Multiscale Wettability of Microtextured Irregular Surfaces

Area of Science:

• Materials Science
• Surface Engineering
• Tribology

Background:

• Surface microgeometry significantly impacts wetting behavior.
• The scale of observation is critical for understanding surface-structure-wettability relationships.
• Electro-discharge machining (EDM) is a key process for creating specific surface topographies.

Purpose of the Study:

• To analyze the correlation between contact angles and surface complexity of AA 6060 after EDM.
• To establish a methodology for selecting optimal observation scales for wetting phenomena on irregular surfaces.
• To identify geometric surface features that govern contact angle and design surface wettability.

Main Methods:

• Focus variation 3D microscopy was used to render and characterize aluminum alloy surfaces.
• Standardized ISO, area-scale, and length-scale parameters were employed for topographic description.
• Contact angle measurements (static and dynamic) were performed to assess wetting behavior.

Main Results:

• The study determined optimal observation scales for analyzing wetting on EDM-processed surfaces.
• Key topographic parameters influencing contact angle were identified.
• It was confirmed that EDM parameters can be used to engineer surface wettability (hydrophilicity/hydrophobicity).

Conclusions:

• Surface wettability can be precisely designed through control of EDM parameters.
• Understanding scale-dependent surface characteristics is crucial for predicting wetting behavior.
• The findings provide a framework for tailoring surface properties for specific applications.