Microstructure-Enhanced Omniphobic Interfaces for Robust Anti-Fouling and Anti-Corrosion Performance in Additively...

Area of Science:

• Materials Science
• Surface Engineering
• Additive Manufacturing

Background:

• Metallic heat exchangers face corrosion and fouling in saline/corrosive environments.
• Additive manufacturing (AM) of aluminum offers complex geometries but suffers from surface roughness and reactivity.
• Existing coatings are not optimized for AM-specific surfaces.

Purpose of the Study:

• To develop a durable, multifunctional surface coating tailored for additively manufactured aluminum (AM-Al).
• To enhance the corrosion and fouling resistance of AM-Al components for thermal management systems.

Main Methods:

• Integrated intrinsic microstructures of AM AlSi10Mg with a slippery omniphobic covalently attached liquid (SOCAL) coating.
• Utilized sol-gel chemistry for strong Si-O linkages and mechanical interlocking for adhesion.
• Performed nanoindentation, static corrosion rate tests, and dynamic fouling tests.

Main Results:

• The microstructure-SOCAL hybrid surface demonstrated synergistic chemical-mechanical adhesion with no debonding.
• Achieved a 92% reduction in static corrosion rates and a 90% improvement in antifouling.
• Maintained a foulant-free state for 7 days under dynamic flow, outperforming superhydrophobic (SHP) and SLIPS coatings.

Conclusions:

• Established a new AM-specific coating paradigm using SOCAL for enhanced durability and functionality.
• The approach is adaptable to various AM metals for demanding thermal applications.
• Significantly improved the long-term performance of AM components in corrosive environments.