For the purpose of improving corrosibility of the tin-plate of containers for acidic foods, a study to explain tin-plate corrosion mechanism was carried out.
From electrochemical point of view, the present authors classified the stage of corrosion into the two: the first period when coated tin still covers steel base completely, and the second period when the base steel is partly exposed and the alloy layer begins to be affected. As the results of these experiments, it has been clarified that tin acts as complete protective metal in a can on account of its high hydrogen over-voltage, and even in case steel is exposed, the corrosion of steel base does not take place remarkably, because iron electrode potential becomes nobler than that of tin contrary to the usual ionization tendency. This is primarily due to the fact that the surface of tin becomes little dissociating compound in organic acids.
The electrode potential of tin-iron alloy, however, is the noblest of these three layers and in most stable state, but as steel dissolves in steel and alloy couple, the problems hereafter concerning the alloy layer will be the thickness of tin coating and the cracks or exposed portion of steel, etc.

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It is a well-known fact that aluminum is an amphoteric compound and is corroded by acid and alkali. In the present study, small quantities of oxidizing agent and reducing agent were added to acid and alkali and their effects on corrosion were examined.
For the experiments, HCl, H₂SO₄ and HNO₃ were used as acids, NaOH as alkali, KMnO₄ and K₂Cr₂O₇ as oxidizing agents, and SnCl₂ and NaHSO₃ as reducing agents.
The result revealed that corrosion was most active when SnCl₂ was used, and was next active in the cases of KMnO₄ and K₂Cr₂O₇.
From the above fact, it has become known that coexistence of heavy metal ions, no matter whether they are oxidizing agents or reducing agents, accelerates corrosion.
Similar experiments were carried out on duralumin.

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