Corrosion resistance of water repellent aluminum surfaces with various wetting morphologies
Abstract
We investigated the improved corrosion resistance of micro/nanostructured aluminum surfaces by varying wetting morphologies. By combining the wet-chemical oxidation schemes and low surface energy coating, we induced three different wetting morphologies including superhydrophilic, Cassie-mode superhydrophobic and Wenzel-mode hydrophobic on micro/nanostructured aluminum surfaces. The superhydrophilic oxide layers provided approximately 30-76% improvement in the corrosion resistance compared to untreated ones. When a hydrophobic coating was added to the oxide layers and Cassie-mode superhydrophobicity was induced, all types of samples showed over 95% increase in the corrosion resistance compared with untreated ones. When the air trapped on the superhydrophobic surfaces was removed in a vacuum environment, the corrosion resistance decreased but still provided 70-98% increase compared with untreated ones. The present work showed that the superhydrophobic treatment is a very effective way to improve the corrosion resistance but the proper choice of the passivation layer and hydrophobic coating can provide a meaningful increase in the corrosion resistance. The present work further clarified the high corrosion resistance of superhydrophobic aluminum surfaces and will help to develop practical anti-corrosion resistance surfaces.
- Publication:
-
Applied Surface Science
- Pub Date:
- February 2019
- DOI:
- 10.1016/j.apsusc.2018.10.218
- Bibcode:
- 2019ApSS..467.1046S
- Keywords:
-
- Corrosion resistance;
- Aluminum corrosion resistance;
- Superhydrophobic aluminum surface;
- Superhydrophilic aluminum surface;
- Hydrophobic aluminum surface;
- Wetting morphologies