Kelvin Microprobe Analytics on Iron-Enriched Corroded Magnesium Surface

authors	Yasakau, KA; Hoche, D; Lamaka, SL; Ferreira, MGS; Zheludkevich, ML
nationality	International
journal	CORROSION
author keywords	atomic force microscopy; commercial purity magnesium; high purity magnesium; iron re-deposition; magnesium corrosion mechanism; scanning Kelvin probe force microscopy; Volta potential difference
keywords	PROBE FORCE MICROSCOPY; ANODIC HYDROGEN EVOLUTION; CORROSION BEHAVIOR; LOCALIZED CORROSION; ALLOYS; METAL; FILM; MG; INHIBITION; POTENTIALS
abstract	This work contributes to the better understanding of Kelvin microprobe response to iron re-deposition related surface morphology changes resulting from Mg corrosion caused by iron-rich impurities. Scanning Kelvin probe force microscopy (SKPFM) was performed on polished Mg samples at well-defined surface conditions occurring from corrosive exposure to 0.05 M NaCl electrolyte or dissolved FeCl2. Volta potential difference was measured and mapped across iron-rich areas, unaffected areas of alpha-Mg, and on FeCl2 exposed areas. Afterward, the obtained potential values were evaluated via the derived mathematical expression, based on model assumptions. Subsequently, they were compared and then correlated to the corrosion process. The article demonstrates what kind of information can be obtained by SKPFM and what conclusion can be drawn toward the detailed explanation of recently reported iron re-deposition mechanism on corroding Mg surface. Finally, suggestions toward the improved application of SKPFM for Mg corrosion are made.
publisher	NATL ASSOC CORROSION ENG
issn	Oct-12
isbn	1938-159X
year published	2017
volume	73
issue	5
beginning page	583
ending page	595
digital object identifier (doi)	10.5006/2260
web of science category	Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering
subject category	Materials Science; Metallurgy & Metallurgical Engineering
unique article identifier	WOS:000403210800001