Corrosion studies often leave a gap between electrochemical or accelerated tests and natural exposure. This is due to the complexity of the passivation and dissolution processes that occur at the surface of metallic coatings.
To assess this issue, an everincreasing number of experiments are required to study the surrounding electrolyte’s sensitivity to various parameters, such as composition and pH.
New electrochemical tool
In close collaboration with the Max-Planck-Institut für Eisenforschung, OCAS launched a PhD project to develop a new tool that allows high-throughput screening of corrosion properties to identify key parameters adjusted to real-life exposure conditions. As a result, a scanning flow micro-cell – including a dynamic electrolyte renewal system – has been built that addresses all issues. Its main features are:
• Fully computer-controlled high-throughput experimentation
• High lateral resolution obtained by confining the measurement locally
• Electrolyte flow that allows stabilisation of experimental parameters
This high-throughput approach enables us to either vary the measurement parameter on a homogeneous substrate or to perform electrochemical screening along a heterogeneous substrate.
First, the new set-up was fine-tuned to allow semi-automatic parameter screening of zinc dissolution in variable corrosion conditions. Meanwhile, further automation has been implemented and reproducibility has been improved. The analytics of the micro-cell set-up have also been extended to enable the detection of other elements in addition to zinc.
“With coatings becoming more complex in their corrosion protection mechanism, this scanning flow micro-cell will give a real boost to study fundamental corrosion reactions.”