In order to colore steel sheet coating of polyvinyl chloride containing Al flake powder (Al-PVC), colored acrylic film (Ac) was laminated on the Al-PVC and its effects on the properties of the Al-PVC were studied. Ac laminated was observed to reduce oxidation of Al-PVC and to restrain decreases in molecular weight. For uncolored acrylic films (nAc), deterioration of the underlying PVC layer was more rapid. Steel sheet coated with Ac/Al-PVC was far better than those coated with PVC, nAc/PVC and Ac in salt spray test, adhesion formability test after aging, heat resistance and composite cycle deterioration test. These results suggest that Ac lamination is a useul technique for coloring Al-PVC coated steel sheet.

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Hydrogen overvoltage of Ni-S films containing from 12 to 41wt% sulfur was measured in 9N NaOH at a current density of 40A/dm² over a period of 30 days. Values for films containing 30wt% sulfur or less increased gradually over time to about 220-360mV, but those for films containing 32wt% sulfur or more (amorphous alloy) decreased from 230 to 110-150mV in 3-10 days, remaining constant there after. Such values show an excellent catalytic activity of Ni-S alloy compared with platinum and steel. The sulfur content of films decreased during electrolysis to about 1/3 of the initial value. The lower hydrogen overvoltages obtained for the films with higher sulfur content were due to the formation of a high density and a uniform distributed fine Ni₃S₂ particles from the Ni-S amorphous alloy during electrolysis.

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The effect on the metallurgical structure and wear behavior of Al-Si alloy and steel produced by nitrogen ion implantation and ion beam mixing deposition (simultaneous nitrogen ion implantation and Ti vapor deposition) using an ion beam source were studied. A combination of X-ray diffraction, Auger electron spectroscopy (AES) and X-ray photoelectron spectroscopy (XPS) was used to determine the metallurgical structure and chemical composition, and to investigate. The chemical bonding state of the ion treated surfaces.
X-ray diffraction data showed that TiN films were formed at room temperature by ion beam mixing treatment. It is demonstrated, that a mixing layer was observed between the substrate and TiN film.
AlN was observed when nitrogen ions were implanted in Al-Si alloy. The pin-on disk wear test showed a decrease in the coefficient of friction and an increase in wear resistance for surface treated by both nitrogen ion implantation and ion beam mixing.

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The corrosion rate of steel in aqueous solutions was monitored by measuring the current in a galvanic couple consisting of steel and an other more noble metal using a zero impedance ammeter. Current densities obtained by monitoring were found to have an extremely high correlation with the corrosion rate obtained from weight loss measurement. The error in the values obtained by weight loss measurement was not more than 25%. Thus, the accuracy of galvanic couple monitor differed little from that of other methods such as Tafel extrapolation, polarization resistance or impedance method. It was also possible with this monitor to obtain simultaneously both the average corrosion rate over a long period and the instantaneous corrosion rate at various points of time. In addition, this method satisfies relatively well the various conditions required of this kind of monitor with regard to automation, cost instrument, measurement conditions and so on.

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Chemical etching of copper on a laminated plate was attained by a novel reagent consisting of DMSO and active halocarbon compounds including carbon tetrachloride or methyl trichloroacetate. The reagent is (1) non-corrosive and reacts selectively with copper, (2) non-aqueous, allowing the use of new resist materials, and (3) easy to prepare, handle and rinse.

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A resin replication technique is proposed for making SEM observations of progressive pits produced during etching in the subsurface of aluminum. This technique reproduces pit morphology more exactly than the conventional anodic replica work.

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