In situ surface investigation of austenitic stainless steel in nitric acid medium using electrochemical atomic force microscopy

 Using potentiodynamic polarization and electrochemical atomic force microscope, the surface morphology of austenitic stainless steel has been investigated with the aim of understanding the passive film property in nitric acid medium. It has been found that passive film consists of platelet-like structures with a moiré pattern at lower concentrations (0.1, 0.5 M); at higher concentrations (0.6, 1 M) the platelet-like structures disappear, revealing the grain boundary structure.