Effects of crystallographic orientation on corrosion behavior of magnesium single crystals
Data(s) |
01/01/2012
|
---|---|
Resumo |
The corrosion behavior of magnesium single crystals with various crystallographic orientations was examined in this study. To identify the effects of surface orientation on the corrosion behavior in a systematic manner, single-crystal specimens with ten different rotation angles of the plane normal from the [0001] direction to the [1010] direction at intervals of 10° were prepared and subjected to potentiodynamic polarization and potentiostatic tests as well as electrochemical impedance spectroscopy (EIS) measurements in 3.5 wt.% NaCl solution. Potentiodynamic polarization results showed that the pitting potential (E <sub>pit</sub>) first decreased from −1.57 V <sub>SCE</sub> to −1.64 V <sub>SCE</sub> with an increase in the rotation angle from 0° to 40°, and then increased to −1.60 V <sub>SCE </sub>with a further increase in the rotation angle to 90°. The results obtained from potentiostatic tests are also in agreement with the trend in potentiodynamic polarization tests as a function of rotation angle. A similar trend was also observed for the depressed semicircle and the total resistances in the EIS measurements due to the facile formation of MgO and Mg(OH)<sub>2</sub> passive films on the magnesium surface. In addition, the amount of chloride in the passive film was found first to increase with an increase in rotation angle from 0° to 40°, then decrease with a further increase in rotation angle, indicating that the tendency to form a more protective passive film increased for rotation angle near 0° [the (0001) plane] or 90° [the (1010) plane]. <br /> |
Identificador | |
Idioma(s) |
eng |
Publicador |
Springer New York LLC |
Relação |
http://dro.deakin.edu.au/eserv/DU:30047969/nam-effectsof-2012.pdf http://dx.doi.org/10.1007/s11837-012-0334-0 |
Direitos |
2012, TMS |
Palavras-Chave | #corrosion behaviour #magnesium single crystals #crystallographic orientation |
Tipo |
Journal Article |