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In this study, the influence of the electrochemical oxidation process on Ti-Grad 23 alloy (Ti6Al4V ELI) in 1 M H3PO4, under applied voltages between 200 and 275 V, at a constant time of 1 min, is analyzed. The structural, morphological, and wettability properties of the TiO2 anodic layers obtained were investigated by X-ray diffraction (XRD), energy dispersive electron microscopy (SEM-EDS), contact angle measurements, and chemical corrosion. XRD analysis showed the development and intensification of anatase and brookite phases, with increased crystallite size after electrochemical oxidation. SEM/EDS characterization confirmed the formation of an inhomogeneous porous TiO2 layer, with pore diameters ranging from 98 to 139 nm and a significant increase in oxygen content. Contact angle measurements demonstrate enhanced hydrophilicity for all oxidized samples, with progressively lower values as the applied voltage increased. Chemical corrosion tests in Ringer solution and Ringer + 40 g/L H2O2 indicated that oxidized surfaces maintain structural stability in physiological media, whereas exposure to oxidizing environments induces partial pore closure and crack formation due to localized corrosion. The optimal anodizing condition was identified at 200 V for 1 min, yielding a uniform distribution of pores and improved morpho-functional characteristics suitable for biomedical applications. The optimal electrochemical oxidation conditions were identified at 200 V for 1 min, ensuring a uniform pore distribution.

The present work investigates the electrochemical behavior of the Zr2.5Nb alloy in a biomedical context, emphasizing the influence of electrochemical oxidation treatment on its stability in simulated physiological environments. The alloy samples were oxidized in 1 M H2SO4 under controlled voltages (200–275 V) and times (1 min), identifying 200 V–1 min as the optimal condition for obtaining a uniform porous oxide layer with an average pore diameter of ~90 nm. The corrosion resistance was evaluated using open circuit potential (OCP) and electrochemical impedance spectroscopy (EIS) in Ringer’s solution and Ringer’s solution containing 40 g/L H2O2 to simulate physiological and inflammatory conditions. Electrochemical tests revealed that electrochemically oxidized samples exhibited a polarization resistance up to 14.78 MΩ·cm2, about 26 times higher than that of the untreated alloy (0.56 MΩ·cm2). After 77 h of immersion, the oxidized alloy maintained a high resistance (17.54 MΩ·cm2), confirming long-term stability. Scanning Electron Microscopy (SEM–EDX) and X-Ray Diffraction (XRD) analyses highlighted significant increases in oxygen content and the transformation from the monoclinic baddeleyite to the cubic arkelite phase of ZrO2, contributing to enhanced corrosion resistance. These findings demonstrate that controlled electrochemical oxidation significantly improves the durability of Zr2.5Nb alloy in oxidative environments, supporting its potential for long-term biomedical implant applications.

Pure titanium (Ti) is investigated in a pre-clinical study in Hank’s biological solution using electrochemical methods, open circuit potential, and electrochemical impedance spectroscopy to highlight the time effect in extreme body conditions, such as inflammatory diseases, on degradability due to corrosion processes occurring on the titanium implant. Electrochemical impedance spectroscopy (EIS) data are presented as Nyquist and Bode plots. The results show the increasing reactivity of titanium implants in the presence of hydrogen peroxide, which is an oxygen-reactive compound that describes inflammatory conditions. The polarization resistance, which results from electrochemical impedance spectroscopy measurements, declined dramatically from the highest value registered in Hank’s solution to smaller values registered in all solutions when different concentrations of hydrogen peroxide were tested. The EIS analysis provided insights into titanium’s in vitro corrosion behavior as an implanted biomaterial, which could not be solely obtained through potentiodynamic polarization testing.

This study aims to investigate the anticorrosive properties of Zr2.5Nb alloy intended for possible applications in the human body; it was tested for 2 days in Ringer solution (an artificial analogue for human blood, considered the most corrosive body fluid). For Zr2.5Nb samples, in situ electrochemical measurements to assess the anticorrosive properties were applied, such as open circuit potential (OCP), polarization resistance (Rp), potentiodynamic polarization (PD) and cyclic voltammetry (CV). The electrochemical results show that the Zr2.5Nb alloy shows a positive and stable trend according to the open circuit potential, but with a modest corrosion rate in the form of pitting, deduced from the analysis of the polarization resistance and cyclic voltammetry data.

In the field of healthcare and dentistry, 316L stainless steel is widely used for its corrosion resistance. However, the presence of lactic acid in salivary solutions can affect its surface reactivity. This study employed electrochemical methods to investigate the influence of lactic acid on 316L stainless steel’s corrosion resistance in Fusayama Meyer saliva and saliva doped with varying lactic acid concentrations. The results revealed a significant decrease in polarization resistance as the lactic acid concentration increased, despite a shift toward more positive corrosion potentials. Consequently, the study suggests that the lactic acid presence in salivary solutions should be considered when evaluating the corrosion susceptibility of 316L stainless steel devices.

