Oxide Scale Formation of EN 1.4622 and EN 1.4828 Stainless Steels during Annealing and Descaling Behavior in Neutral Electrolytic Pickling

Oxide scale formation during short-term annealing and electrolytic pickling behavior of ferritic EN 1.4622 austenitic 1.4828 stainless steels are investigated. The is performed at temperatures between 1000 1100 °C for 1200 steel grade under humid atmospheres in simulated industrial process. Neutral pickling, also referred to as neutral electrochemical or the Ruthner Neolyte Process, Na2SO4 electrolyte, efficiency evaluated visually by image analysis pickled surfaces. results show that conditions have a more impactful effect on structure composition resulting oxide within studied condition range. thicknesses scales mainly less than 0.4 μm, while almost all thicker it. In addition, amount silicon inside matrix grades highly different. Longer exposure times higher promote growth annealing, inefficient grade. For grade, surfaces still covered with after pickling.