The adhesion of vacuum evaporated and ion plated Cu films on mild steel substrates has been studied. A rod whose bottom was bonded to the film with epoxy adhesive was twisted and stripped off from the substrate. The critical torque was taken a measure of the adhesion. The film deposited by ion plating process provided excellent adhesion to the substrate compared with that deposited by vacuum evaporation. An X-ray photoelectron spectroscopic examination revealed that hydroxide on the top most surface of non-sputtered substrate before deposition was the cause for the poor adhesion of the film to the substrate. The composition profile of the film obtained by using an ion microprobe analyser showed that the ion plated specimen had much broader interface than that of vacuum evaporated one. It was suggested that good adhesion of the ion plated Cu film was attributed to both the sputter-cleaning effect before deposition and the formation of graded interface by ion implantation of high energy particle.

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Stress corrosion cracking tests of commercial structural steel plates (JIS-S53C, 50L×5W×1Tmm) tempered at various temperatures and for different times in the molten salt bath were carried out in the boiling 20w/v% NH₄NO₃ solution. A C-type stress corrosion cracking test apparatus having a final set span of 40mm was employed. On the basis of the results obtained, the influence of the tempering temperature and time on the incubation time, propagation behavior and failure time in stress corrosion cracking were discussed.

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The morphology of the oxide films on aluminum by ac-anodizing at constant voltages in oxalic acid solution with Pt as counter electrode has been studied. The cathodic current during ac-anodizing is considerably higher than the anodic current. The cathodic current to anodic current ratio increases with increasing forming voltage. Electron micrographs of the section of films show distorted pores (sponge like structures). They may be caused by rapid hydrogen evolution at the pore bottoms and/or the barrier layer, associated with high cathodic currents. The distortion of the porous structure increases with increasing voltage. The presence of defects in the barrier layer is also estimated from the measurment of leakage current on ac-films. The cell shape is not clearly hexagonal unlike do-films and cell boundaries are not distinct. The average cell diameter of the ac-films is linear with the forming voltage. The barrier layer thickness measured by Hunter method increases with increasing voltage. The ac-film cell size and barrier layer thickness are close to those for do-films when taking the peak voltage of ac-wave as the forming voltage.

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The influence of temperature on the morphology and structure of the anodic film on zinc electrode in an alkaline zincate solution was studied under galvanostatic conditions. The oxide film was analyzed by means of an electron microscope and X-ray diffraction. Amount of the oxide film increased when the bath temperature was increased higher up to about 45°C and 55°C in the solutions of 2mol/l KOH and 8mol/l KOH, respectively. A silvery film was formed on the anode in the low temperature range while the film color changed golden in the high temperature range. The reaction rate for the film formation increased remarkably in the high temperature range. The film grew up on the (0002) and (1010) planes of zinc oxide. When the bath temperature reached to 55-60°C, the preferred orientations decreased on the zinc crystal planes of (0002), (1010-2), (1120), (1122), and (2021-3). The zinc crystal was composed of (1013-5) planes at 55-60°C. It was considered that the inhibition of passivation phenomenon could be related to the structure of the oxide film formed on zinc.

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