S. Bassaki, F. Golestani Fard, R. Naghizadeh, M. Rashidzadeh,
Volume 34, Issue 3 (12-2015)
Abstract
Titanium dioxide-nickel oxide porous coatings were synthesized by Plasma Electrolytic Oxidation (PEO)/ ElectroPhoretic Deposition (EPD) in one step and within a short time. The main purpose of this research was to increase photocatalytic activity of titanium oxide by increasing surface area and coupling of titanium oxide with nickel oxide. Applied voltage effects on phase structure, surface morphology and photocatalytic efficiency of coatings were studied. Phase structure and surface morphology of the synthesized catalysts were investigated by XRD and SEM, respectively. Photocatalytic efficiency of the samples was studied through measuring the decomposition rate of 4-chlorophenol. The results showed that the coatings mainly consisted of anatase and nickel oxide phases whose amounts in coatings increased with the voltage. There was an enhancement of the photocatalytic efficiency in TiO2/NiO composite coatings compared with TiO2 coatings. Besides, there was an optimum amount of NiO to reach maximum photocatalytic efficiently.
M. Toorani Farani,
Volume 39, Issue 1 (5-2020)
Abstract
In this study, Plasma Electrolytic Oxidation (PEO) at three frequencies of 500, 1000 and 3000 Hz was applied on Mg surface and the effect of PEO surface preparation on protective behavior of three types of epoxy, fusion bond epoxy (FBE) and polyurethane coatings was investigated. The microstructural and protective properties of PEO coatings were studied by SEM, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). The results showed that the coating formed at frequency of 3000 Hz had smaller pore size and better protection properties. EIS test in 3.5 Wt.% NaCl solution was also used to investigate the protective behavior of the two-layered coatings. The results showed that PEO process had a favorable effect on the protective behavior of the polymer layers. Moreover, the best protection behavior was related to the PEO/FBE coating system.
S. Shahzamani, M. R. Toroghinejad, A. Asharfi,
Volume 40, Issue 2 (9-2021)
Abstract
In this study, Al/Al2O3 composite was produced by accumulative roll bonding (ARB) process coupled with the plasma electrolytic oxidation (PEO) process. The alumina was grown on Al sheets by electrolyte technique with three different thicknesses (10, 20, and 40 µm). The results showed that incorporation of alumina up to 3.22 vol.% in aluminum matrix enhanced the yield and tensile strength of the composite, whereas increasing the amount of alumina up to 6.25 vol.% deteriorated the tensile properties. In the last part, a serial sectioning process was employed to develop a three-dimensional (3D) representation of the microstructure of Al2O3 particles reinforced Al composite for visualization and finite-element modeling (FEM).
