STUDIES ON COMPOSIT PLATING AS A FABRICATING PROCESS FOR FUNCTIONAL THIN FILM

复合镀层使镀层表面具有耐磨、自润滑、耐腐蚀或抗氧化等多种功能特性。虽然复合涂层在许多工业过程中得到了应用，但分散体共沉积的机理尚未完全阐明。在本研究项目中，得到以下结果：首先阐明了氧化颗粒（如二氧化钛颗粒）的共沉积与吸附离子的种类和数量的关系。主要采用含二氧化钛颗粒的酸性硫酸铜浴。二氧化钛颗粒表面OH基团与Cu^<2+>在镀液中反应生成H^+，吸附Cu^<2+>在颗粒上。这个反应取决于Cu^<2+>的浓度和溶液的pH值。研究发现，共沉积二氧化钛的数量随着镀液pH的增加而增加，这表明共沉积颗粒的数量取决于Cu^<2+>在颗粒上的吸附量。讨论了共沉积行为与沉积金属离子性质的关系。

Composite coating gives various functional properties, such as wear resistance, self-lubricating, corrosion or oxidation resistance etc.to the plated surface. Although the composite coatings are used in many industrial processes, the mechanism of codeposition of dispersoid is not fully elucidated.In this research project, the following results were obtained ; At first, the dependence of the codeposition of oxide particles, such as titanium dioxide particles, on the kind and the amount of adsorbed mental ion was elucidated. An acid copper sulfate bath with titanium dioxide particles was mainly used for this investigation. The surface OH group of the titanium dioxide particle reacts with Cu^<2+> in the bath, which results in H^+ production and the adsorption of Cu^<2+> on the particle. This reaction depends both on the concentration of Cu^<2+> and on the pH of the solution. It was found that the amount of codeposited titanium dioxide increased with increasing pH of the bath, which indicates that the amount of codepositing particles depends upon the amount of Cu^<2+> adsorbed on the particle. Relation between the codeposition behavior and the nature of depositing metal ion is also discussed.