Back to Search
Start Over
Influence of Zn and Mg Alloying on the Corrosion Resistance Properties of Al Coating Applied by Arc Thermal Spray Process in Simulated Weather Solution
- Source :
- Acta Metallurgica Sinica (English Letters). 31:591-603
- Publication Year :
- 2018
- Publisher :
- Springer Science and Business Media LLC, 2018.
-
Abstract
- In this study,Al–Zn and Al–Mg coatings were deposited on steel substrates by an arc thermal spray process.X-ray diffraction and scanning electron microscopy were used to characterize the deposited coatings and corrosion products.Open circuit potential(OCP),electrochemical impedance spectroscopy,and potentiodynamic studies were used to assess the corrosion characteristics of these coatings after exposure according to the Society of Automotive Engineers(SAE)J2334 solution of varying durations.This solution simulates an industrial environment and contains chloride and carbonate ions that induce corrosion of the deposited coatings.However,the Al–Mg alloy coating maintained an OCP of approximately-0.911 V versus Ag/Ag Cl in the SAE J2334 solution even after 792 h of exposure.This indicates that it protects the steel sacrificially,whereas the Al–Zn coating provides only barrier-type protection through the deposition of corrosion products.The Al–Mg coating acts as a self-healing coating and provides protection by forming Mg6Al2(OH)16CO3(Al–Mg layered double hydroxides).Mg6Al2(OH)16CO3has interlocking characteristics with a morphology of plate-like nanostructures and an ion-exchange ability that can improve the corrosion resistance properties of the coating.The presence of Zn in the corrosion products of the Al–Zn coating allows dissolution,but,at the same time,Zn5(OH)6(CO3)2and Zn6Al2(OH)16CO3are formed and act to reduce the corrosion rate.
- Subjects :
- Materials science
Scanning electron microscope
020209 energy
Metallurgy
Metals and Alloys
Layered double hydroxides
02 engineering and technology
engineering.material
021001 nanoscience & nanotechnology
Chloride
Industrial and Manufacturing Engineering
Dielectric spectroscopy
Corrosion
Coating
0202 electrical engineering, electronic engineering, information engineering
medicine
engineering
0210 nano-technology
Thermal spraying
Dissolution
medicine.drug
Subjects
Details
- ISSN :
- 21941289 and 10067191
- Volume :
- 31
- Database :
- OpenAIRE
- Journal :
- Acta Metallurgica Sinica (English Letters)
- Accession number :
- edsair.doi...........408a1e40ffa2519c8fff2a4245209f6d