Analysis of XPS results of AISI 316L SS electropolished and magnetoelectropolished at varying conditions

et al. 2016

In the paper, the fabrication method and characteristics of porous coatings on Ti-Nb-Zr-Sn alloy biomaterial obtained by plasma electrolytic oxidation (PEO) are presented. The PEO process was performed at two voltages of 180 ± 10 and 450 ± 10 V, respectively, during 3 min of treatment in the electrolyte based on orthophosphoric acid with copper II nitrate of initial temperature of 20 ± 2°C. Scanning electron microscopy (SEM) with energy-dispersive X-ray spectroscopy (EDS), glow discharge optical emission spectroscopy (GDOES), Xray photoelectron spectroscopy (XPS) and 2D roughness measurements were performed on the samples. The study results indicate an enrichment of the porous layer (18 and 21 μm thick, for 180 and 450 V, respectively)

Section: Introductionmentioning

confidence: 99%

Investigation of porous coatings obtained on Ti-Nb-Zr-Sn alloy biomaterial by plasma electrolytic oxidation: characterisation and modelling

et al. 2016

“…Plasma electrolytic oxidation (PEO) known also as the micro arc oxidation (MAO) [1][2][3][4] as well as electrochemical polishing (EP) [5], magnetoelectropolishing (MEP) [5][6][7][8][9], and/or high-current density electropolishing (HDEP) [10,11] operations performed on metals or alloys results in the formation of the surface layer with different specific mechanical [12,13] and corrosion properties [9,14]. These layers are generally characterized by different chemical compositions [15][16][17][18] than that of the matrix itself.…”

Section: Introductionmentioning

confidence: 99%

“…Numerous published papers presenting scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/ EDS), X-ray diffraction analysis (XRD), X-ray photoelectron spectroscopy (XPS), and secondary ion mass spectroscopy (SIMS) results indicate that the surface layers formed after each of the EP, MEP, HDEP, and PEO treatments have different chemical compositions and structure (various crystalline and/or amorphous forms) than those of the native matrices [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18]. Some of them obtained by EP, MEP, and HDEP are passive, and others obtained in PEO/MAO operations are open thick porous layers, generally non-passive [1][2][3][4].…”

Section: Introductionmentioning

confidence: 99%

Development of plasma electrolytic oxidation for improved Ti6Al4V biomaterial surface properties

2015

In the paper, the scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and Xray photoelectron spectroscopy (XPS) results of the Ti6Al4V alloy treated by a novel plasma electrolytic oxidation (PEO) (micro arc oxidation) in the electrolyte containing concentrated phosphoric acid and copper nitrate are presented. The PEO treatment was performed at the voltage of 450±10 V. The main problem to solve under the experiments was to obtain a porous surface layer composed mainly of titanium phosphates within the copper ions. The performed study has shown that the amount of copper nitrate in 85 % concentrated phosphoric acid should be not less than 1

“…Among the preparation methods of surface nano-layers with controlled mechanical or electrochemical properties, electropolishing (EP) [1][2][3][4][5], magnetoelectropolishing (MEP) [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19], and high-current-density electropolishing (HDEP) [20][21][22] have been previously shown to be highly efficient. The obtained surface nano-layers, which are mostly passive, may be treated as nano-coatings with determined chemical composition, which is different than that one of matrix.…”

Section: Introductionmentioning

confidence: 99%

Development of copper-enriched porous coatings on ternary Ti-Nb-Zr alloy by plasma electrolytic oxidation

et al. 2016

In this paper, a preparation method and characteristics of porous coatings enriched in copper distributed in the whole volume on a ternary Ti-Nb-Zr alloy biomaterial obtained by plasma electrolytic oxidation (PEO) in an electrolyte containing H 3 PO 4 within Cu(NO 3 ) 2 at potentials of 180 and 450 V are presented. It has been shown that the PEO potential has impact on the thickness of the coatings, i.e., the higher the potential used, the thicker the coating obtained. Using XPS study, it was shown that copper inside the coating appears as Cu + and Cu 2+ ions, while titanium, niobium, and zirconium appear as Ti 4+ , Nb 5+ , and Zr x+ (x ≤ 2), respectively. It was also found that the roughness of PEO coating formed at 450 V is higher than the one obtained at 180 V, and it is well correlated with bigger pores after the PEO treatment. Additionally, in this paper two PEO coating models composed of three sub-layers are presented. The thickness of the outer top porous sub-layer obtained after PEO oxidation at both 180 and 450 V equals to about 2 μm, while the semi-porous as well as transition sub-layers are thicker after PEO processing at 450 V (5 μm) than those obtained at 180 V (4 μm thick). The creation of the top porous and transition compact sub-layer of PEO coating may be explained by switch-on and switch-off of the PEO potential, while the middle and semi-porous sub-layers are most likely formed during the stable voltage conditions of PEO treatment.