摘要
研究了铝的阳极氧化膜在SnSO_4和AgNO_3溶液中交流电解着色时,着色剂的浓度和着色电压等因素对正向和反向峰值电流密度随着色时间的变化规律的影响。证实了析氫反应与交流电的交互作用对膜的阻挡层的活化是着色物质在孔底部沉积的必要条件;升高电压有利于加速活化过程和沉积物在孔底形核,但电压超过一定值后沉积物又发生溶解。用缺陷理论解释了阳极氧化膜的整流特性,并进一步阐明了正负半周的离子传输过程。
A modified mechanism of AC electrolytic coloring of anodized aluminium has been proposed by analysing the variation of the peak current densities with coloring time in both positive and negative half cycles at various constant voltages (rms) It has been found that the duration of the conditioning process of the barrier was determinde by the applied vol tage, i.e., the hither the voltage, the shortor the duration, and, the faster the coloring of the anodic film.The evolution of hydrogen at the initial period of AC coloring proress was considered as the reason for the increasement of flaw density within barrier layer and the pH of the solution near pore base, which caused the electrodeposition of coloring material at the base of pores.The posibility of higher flaw density at AC condition than that at DC condition was deduced from the 'steady'peak current density in the current-time transients of AC coloring.It was postulated that the rectification character of the anodic film was related to the flaws and the ions transportation along them. Also the transport and reactions of ions in both cycles were analysed.
出处
《电镀与精饰》
CAS
1991年第6期3-7,共5页
Plating & Finishing
