著者
中野 博昭 大上 悟 西野 友朗 福島 久哲 小林 繁夫
出版者
The Mining and Materials Processing Institute of Japan
雑誌
Journal of MMIJ (ISSN:18816118)
巻号頁・発行日
vol.128, no.10_11, pp.590-595, 2012-09-25 (Released:2013-10-28)
参考文献数
15
被引用文献数
3 5

Electrodeposition of Cu was conducted in a synthetic electrorefining solution to investigate the effect of gelatin, thiourea and chloride ions on the polarization curve for Cu deposition, morphology, texture, surface roughness and the throwing power of the deposited Cu. In a solution containing both gelatin and chloride ions, the cathode potential for Cu deposition was significantly polarized at current densities above 200A/m2, while the thiourea depolarized the potential for Cu deposition at 200 to 1000A/m2. In a solution containing the three additives, i.e. gelatin, thiourea and chloride ions, the potential for Cu deposition was polarized at 500A/m2. It is supposed that the synergistic effect of gelatin and chloride ions on the polarization prevailed over the depolarization effect of thiourea. In the Cu deposited at initial stage, the chloride ions promoted the field-oriented texture with the orientation of direction. However, Cu deposited at initial stage from the solution containing gelatin, thiourea and chloride ions was composed of both the inclined texture type and the epitaxial growth type of crystals. The surface roughness and throwing power of the deposited Cu was most improved in the solution containing gelatin, thiourea and chloride ions, showing the synergistic effect of three additives. The thiourea had an effect on decreasing the surface roughness of the deposited Cu, and chloride ions improved the throwing power of Cu.
著者
孫 仁俊 中野 博昭 大上 悟 小林 繁夫 福島 久哲 堀田 善治
出版者
公益社団法人 日本金属学会
雑誌
日本金属学会誌 (ISSN:00214876)
巻号頁・発行日
vol.69, no.10, pp.892-898, 2005 (Released:2005-10-20)
参考文献数
13
被引用文献数
12 13

The effect of equal-channel angular pressing (ECAP) on the pitting corrosion resistance of Al and Al-Mg alloy was investigated by means of polarization curves in solutions containing 300 ppm of Cl- and by surface analysis. The potentials for pitting corrosion of Al and Al-Mg alloy were evidently shifted to the noble direction by ECAP process, indicating that this process improves resistance to pitting corrosion. SEM observation revealed that the pitting corrosion occurred near the impurity precipitates and the size of impurity precipitated decreased with ECAP process. The time-dependence of corrosion potential and the polarization resistance determined by AC impedance technique suggested that the formation rate of Al oxide films was increased with ECAP process. The improvement in pitting corrosion resistance of Al and Al-Mg by ECAP seems to be attributable to the decrease in the size of impurity precipitates and the increase in the formation rate of Al oxide films.