3D interfacial visualization of ice on solid substrates: unveiling microinterlocking ice

Area of Science:

• Materials Science
• Surface Science
• Physics

Background:

• Mechanical interlocking of ice within surface roughness is key to ice adhesion.
• Previous 2D or destructive methods limited understanding of the ice-solid interface.
• The hidden interfacial region has remained largely hypothetical.

Purpose of the Study:

• To test the hypothesis that in situ freezing X-ray computed tomography (XCT) can non-destructively resolve the 3D ice-solid interface.
• To gain insight into ice mechanical interlocking at the interface.
• To link interfacial morphology to icing behavior.

Main Methods:

• Utilized in situ freezing X-ray computed tomography (XCT) with a 1.6 μm voxel size.
• Analyzed ice droplets on hydrophilic, femtosecond-laser-textured aluminum substrates (Wenzel state).
• Coupled XCT with wetting, ice adhesion, and confocal profilometry measurements.

Main Results:

• Successfully resolved the 3D structure of ice infiltrated and anchored within microgrooves.
• Demonstrated that interlocked ice volume correlates with functional (volume) roughness parameters.
• Showed conventional height-based roughness parameters (Sa, Ra, Sq, Rq) are insensitive to ice interlocking.

Conclusions:

• In situ freezing XCT provides non-destructive 3D visualization of the ice-solid interface.
• Ice interlocking within surface features significantly influences ice adhesion.
• Functional roughness parameters are more relevant than height-based parameters for predicting ice adhesion.