3262.     STANLEY, J. K., HOENE, J. V., AND HUNTOON, R. T.  Oxidation of Pure Iron.  Trans. Am. Soc. Metals, No. 5, 1950, 21 pp.; Chem. Abs., vol. 44, 1950, p. 9886.

        Oxidation of high purity electrolytic Fe (Puron) in air 500°-900° proceeds by the common parabolic rate law, W²=Kt+C.  The oxidation process as a function of temperature follows the usual exponential law.  The rate constant, K, shows the temperature dependence K=0.37e^-33,000/RT.   A Geiger counter X-ray spectrometer showed only 1 oxide, Fe₃O₄, at 500°, but 3 oxides, a-Fe₂O₃, Fe₂O₄, and FeO, at the higher temperatures; metallographic examination resolved the various oxide strata.  FeO could be cooled to room temperature without decomposition to Fe and Fe₃O₄.  Photomicrographs show typical structures.

        STARKWEATHER, H. W.  See abs. 3331.