Correlative characterization of Zn-Al-Mg coatings by electron microscopy and FIB tomography
Tia Truglas, Jiri Duchoslav, Christian K. Riener, Martin Arndt, C. Commenda, David Stifter, Gerhard Angeli, Heiko Groiß
Abstract
The microstructure of a hot-dip Zn-Al-Mg anti-corrosion coating on steel was investigated upon quenching during solidification. As expected, at least two different eutectic microstructures were generated and subsequently characterized using scanning and transmission electron microscopy, elemental analysis, and selected area diffraction. The difference was found in the eutectic intermetallic MgZn phase, which was identified as MgZn2 and Mg2Zn11, respectively. Based on the experimental results, we developed an image processing algorithm for electron micrographs, which automatically detects the altered eutectic microstructure. Furthermore, a 3D focused ion beam tomography was performed for an in-depth analysis of the phase morphologies at the interface between the different eutectic structures.