In 2024, the use of CrVI substances will be forbidden by the Reach Regulation. Many studies have been focused on the development of alternative solutions to CAA or conversion coatings. These studies have led to the development of new protective layers (e.g. SAA, TSA, CrIII-based conversions coatings...). But few were dedicated to the development of processes required to remove these new oxide layers. Indeed, current processes use CrVI-based components (phosphochromic etching) and the proposed current alternative (NaOH) can lead to substrate etching if not stopped on time. The aim of this study is then to develop a Cr free solution to remove anodic oxidation layers obtained with new alternative treatments, without deteriorating the aluminium alloy substrate. Please refer to the full topic descriptions document published in this call.