In-depth study of the influence of electrolyte composition on coatings prepared by plasma electrolytic oxidation of TA6V alloy

Abstract

OATAO is an open access repository that collects the work of some Toulouse researchers and makes it freely available over the web where possible. This is version published in:Official URL: To cite this version:A B S T R A C T Coatings were prepared on TA6V alloy by plasma electrolytic oxidation (PEO) using a standard electrical signal. Influence of electrolyte composition on coating characteristics was then extensively studied using four electrolytes of increasing complexity, containing KOH, Na 2 SiO 3 and NaAlO 2 . The combination of SEM, GDOES, XRD characterizations on the one hand and of thermodynamic calculations on the other hand, deeply clarified coating compositions, showing in particular that they include both amorphous and crystalline phases. Amorphous phase resulted directly from the presence of silicate in solution, and was made of complex Si-based oxides difficult to clearly identify. Depending on electrolyte composition, crystalline phases in coatings included simple oxide (i.e. anatase and rutile TiO 2 ) and/or mixed oxide (Al 2 TiO 5 ), resulting from both substrate oxidation and deposition from electrolyte. Therefore, this study successfully offered an innovative approach, combining both experimental characterizations and thermodynamic calculations, to study and tune chemical characteristics of PEO coatings on TA6V.

Insights into self-healing behavior and mechanism of dicalcium phosphate dihydrate coating on biomedical Mg

“…Fig. 11 (a) illustrates the correlation curves of ΔG as a function of pH calculated using the PHREEQC program [ 32 ]. The original DCPD coatings on pure Mg are unstable and tend to be dissolved out of pH range from 7.6 to 8.2 in Hank's solution as well as from 7.8 to 8.0 in NS solution.…”

“…The pH-sensitive behavior was evaluated by thermodynamic analysis and ion release experiments. The thermodynamic parameters were calculated using PHREEQC software [ 32 ] to reveal the association/dissociation reactions of Ca–P compounds in physiological solutions. The details on thermodynamic calculation methods were provided in Supplementary Material .…”

The Tribological Behavior of Nanocrystalline TiO2 Coating Produced by Plasma Electrolytic Oxidation

“…Ti and its alloys have some desirable properties, including low density, low elastic modulus, high strength-to-weight ratio, high melting point, and great biocompatibility, as well as good corrosion, creep, and fatigue resistance [1,2]. However, Ti has some disadvantages, including high friction coefficient, low abrasive, low adhesive wear resistance (weak tribological properties) [3][4][5].…”

Effect of Isothermal Heat Treatment at 760 °C on the Oxidation Behavior of Ti-Al-Zr Alloy

“…[37] GDOES has been used by investigators for analysis of metallic coatings [38,39] and thin films. [40] It has been used by researchers for depth analysis of passive films [41] and corrosion layers, [42] for electrodeposited and electrochemical films, [43][44][45][46][47][48] to characterize the industrial surface treatment phenomena [49][50][51][52] and for the characterization of high-temperature oxide. [53][54][55][56][57] The investigation by several researchers on the oxidation kinetics and alpha case formation in various titanium alloys established that material composition (i.e., alloying element) and microstructure significantly influence the oxidation kinetics and depth of the alpha case.…”