Conductive and Edge Retaining Embedding Compounds: Influence of Graphite Content in Compounds on Specimen’s SEM and EBSD Performance

Abstract

Abstract Since marginal sharpness is often an issue in metallographic samples preparation, various mounting compounds are commercially available which address these issues. Nevertheless, the conductivity of such products is not sufficient for electron backscatter diffraction measurements (EBSD) and products which are electrically conductive often result in a lack of marginal sharpness. Therefore, this study is focussed on the modification of commercially available embedding compounds (epoxy based and phenolic based hot embedding compounds) with graphite to increase their electrical conductivity. To verify the applicability of the modified embedding compounds, the austenitic steel grade 1.4301 was chosen for investigation via scanning electron microscopy and EBSD. Results indicate a good performance during SEM-investigations of the epoxy-based resins, even at 0 wt.-% graphite contents, whereas the phenolic resin-based embedding compound is only applicable for SEM-investigation > wt.-5 % of graphite. Best performance at EBSD measurements were achieved with phenolic resin based hot mounting compounds with glass fibres and an addition > 10 wt.-% graphite.