Electropolishing for TEM Sample Preparation
- Practical Electron Microscopy and Database -
- An Online Book -





Electropolishing is a well-known technique, mostly used to prepare (inter)metallic samples, because these materials are conducting, too soft for crushing, and easily damaged by conventional ion milling.

For instance, 3-mm discs in diameter were punched from alloy sheets of Al-1.5wt% Cu-4.0wt% Mg-0.5wt% Ag and then electropolished in a 1:2 nitric acid:methanol solution (by volume) with applied voltages between 12 and 14V at a temperature of 253K [1].

However, electropolished specimen can be contaminated by residues from either the electrolyte used for thinning or the solvents used for cleaning.





[1] Harsh Deep Chopra, The structure of primary strengthening precipitates in an Al-1.5wt% Cu-4.0wt% Mg-0.5wt% Ag alloy, Philosophical Magazine Letters, 73:6, 351-358 (1996).