J4 ›› 2011, Vol. 8 ›› Issue (4): 369-374.doi: 10.1016/S1672-6529(11)60042-5
Superhydrophobicity of Bionic Alumina Surfaces Fabricated by Hard Anodizing
Jing Li1,2, Feng Du3, Xianli Liu1, Zhonghao Jiang4, Luquan Ren1
- 1. Key Laboratory of Bionic Engineering (Ministry of Education, China), Jilin University, Changchun 130022, P. R. China
2. College of Mechanical and Electric Engineering, Changchun University of Science and Technology,
Changchun 130022, P. R. China
3. Armor Technique Institute of PLA, Changchun 130017, P. R. China
4. Key Lab of Automobile Materials (Ministry of Education, China), Jilin University, Changchun 130022, P. R. China
Superhydrophobicity of Bionic Alumina Surfaces Fabricated by Hard Anodizing
Jing Li1,2, Feng Du3, Xianli Liu1, Zhonghao Jiang4, Luquan Ren1
- 1. Key Laboratory of Bionic Engineering (Ministry of Education, China), Jilin University, Changchun 130022, P. R. China
2. College of Mechanical and Electric Engineering, Changchun University of Science and Technology,
Changchun 130022, P. R. China
3. Armor Technique Institute of PLA, Changchun 130017, P. R. China
4. Key Lab of Automobile Materials (Ministry of Education, China), Jilin University, Changchun 130022, P. R. China
摘要：
Bionic alumina samples were fabricated on convex dome type aluminum alloy substrate using hard anodizing technique. The convex domes on the bionic sample were fabricated by compression molding under a compressive stress of 92.5 MPa. The water contact angles of the as-anodized bionic samples were measured using a contact angle meter (JC2000A) with the 3 µL water drop at room temperature. The measurement of the wetting property showed that the water contact angle of the unmodified as-anodized bionic alumina samples increases from 90? to 137? with the anodizing time. The increase in water contract angle with anodizing time arises from the gradual formation of hierarchical structure or composite structure. The structure is composed of the micro-scaled alumina columns and pores. The height of columns and the depth of pores depend on the anodizing time. The water contact angle increases significantly from 96? to 152? when the samples were modified with self-assembled monolayer of octadecanethiol (ODT), showing a change in the wettability from hydrophobicity to super-hydrophobicity. This improvement in the wetting property is attributed to the decrease in the surface energy caused by the chemical modification.