TEM Examination of the Film Formed on Corroding Mg Prior to Breakdown

The composition and structure of the film formed on Mg corroding in 0.01 M NaCl prior to any visible localized breakdown event was examined using a transmission electron microscopy (TEM). Focused ion beam (FIB) milling was used to prepare electron transparent lamellae of the film in cross-section. The TEM examination revealed that the film was comprised chiefly of a magnesium oxide (MgO) region adjacent to the Mg-film interface and a more …