Abstract
La conversion coatings in various growth stages were obtained by immersing hot-dip galvanized (HDG) sheets in the lanthanum nitrate solution for different times from 10s to 240min. A growth process model of the La conversion coating on hot-dip galvanized steel was suggested. It is shown that the conversion coating grows more quickly by the zinc grain boundaries, where the cracks occur first and develop gradually on the whole surface of the conversion coating. When the immersion time is increased (more than 60min), some rod-like precipitations containing more Zn and less La are deposited on the conversion coating. Potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) measurement results reveal that, with increasing immersion time, the protective property of the La conversion coatings is gradually increased in the early growth stage and then decreased when the cracks develop.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
