| Plasma Electrolytic Oxidation coating on E21 magnesium alloy |
| کد مقاله : 1006-CNF |
| نویسندگان |
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فاطمه پوریعقوب * دانشگاه تربیت مدرس-گروه شیمی |
| چکیده مقاله |
| In this study, the electrolytic plasma oxidation method was used to form a ceramic coating on the E21 magnesium alloy, by using an alternate power source (AC) and a silicate-based electrolyte with and without the addition of zinc oxide (ZnO) nanoparticles. The effect of this additive on microstructure, chemical composition and corrosion properties of coatings was investigated using scanning electron microscopy, X-ray diffraction pattern, elemental analysis, potentiodynamic polarization test and electrochemical impedance spectroscopy test. The results of EDS analysis and elemental mapping analysis, showed the presence of Zn element and its uniform distribution on the surface of coatings containing nanoparticles. XRD analysis confirmed the presence of ZnO phase in the formed coatings in the electrolyte containing ZnO nanoparticle. These particles were placed in the poroses and cracks of the coating and reduced the defects of the coating. Evaluation of TOEFL polarization test results showed a decrease in corrosion current density and an increase in corrosion potential and polarization resistance of samples containing ZnO nanoparticles compared to the sample without these particles. In electrochemical impedance spectroscopy, the impedance modulus of the coated samples was increased by adding ZnO nanoparticles into the coated electrolyte. Also, based on the data obtained from fitting the results of this test, the resistances of the inner and outer layers of these coatings increased to the coating without nanoparticles. Therefore, the results of corrosion tests show that the corrosion performance of the coating is improved by adding ZnO nanoparticles to the coating electrolyte, because by reducing structural defects, they partially block the entry paths of corrosive ions to the surface. |
| کلیدواژه ها |
| Plasma electrolytic oxidation, corrosion resistance, ceramic coating, magnesium alloy |
| وضعیت: چکیده برای ارائه به صورت پوستر پذیرفته شده است |