ONE OF THE MOST interesting and instructive uses of the electron diffraction and electron microscope methods has been the study of the nature of the protective or non-protective corrosion films on metals and alloys. The use of such refined methods is due to the fact that in the protective range the corrosion films are of the order of 10 to 10,000 angstroms in thickness. The study of the crystal structure, crystal size and secondary structure of films in this thickness range can be made only by the use of the electron diffraction method and by electron microscopy. Thicker films can be studied by the use of X-ray diffraction methods and the light microscope.
The reaction involved in the dry oxidation of metals and alloys from a chemical point of view is simpler than many other corrosion reactions. However, from an experimental point of view it may be more difficult. This...
