Effects of aluminium surface morphology and chemical modification on wettability

Research output: Contribution to journalJournal articleResearchpeer-review

19 Citations (Scopus)

Abstract

Aluminium alloys are some of the predominant metals in industrial applications such as production of heat exchangers, heat pumps. They have high heat conductivity coupled with a low specific weight. In cold working conditions, there is a risk of frost formation on the surface of aluminium in the presence of water vapour, which can lead to the deterioration of equipment performance. This work addresses the methods of surface modification of aluminium and their effect of the underlying surface morphology and wettability, which are the important parameters for frost formation. Three groups of real-life aluminium surfaces of different morphology: unpolished aluminium, polished aluminium, and aluminium foil, were subjected to surface modification procedures which involved the formation of a layer of hydrophilic hyperbranched polyethyleneglycol via in situ polymerization, molecular vapour deposition of a monolayer of fluorinated silane, and a combination of those. The effect of these surface modification techniques on roughness and wettability of the aluminium surfaces was elucidated by ellipsometry, contact angle measurements and atomic force microscopy. We demonstrated that by employing different types of surface modifications the contact angle of water droplets on aluminium samples can be varied from 12° to more than 120°. A crossover from Cassie–Baxter to Wenzel regime upon changing the surface roughness was also observed.
Original languageEnglish
JournalApplied Surface Science
Volume296
Pages (from-to)124-132
ISSN0169-4332
DOIs
Publication statusPublished - 30 Mar 2014

Keywords

  • Surface modification
  • Contact angle
  • Aluminium surface
  • Roughness
  • n situ polymerization
  • Molecular vapour deposition

Fingerprint Dive into the research topics of 'Effects of aluminium surface morphology and chemical modification on wettability'. Together they form a unique fingerprint.

Cite this