铝阳极氧化膜纳米孔阵列结构的自组织过程分析

提出了在铝阳极氧化膜的生长过程中存在两种力的作用,一种是在阻挡层形成时就已经存在的由于基体铝与氧化铝之间晶格不匹配产生的内应力的作用,另一种是随着纳米孔的形成,存在于纳米孔内壁的表面张力的作用.铝阳极氧化膜纳米孔阵列的自组织过程是在这两种力的共同作用下进行的.这两种力的大小随着纳米孔形貌的变化而改变,当铝阳极氧化膜中的纳米孔呈规则的六角排列时,这两种力达到平衡,此时体系的能量也最低.

The Analysis of Self- organizing Process of Anodic Alumina Films with Nano- pore Array Structure

With the increase of the anodizing ti me,the nanoporous morphology of the anodic porous alumina film formed by anodizing Al in an oxalic acid solution will change from irr egular to regular and the distribution of nanoporous will also change from dis array to regular hexangular array.T he results indicated that there was h igh internal stress in the barrier layer due to the severe mismatch between th e barrier layer formed in early anodi zation and the Al substrate.The release of t he internal stress resulted in the or igination of the numerous nanoporou s in the surface of the barrier layer,which a ccordingly made the surface energy o f oxide film increase quickly.The in ternal stress in the walls and the surface te nsion in the surface of nanoporous acted together in the anodization and d eter-mined the morphology and distributi on of the nanoporous in each phase of t he anodization.When these two forces reached a balance,the nanoporous possessed excellent uniformity in dia meter and spacing of the holes.At thi s time,the energy of the system is at th e lowest.The transition process fro m unbalance to balance of the these tw o forces is the internal drive in the se lf-organized process of the porous c onfiguration from the initial irreg ular through to regular array.