Tinplate on silicon killed steel continuously cast and box-annealed, has a high ATC value. Furthermore, the experiment using X-ray photoelectron spectroscopy (XPS) indicates: 1) Silicon oxide layer exists on the steel surface after box annealing; 2) The silicon oxide layer is formed by deposition of silicon during the cleaning process prior to the annealing, and by selective oxidation of the silicon as a steel composition; 3) Most of the silicon oxide can not be removed during pretreatment in the electrolytic tinning process and remains between the steel surface and the alloy layer of the tinplate. The effect of the silicon oxide on the corrosion resistance of the alloy surface has been investigated. As for the flowmelting process, experimental results suggest that, in the early stage of the alloy growth, the silicon oxide prevents the nucleation and the growth of Fe-Sn alloy, but in the succeeding stage, area of the steel exposed to free tin accellates alloy growth, because Fe atoms diffuse from between alloy crystallites. Also in this stage, the alloy continuity on the steel surface is little improved because the growth is mainly vertical to the steel surface. This is the reason for the high ATC value. ATC value decreases to 1/2-1/3 by heating, but corrosion current density on the alloy surface shifts slightly. More investigation is necessary to clear up the reason for the decrease in ATC value by heating.

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The copper films of 6-10μm in thickness were ion plated on steel substrates under various process conditions using a diode system which employs the electric resistance melting of source materials. The ion plated copper films were found to contain considerable amounts of preffered orientation Cu plane (111) by biasing the substrate negatively. The grain size also decreased with increasing the substrate negative bias voltage up to 2kV. Scanning electron microscopy showed that in the ion plated copper films zone-boundary temperatures T₁ and T₂ were shifted to lower values as compared with those of Movchan and Demchishin model in a vacuum evaporation. It was suggested that an ion bombardment under the ion plating affected the crystallographic orientation and the structure of the copper films.

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Anodic polarization measurements as well as surface observations have been carried out on Al-Cu, Al-Mn and Al-Mn-Zn alloy both in NaCl and in AlCl₃ solution to examine the meaning of pitting potential, Ep, and particularly, of repassivation potential, Erep, in NaCl solution. In NaCl solution, remarkable difference between Ep and Erep value was obtained both on Al-Cu alloy and on Al-Mn alloy, while no noticeable difference was observed in Al-Mn-Zn alloy. In AlCl₃ solution, on the other hand, Ep was nearly equal to Erep on all the materials examians examined. Ep just coincided with the critical potentical of facet-pit formatin on the former two materials, while relatively uniform type of dissolution was observed even in the potential region more noble than Ep on Al-Mn-Zn alloy. The relationships between Ep and Erep values in NaCl solution were discussed in terms of the extent of local salt concentration within the pit.

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