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This study investigates the in vitro biocompatibility, corrosion resistance, and adhesion strength of a gas abrasive-treated Ti6Al4V alloy, alongside microplasma-sprayed titanium and tantalum coatings. Employing a novel approach in selecting microplasma spray parameters, this study successfully engineers coatings with tailored porosity, roughness, and over 20% porosity with pore sizes up to 200 μm, aiming to enhance bone in-growth and implant integration. This study introduces an innovative methodology for quantifying surface roughness using laser electron microscopy and scanning electron microscopy, facilitating detailed morphological analysis of both the substrate and coatings. Extensive evaluations, including tests for in vitro biocompatibility, corrosion resistance, and adhesive strength, revealed that all three materials are biocompatible, with tantalum coatings exhibiting superior cell proliferation and osteogenic differentiation, as well as the highest corrosion resistance. Titanium coatings followed closely, demonstrating favorable osteogenic properties and enhanced roughness, which is crucial for cell behavior and attachment. These coatings also displayed superior tensile adhesive strengths (27.6 ± 0.9 MPa for Ti and 28.0 ± 4.9 MPa for Ta), surpassing the ISO 13179-1 standard and indicating a robust bond with the substrate. Our findings offer significant advancements in biomaterials for medical implants, introducing microplasma spraying as a versatile tool for customizing implant coatings, particularly emphasizing the superior performance of tantalum coatings in terms of biocompatibility, osteogenic potential, and corrosion resistance. This suggests that tantalum coatings are a promising alternative for enhancing the performance of metal implants, especially in applications demanding high biocompatibility and corrosion resistance. [ABSTRACT FROM AUTHOR]

By means of scanning electron microscopy, atomic-force microscopy, X-ray fluorescence analysis, and X-ray spectral microanalysis it was shown that, under plasma-electrolytic oxidation (PEO) of titanium alloys in pyrophosphate electrolytes, well-adhered oxide coatings with microglobular morphology result. It was demonstrated that the chemical and phase composition of the coatings, as well as the surface topography and grain size, can be controlled by changing the concentration of a pyrophosphate electrolyte and a PEO current density. It was established that the resulting oxide layer is highly resistant to abrasive wear and enhances the titanium corrosion resistance in model media (Ringer’s solution) substantially, which suggests that the coatings are promising for use in biological applications. [ABSTRACT FROM AUTHOR]

The aim of the present article is to investigate the corrosion resistance of the Zr-Ti-Si-O coatings (as-deposited and annealed) as possible candidate as new biocompatible material. The coatings have been characterized in terms of elemental and phase composition, roughness and corrosion resistance in simulated body fluid (SBF) at 37 °C. The coatings, with a compositional ratio O/(Zr + Ti + Si) of 1.38, were found to consist of a mixture of ZrTiO4, ZrSiO4, Ti2O3, and SiOx phases. The samples annealed in O2 atmosphere at 1100 °C for 30 min resulted in improved crystallinity, increased surface area, surface roughness, and skewness. The results of the electrochemical tests revealed that Zr-Ti-Si-O coatings had improved the corrosion resistance to the aggressive attack of the SBF as compared to the bare Ti6Al4V alloy, the best results being obtained on annealed coatings. [ABSTRACT FROM AUTHOR]

Because of their superior properties, titanium aluminium nitride (TiAlN) films are increasingly applied as protective layers on cutting and forming tools and turbine compressor blades and as biocompatible barriers. TiAlN films were deposited on AISI 316L stainless steel substrates by reactive magnetron sputtering using a target consisting of equal segments of titanium and aluminium. X-ray diffraction characterisation showed that the coating structure was face centred cubic. AFM and SEM studies indicated that the coatings are regular with dense shpherical granular structure. The coatings were also characterised using photoluminescence spectroscopy and Raman microscopy to elucidate the optical and acoustic phonon modes of the cubic lattices. Characteristic peaks were observed at 250, 620 and 1180 cm-1 in laser Raman studies. Polarisation and impedance spectroscopy studies on TiAlN and TiN coated specimens were conducted in Fusuyama simulated body fluid. The charge transfer resistance Rct increased in the order: uncoated 316L substrate; 2 μm TiN film; 3 μm TiN film; 2 μm TiAlN film. Thus, the TiAlN coating has the highest corrosion resistance, and was also found to have the most noble corrosion potential and lowest corrosion rate in the polarisation tests. [ABSTRACT FROM AUTHOR]