کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1623836 | 1516413 | 2008 | 7 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Effect of (NaPO3)6 concentrations on corrosion resistance of plasma electrolytic oxidation coatings formed on AZ91D magnesium alloy Effect of (NaPO3)6 concentrations on corrosion resistance of plasma electrolytic oxidation coatings formed on AZ91D magnesium alloy](/preview/png/1623836.png)
Different plasma electrolytic oxidation (PEO) coatings were prepared on AZ91D magnesium alloy in electrolytes containing various concentrations of (NaPO3)6. The morphologies, chemical compositions and corrosion resistance of the PEO coatings were characterized by environmental scanning electron microscopy (ESEM), X-ray diffractometer (XRD), energy dispersive analysis of X-rays (EDAX), potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) test. The results showed that the PEO coatings were mainly composed of MgO, Mg2SiO4, MgAl2O4 and amorphous compounds. As the (NaPO3)6 concentrations increased from 0 to 10 g/l, the thickness and surface roughness of the coatings approximately linearly increased; the MgO and Mg2SiO4 phase increased within the concentration range of 0–3 and 0–5 g/l, and then decreased within the range of 3–10 and 5–10 g/l, respectively, while the MgAl2O4 phase gradually decreased. Moreover, the corrosion resistance of the coatings increased within the range of 0–5 g/l and then decreased within the range of 5–10 g/l. The best corrosion resistance coating was obtained in electrolyte containing 5 g/l (NaPO3)6, it had the most compact microstructure. Besides, a reasonable equivalent circuit was established, and the fitting results were consistent with the results of the EIS test.
Journal: Journal of Alloys and Compounds - Volume 464, Issues 1–2, 22 September 2008, Pages 537–543