Corrosion behaviour of AM60 magnesium alloys containing Ce or La under thin electrolyte layers. Part 1: Microstructural characterization and electrochemical behaviour

The corrosion behaviour of AM60 containing Ce or La (AMRE1) under thin electrolyte layers (TEL) in 3.5 wt.% NaCl solution was investigated by cathodic polarization and EIS. The results indicated corrosion resistance was enhanced by TEL decrease until 100 μm. There were three kinetic regions in polarization curves of AMRE1, whereas the second region disappeared for AM60. Meanwhile, EIS results showed capacitive loop at LFs for AMRE1 appeared under 200–300 μm thickness. The presence of second regions in polarization curves and capacitive loops at LFs in EIS was attributed to performance of new phases (γ) as indicated in microstructural characterization.