Metallographic preparation of soft and very ductile materials can be challenging, especially when the analysis techniques used require perfection, such as examination using Electron Backscatter Diffraction (EBSD). Following these guidelines will help to ensure that your preparation is both efficient and effective:
- Most problems experienced by users start with poor sectioning. Section the sample as delicately as can be practically achieved. Ideally this would be done with a precision cutter such as the Isomet Cutter range.
- Aggressive sectioning can lead to deformation in ductile materials that is not visible to the eye, but can prevent EBSD or even successful etching
- Mount with a high quality compound that is not excessively hard compared with your sample material
- We would recommend the use of epoxy mounting compounds such as Epoxicure to ensure best results. Add Conductive Filler for SEM/EBSD samples
- Use a finer grit than normal on the grinding stage, but ensure that all cutting damage is removed. Don’t over-use grinding paper!
- Follow a recommended preparation route, paying particular attention to cleanliness and inspecting the sample at each stage
- See www.buehler.com for multiple recommendations on preparation routes for different materials. Diamond paste is often preferable to solutions or sprays for highly ductile materials.
- Add a short vibratory polish to the end of the preparation route.
- Typically 20 to 60 minutes on a VibroMet 2 polisher using a napped cloth such as MasterTex and a high quality polishing compound such as MasterPrep alumina or MasterMet colloidal silica will greatly improve your results
Following these basic guidelines will greatly enhance the quality of any polished sample, improve analysis accuracy and should not take much longer than standard preparation.