Application of Voltage Pulse Transient Analysis during Plasma Electrolytic Oxidation for Assessment of Characteristics and Corrosion Behaviour of Ca- and P-containing Coatings on Magnesium
发布时间：2021-07-12
点击次数：
影响因子：6.901
DOI码：10.1016/j.electacta.2014.10.063
发表刊物：ELECTROCHIMICA ACTA
摘要：Pulsed unipolar plasma electrolytic oxidation (PEO) processes for magnesium and resultant Ca- and P-containing coatings were investigated. Electrical waveforms of the PEO process were quantitatively studied, and correlated with the coating characteristics. It was found that the system relaxation during the voltage pulse-off period included capacitor discharging and dielectric relaxation of the coating material. The extent of the latter depended on the pulse frequency, and a critical frequency of 2000 Hz was identified above which only capacitor discharging could be observed. Correspondingly, the treatments at the critical frequency resulted in the highest internal stress and the lowest corrosion resistance of produced PEO coatings in a simulated body fluid, as evaluated by electrochemical impedance spectroscopy and potentiodynamic polarisation scans. At the same time, the corrosion resistance of Mg was improved, by a factor of >10, by the PEO treatments at a pulse frequency of 3000 Hz, which allowed simultaneous increases in coating thickness, porosity refinement and internal stress relaxation without significant cracking.
合写作者：Allan Matthews, Evgeny Parfenov
第一作者：Yonghao Gao
论文类型：期刊论文
通讯作者：Aleksey Yerokhin
论文编号：WOS:000346182900027
学科门类：工学
一级学科：材料科学与工程
文献类型：J
卷号：149
页面范围：218-230
是否译文：否
发表时间：2014-12-10
收录刊物：SCI、EI