This research work describes the effect of dispersed titanium carbide (TiC) nanoparticles into nickel plating bath on Ni/TiC nanostructured composite layers obtained by electro-codeposition. The surface morphology of Ni/TiC nanostructured composite layers was characterized by scanning electron microscopy (SEM). The composition of coatings and the incorporation percentage of TiC nanoparticles into Ni matrix were studied and estimated by using energy dispersive X-ray analysis (EDX). X-ray diffractometer (XRD) has been applied in order to investigate the phase structure as well as the corresponding relative texture coefficients of the composite layers. The results show that the concentration of nano-TiC particles added in the nickel electrolyte affects the inclusion percentage of TiC into Ni/TiC nano strucured layers, as well as the corresponding morphology, relative texture coefficients and thickness indicating an increasing tendency with the increasing concentration of nano-TiC concentration. By increasing the amount of TiC nanoparticles in the electrolyte, their incorporation into nickel matrix also increases. The hybrid Ni/nano-TiC composite layers obtained revealed a higher roughness and higher hardness; therefore, these layers are promising superhydrophobic surfaces for special application and could be more resistant to wear than the pure Ni layers.

The aim of this work was to obtain hybrid Co/UHMWPE composite biocoatings reinforced by UHMWPE (ultra high molecular weight polyethylene) biopolymer microparticles in the cobalt matrix, by electro-codeposition technique, with possibilities to use them as biomaterials. UHMWPE was selected as surface modifier element, due to its high biocompatibility and low coefficient of friction being used in many biomedical applications. Cobalt is already used in biomedical implants as cobalt – chromium alloys. The obtained coatings were investigated in terms of surface morphology (scanning electron microscopy - SEM), chemical composition and inclusion percentage (energy dispersive X-ray spectroscopy - EDX), roughness and microtopography (atomic force microscopy - AFM), coating thickness and microhardness. The SEM morphologies of electrodeposited pure cobalt and Co/UHMWPE composite biocoatings, show differences due to UHMWPE biopolymer particles incorporation in the cobalt matrix. The inclusion of UHMWPE microparticles increases with increasing the UHMWPE concentration in the electrolyte as was demonstrated by EDX investigations. The addition of the UHMWPE biopolymer microparticles to the deposition bath led to an increase of the roughness of hybrid coatings comparatively with pure cobalt coating obtained under the same conditions. The coating thickness of the electroplated surfaces as were observed by cross sectional scanning electron micrographs confirm higher adhesion strength of the coatings on the stainless steel support.

In this study Ni/nano-TiC functional composite coatings were produced by electro-codeposition of TiC nanoparticles (50 nm mean diameter) with nickel on 304L stainless steel support. Coatings were obtained from a Watts classical solution in which TiC nanoparticles were added. The surface morphology, chemical composition, structure, roughness and thickness, were evaluated in relation to the effect of TiC nanoparticles incorporation into Ni matrix. It was found that incorporation of TiC nanoparticles into the nickel matrix produces morphological changes in the deposit and increases the roughness. The fretting wear behavior in wet conditions of the obtained coatings was evaluated on a ball-on-plate configuration. To evaluate the wet fretting wear (tribocorrosion) behavior the open circuit potential was measured before, during and after the fretting tests at room temperature in the solution that simulates the primary water circuit of Pressurized Water Reactors. The results show that Ni/nano-TiC composite coatings exhibited a low friction coefficient, high nanohardness and fretting wear resistance in wet conditions compared with pure Ni coatings.

The electrodeposition method was used to obtain nanostructured layers of Co/nano-CeO2 on 304L stainless steel, from a cobalt electrolyte in which different concentrations of CeO2 nanoparticles (0, 10, 20, and 30 g/L) were dispersed. The electrodeposition was performed at room temperature using three current densities (23, 48, and 72 mA cm−2), and the time was kept constant at 90 min. The influence of current densities and nanoparticle concentrations on the characteristics of the obtained nanostructured layers is also discussed. An X-ray diffractometer (XRD) was used to investigate the phase structure and cobalt crystallite size of the nanostructured layers, and a contact angle (sessile drop method) was used to assess the wettability of the electrodeposited layers. The roughness of the surfaces was also studied. The results show that the nanostructured layers became more hydrophilic with increasing nanoparticle concentration and increasing current density. In the case of pure cobalt deposits, an increase in the current density led to an increase in the size of the cobalt crystallites in the electrodeposited layer, while for the Co/nano-CeO2 nanostructured layers, the size of the crystallites decreased with increasing current density. This confirms the nanostructuring effect of nano-CeO2 electrocodeposited with cobalt.

The corrosion of implant biomaterials is a well-known critical issue when they are in contact with biological fluids. Therefore, the reactivity of Ti6Al4V implant biomaterials is monitored during immersion in a Hanks’ physiological solution without and with added metabolic compounds, such as lactic acid, hydrogen peroxide, and a mixture of the two. Electrochemical characterization is done by measuring the open circuit potential and electrochemical impedance spectroscopy performed at different intervals of time. Electrochemical results were completed by morphological and compositional analyses as well as X-ray diffraction before and after immersion in these solutions. The results indicate a strong effect from the inflammatory product and the synergistic effect of the metabolic lactic acid and hydrogen peroxide inflammatory compound on the reactivity and corrosion resistance of an implant titanium alloy.