Modeling and kinetic Monte Carlo simulations of the metallographic etching process of second-phase particles

Abstract

Kinetic Monte Carlo simulations of the chemical and electrolytic etching processes of nano-scale particles in two-phase materials were performed. Etching produces a surface relief, which can subsequently be studied by optical, scanning electron and atomic force microscopy to obtain quantitative information on the size, shape and spatial arrangement of the particles. The present simulations yield insight into the dependence of the etched relief on the strengths of the atomic bonds in the two phases and on the shape of the particles. Lower limits for the difference in bond energies necessary (i) to reveal the particles and (ii) to avoid over-etching are established. The results of the simulations are discussed with reference to own actual etching experiments performed for nano-scale precipitates.

Keywords:

• chemical etching
• electrolytic etching
• metallography
• Monte Carlo simulation
• nano-particles
• precipitates
• high-resolution imaging
• atomic force microscopy
• transmission electron microscopy
• scanning electron microscopy
• phase transformations

Acknowledgements

The authors are highly indebted to Dr. S. Divinskiy, Münster, and Dr. D. Rönnpagel, Templin, for discussions, to Dr. J. Pesicka, Prague, for taking the TEM images, and to Prof. Dr. L. Chi, Münster, for making her AFM available to them. Financial support by the Deutsche Forschungsgemeinschaft under the contract No. RE 782/12-1 is gratefully acknowledged.