Open AccessDrying Effects on Corrosion Properties of Cr(VI)- and Cr(III)- Treated Electrogalvanized Steel
Author(s) -
Xiaolong Zhang,
Chris van den Bos,
Wim G. Sloof,
A. Hovestad,
Herman Terryn,
J.H.W. de Wit
Publication year - 2006
Publication title -
ecs transactions
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.235
H-Index - 52
eISSN - 1938-6737
pISSN - 1938-5862
DOI - 10.1149/1.2215586
Subject(s) - corrosion , chromium , galvanization , x ray photoelectron spectroscopy , materials science , dielectric spectroscopy , metallurgy , coating , electrochemistry , layer (electronics) , dehydration , high temperature corrosion , nuclear chemistry , chemistry , chemical engineering , composite material , electrode , biochemistry , engineering
Drying effects on corrosion performance of Cr(VI)- and Cr(III)-treated electro-galvanized steel have been studied in NaCl solution using potentiodynamic measurements and electrochemical impedance spectroscopy (EIS). The Cr(VI) and the Cr(III) treated specimens were dried at three different temperatures: 60, 110 and 210°C. The surface layers were investigated using SEM, AES and XPS. The results show that the drying temperature not only affects the morphology of the surface layer, but also changes the chromium oxidation states in the layer. The corrosion protection given to the EG steel by Cr(VI) and Cr(III) pretreatments can be severely reduced if the pretreated surfaces are heated above 110°C. Both types of coating undergo some dehydration during heat treatments, which is undesirable for good corrosion protection. For Cr(VI) coatings, additional degradation mechanisms include widening of the cracks in the coating, and reduction of Cr(VI) to the Cr(III) oxidation state
Accelerating Research
Robert Robinson Avenue,
Oxford Science Park, Oxford
OX4 4GP, United Kingdom
Address
John Eccles HouseRobert Robinson Avenue,
Oxford Science Park, Oxford
OX4 4GP, United Kingdom