Corrosion inhibition for aluminum (99.8%) in a neutral aqueous solution, H₂O/ethylene glycol/ammonium adipate, with various surfactants at high temperatures has been investigated. The inhibition efficiency of the additives was evaluated from H₂ gas volume evolved during the corrosion test. The polarization resistance measurement and the analysis of the Tafel slopes with computer were also made to study the electrochemical parameters and to estimate the corrosion rate. The most promising inhibitor was polyoxyethylene sorbitan (five-membered ring) monooleate (S-O). The addition of 1 wt% S-O showed perfect corrosion inhibition in a wide temperature range. Sorbitol and gelatin were also good inhibitor. The corrosion rate for S-O was estimated to be one thousandth of it without additive and one twentieth of sorbitol. Moreover, it was found that the rest potential shifted to more noble, the polarization resistance became larger, and the Tafel slopes became smaller when the inhibition of the additive was more effective.

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The anodic behavior of copper electrodeposits from an acid copper sulfate bath containing sparingly soluble organic sulfur compounds has been studied. The solubilities of 2-mercaptobenzothiazole (MBT) and 2-(N, N-diethylthiocarbamoylthio) benzothiazole (DECB) were 27 and 5mg/l respectively in the acid copper sulfate bath (CuSO₄ 1mol/l, H₂SO₄ 0.5mol/l) at 30°C. The concentrations of these compounds during electrolysis were maintained in nearly saturated values in the presence of the excess solid compounds. At the current density of 2A/dm², the electrodeposit contained 0.055% S and 0.061% C for the bath with MBT, whereas 0.010% S and 0.008% C for the bath with DECB. During galvanostatic electrolysis in the stagnant condition, the growth of nonconducting film formed on the anode, caused a marked rise in the anode potential. The film, however, could be easily wiped off under mild agitation and the anode potential was kept in less noble one with slight oscillation. The amount of anode slime was small as in the case of phosphorized copper anode.

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Solar selective black Cr-Co alloy coatings have been prepared from the tri-valent chromiumformate/acetate or -oxalate baths containing a small amount of cobalt chloride. The black Cr-Co alloy coating electrodeposited with a plating time of about 1min and at current densities from 15 to 50 Adm^-2 from the formate bath and that obtained at current densities from 30 to 50 Adm^-2 from the oxalate bath have a solar absorptance of 0.92-0.96 and thermal emittance of 0.10. The alloy coatings thus prepared also have excellent thermal stability. ESCA study reveals that the Cr and Co in the alloy coatings exsist as oxides. The bath composition, especially its Co content, seems to affect the composition, thickness and therefore the optical characteristics of the alloy coatings.

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The effect of heat treatment on the magnetic properties and structure of electroless Co-P plating films was investigated. The results obtained are as follows. 1) The four types of electroless cobalt solutions were employed as the plating baths. The deposition rate of these baths was affected by bath pH and phosphorus content in deposited films varied in the range of 0.8-4.3%. 2) The coercive force of deposited films varied wide range from 1000A/m (13Oe) to 70000A/m (880 Oe) at 0.10μm film thickness and these films were classified into three groups according to their coercive force. And these properties changed characteristically with heat treatment. 3) The structure of deposited films which varied widely from amorphous to crystal was changed remarkably by heat treatment. X-ray method revealed that Co₂P precipitates at 773K-873K and TEM observation showed that the grain size of films changes with heat treatment. 4) It was revealed by this investigation that the magnetic properties of electroless Co-P plating films and their change with heat treatment are dominated mainly by grain size of films.

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