Relations between sample preparation and SKPFM Volta potential maps on an EN AW-6005 aluminium alloy

Quantitative measurements of the chemical composition and the local Volta potential contrast on metal surfaces can be performed with sub-micrometer resolution using a combination of scanning electron microscopy (SEM) and scanning kelvin probe force microscopy (SKPFM). Sample preparation techniques based on metal removal by mechanical and electrochemical polishing, OPS and ion-sputtering, may distort the local chemical composition or microstructure on the surface. Surfaces with insignificant mechanical and chemical distortions can be produced by ultramicrotomy. Ultramicrotomy gives quantitatively reliable SEM and SKPFM results when applied on extruded samples of an EN AW-6005 aluminium alloy.