 25 nm-thick titanium oxide film resulted from soaking mechanically treated samples of the NiTi wire in a saline solution for two years under static conditions. Hence, the medical application of nanostructured NiTi, such as for the production of medical devices and implants such as stents, shows potential compared with microstructured NiTi.

A Ti–25Nb–13Ta–5Zr alloy was produced and studied in this work, and plates and wires were made from this alloy. It is shown that the Ti–25Nb–13Ta–5Zr alloy has the required mechanical properties and a β-crystal phase. Microstructures were present on the surface of the alloy with a height of several hundred nm, located at a distance of 1.5–2 μm from each other. Ti–25Nb–13Ta–5Zr was superior to nitinol in terms of the formation of long-living reactive protein species and the generation of reactive oxygen species. Cell cultivation on Ti–25Nb–13Ta–5Zr alloy surfaces revealed a significant mitotic index (2%) and a small number of nonviable cells (<5%). The cells were actively attached and spread over the alloy. The biocompatibility of Ti–25Nb–13Ta–5Zr was verified by experiments on the implantation of the alloy in the form of plates and coiled wires. The surface morphology of the specimens after biological trials was not significantly altered. The experimental data we obtained suggest that Ti–25Nb–13Ta–5Zr is suitable for potential applications in biology and medicine.

The work described in this article is aimed at investigating the properties of a group of Ti-Zr-Nb alloys. In modern orthopedics and traumatology, the use of materials for bone implants with a minimum modulus of elasticity is becoming increasingly important. This is due to a number of advantages that allow for better integration of the implants with the bone tissue, including the reduction in the detrimental effect of the load-shielding effect, a better load distribution, and stress distribution, which allows for increasing the life of the implant. It is known that the lowest modulus of elasticity in titanium alloys at normal temperature is achieved by the phase composition consisting of metastable β-phase. It is possible to achieve the desired structure by a combination of alloy composition selection and heat treatment. Quenching of titanium alloys allows for the high-temperature β-phase to be fixed. This paper provides justification of the choice of compositions of the studied alloys by calculation methods. The structure of alloys after melting in a vacuum electric arc furnace in an argon environment was studied. The ingots obtained had a dendritic structure. Homogenizing annealing in a vacuum furnace at 1000 °C for 4 h was used to equalize the composition. The structure of the alloyed sheets after hot rolling and hot rolling and quenching was investigated. The microstructure of the plates in both variants had uniform grains of polyhedral shape. X-ray phase analysis of the plates showed that the content of metastable β-phase was 100% before and after quenching. Microhardness testing of the plates showed no significant effect of quenching. The result of the mechanical properties study showed an increase in the plasticity of the material after quenching, with the tensile plots of the samples after quenching reflecting the area where the reverse phase transition of β’<-> α’’ occurs. Mechanical studies by cyclic loading showed the presence of a superelasticity effect. The Young’s modulus study gave a result of 51 GPa for one of the compositions studied. The combination of properties of the materials under investigation has the potential for promising use as a basis for bone implants.

A new medical antibacterial corrosion-resistant steel alloyed with silver and titanium was smelted. The optimal conditions for homogenizing annealing were selected to obtain a uniform structure and give rise to equiaxed grains. The mechanical properties, microstructure, and phase composition were studied. X-ray powder diffraction analysis showed that the steel without alloying elements after rolling has an austenitic structure. The alloying gave rise to a small amount of ferrite in the steel structure. Spectral analysis showed a uniform silver distribution throughout the alloy. It was determined that a steel sample containing silver and titanium has an antibacterial effect on the bacterial strain Pseudomonas marginalis.

Titanium-based alloy with low-toxic metals such as niobium, tantalum and zirconium (TiNbTaZr) was manufactured. The primary weight percentages of elements used for fusion were: titanium, 65%;...

Hip joint implants are among the most prevalent types of medical implants utilized for the replacement of damaged joints. The utilization of modern implant materials, such as cobalt–chromium alloys, stainless steel, titanium, and other titanium alloys, is accompanied by challenges, including the toxicity of certain elements (e.g., aluminum, vanadium, nickel) and excessive Young’s modulus, which adversely impact biomechanical compatibility. A mismatch between the stiffness of the implant material and the bone tissue, known as stress shielding, can lead to adverse outcomes such as bone resorption and implant loosening. Recent studies have shifted the focus to β-titanium alloys due to their exceptional biocompatibility, corrosion resistance, and low Young’s modulus, which is close to the Young’s modulus of bone tissue (10–30 GPa). In this study, the microstructure, mechanical properties, and phase stability of the Ti-38Zr-11Nb alloy were investigated. Energy dispersion spectrometry was employed to confirm the homogeneous distribution of Ti, Zr, and Nb in the alloy. A subsequent microstructural analysis revealed the presence of elongated β-grains subsequent to rolling and quenching. Furthermore, grinding contributed to the process of recrystallization and the formation of subgrains. X-ray diffraction analysis confirmed the presence of a stable β-phase under any heat treatment conditions, which can be explained by the use of Nb as a β-stabilizer and Zr as a neutral element with a weak β-stabilizing effect in the presence of other β-stabilizers. Furthermore, the modulus of elasticity, as determined by tensile testing, exhibited a decline from 85 GPa to 81 GPa after annealing. Mechanical tests demonstrated a substantial enhancement in tensile strength (from 529 MPa to 628 MPa) concurrent with a 32% reduction in elongation to fracture of the samples. These alterations are attributed to microstructural transformations, including the formation of subgrains and the rearrangement of dislocations. This study’s findings suggest that the Ti-38Zr-11Nb alloy has potential as a material of choice due to its lower Young’s modulus compared to traditional materials and its stable β-phase, which enhances the implant’s durability and reduces the risk of brittle phases forming over time. This study demonstrates that the corrosion resistance of titanium grade 2 and Ti-38Zr-11Nb is comparable. The material in question exhibited no evidence of cytotoxic activity in the context of mammalian cells.