温控加热下低表面能铝氧化膜的制备及其耐腐蚀初步研究

在氧化铝表面添加有机镀层可以降低其表面能，然而有机镀层具有附着力低、不稳定及污染环境等缺陷。PAOF（多孔氧化铝薄膜）在仿生学上具有类似自然界低表面能生物的表面微结构，为达到进一步提高其表面接触角目的，本研究采用加热冷却等对其进行处理。通过SEM观察，制得的低表面能材料具有约176 nm孔径的规则光滑多孔结构。表面元素分析表明加热处理后和处理前的表面具有一致的化学组成。推断是加热冷却过程使阳极氧化生成的铝氢氧化物和水合物复合结构发生失水，从而露出基底部规则的多孔结构。根据计算，当多孔表面的孔径约为176 nm时，孔中的水滴表面张力和孔隙大气压力将和水滴重力形成力学平衡。电化学实验结果表明，低表面能多孔氧化铝比普通氧化铝具有更低的腐蚀电流。

Preparation of low surface energy aluminum oxide film under temperature-controlled heating and its corrosion protection

The wettability of alumina can be considerably increased by adding organic coatings. However, the organic coating has several disadvantages, such as unstable adhesion and environmental pollution. The surface morphology of PAOF is similar to that of some low wettability surfaces in the natural world. In this research, the wettability of PAOF can be further reduced by heating and cooling. In SEM observation, the surface of low wettability specimens exhibited a regular porous structure with a diameter of 176 nm. Through surface elemental analysis, the surface has a similar chemical composition before and after heat treatment. The heating and cooling process causes anodic oxidation of aluminum hydroxide and loss of water from the hydrate of the composite structure, exposing the basic porous structure. According to the calculation, when the diameter of the porous surface is approximately 176 nm, the water surface tension and pore air pressure in the hole balance the gravity of the water droplet. The electrochemical experiment showed that low wettability alumina has a lower current compared to normal alumina.