Reaction of oxygen with a clean metal surface follows the sequence (1) adsorption, (2) formation of oxide nuclei, (3) growth of continuous oxide. For stage (1) physical adsorption of O₂ is followed by chemisorption of atomic O. Low energy electron diffraction data show that for Ni a specific number of metal atoms move into the plane of adsorbed O atoms, forming a stable structure which remains on the surface even after heating Ni to near the melting point. The stable chemisorbed atomic O layer together with an overlying chemisorbed O₂ layer are considered to make up the passive film, accounting for the corrosion resistance of many passive transistion metals including Ni, Fe, Cr, Ti and the stainless steels. The adsorbed film functions not as a diffusion barrier, but increases instead the activation energy for hydration and dissolution of the metal lattice by displacing adsorbed H₂O and anions.
On continued exposure to low pressure oxygen, oxide nuclei grow rapidly to a thickness limited by the electron tunneling distance. Thereafter, electron transfer at the metal-oxide interface assumes control of oxide thickness, accounting for predominant lateral growth of nuclei until the film becomes continuous. Growth of the continuous film follows logarithmic oxidation kinetics, with a constant density nagative space charge in the oxide progressively slowing down electron transfer at the metal-oxide interface. At a critical thickness of oxide, trapped charge dissociates, resulting in a diffuse space charge and increase of oxidation rate, leading to two-stage logarithmic behavior.
The stable chemisorbed oxygen-metal atom monolayer probably persists during growth of continuous oxide, the work function of which, rather than of clean metal, determining electron transfer and oxidation rates. Hence the (111) surface of Ni on which O is adsorbed has the highest work function and is also the face which oxidizes least.

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In three kinds of soils, namely, loam, silt and clay, the relations between moisture content, specific resistance and the corrosivity of soil have been studied. Also, the corrosion rates of steel and ductile cast iron buried in those soils have been determined. The results obtained show that the corrosion rate of steel in soil is slightly smaller than that of ductile cast iron and the former has a maximum at a certain moisture content of soil.

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Ordinary field corrosion tests were carried out on bullets of brass containing 66.97% Cu-32.67% Zn and 63.71% Cu-36.24% Zn fired from a pistol in two natural forests far from human dwelling in the Kirin Province, China. The type of tests was atmospheric and soil exposure. The number of bullets was 480 in all. Stress corrosion cracking in bullets began to start in both atmosphere and soil in 6 months, and all bullets tested were failed by stress corrosion cracking in 27 months.

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Ordinary field corrosion tests in atmosphere and soil were carried out on brass, electrodeposited nickel and mild steel for the purpose of comparison of corrosivity at Kirin Province corrosion-testing station, China, and that at Horomi Pass near Sapporo, Japan. The results were as follows:
(1) The corrosivity in respect of brass was 2 to 3 times higher at Horomi Pass than at the Chinese station.
(2) The corrosivity in respect of electrodeposited nickel was a little higher at Horomi Pass than the Chinese station.
(3) The corrosivity in respect of mild steel was much higher at Horomi Pass than at the Chinese station.

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