Cold rolling is a plastic forming method applied to reach the desired thickness, especially for flat products. Internal stresses occur with deformation in hot rolled coils, in which rolling process is started with a thickness of 3 – 4 mm. With the internal stresses formed, the grains of the materials are elongated in the rolling direction, and changes occur in the crystal structures and phase structures depending on the alloy. The stresses that occur with the deformation make the material embrittle and the materials lose their ability to be shaped. It is annealed to give the materials the ability to be reshaped, to eliminate the changes that occur in the internal structure with deformation, and to make the grains as coaxial as possible by recovering. Especially if the annealing process is carried out in an open atmosphere furnace, that is, a combustion with rich oxygen causes the formation of high temperature oxides on the surface of the material under the exposed annealing conditions. These high temperature oxides cause decreases in corrosion resistance and adversely affects mechanical properties for materials such as stainless steel, where corrosion resistance is sought. Against the aforementioned negativities, there is a need to re-grow a regular passive oxide layer on the surfaces of stainless steels, especially by dissolving the high temperature oxides on the surfaces in acids[1].

In this study, the structures of high temperature oxides growing on the surfaces of AISI 304 and 430 alloy stainless steels annealed at different temperatures and times were characterized and their surface morphologies and growth patterns along the oxide were investigated. Inferences were obtained on how changes in the structure, composition and morphological structure of oxides will affect their ability to dissolve in acids.