The decapitation, in some cases also called activation or neutralization, serves primarily to remove a light oxide skin, which can arise through chemical pre-treatment and rinsing processes. Here the decapitation can be an acid, such as hydrochloric acid, sulphuric acid, methanesulphonic acid or a dry acid, or an alkaline, here mostly cyanidic solution. In contrast to pickling, decapitations are only low concentrated with approx. 5% and do not attack the base material or only minimally. The choice of decapitation solution depends on the substrate and the subsequent process.
In addition to the removal of oxide layers, the decapitation serves to neutralise, for example, degreasing solutions which cannot be removed by rinsing due to their soapy character.
After decapering, rinsing is possible, but not mandatory.