Microporous metallic scaffolds supported liquid infused icephobic construction

Phase change surfaces with porous metallic structures for long-term anti/de-icing application

HYPOTHESIS

Ice mitigation has received increasing attention due to the severe safety and economic threats of icing hazards to modern industries. Slippery icephobic surface is a potential ice mitigation approach due to its ultra-low ice adhesion strength, great humidity resistance, and effective delay of ice nucleation. However, this approach currently has limited practical applications because of serious liquid depletion in the icing/de-icing process.

EXPERIMENTS

A new strategy of phase change materials (PCM)-impregnation porous metallic structures (PIPMSs) was proposed to develop phase changeable icephobic surfaces in this study, and aimed to solve the rapid depletion via the phase changeable interfacial interactions.

FINDINGS

Evaluation of surface icephobicity and interfacial analysis proved that the phase changeable surfaces (PIPMSs) worked as an effective and durable icephobic platform by significantly delaying ice nucleation, providing long-term humid tolerance, low ice adhesion strength of as-prepared samples (less than 5 kPa), and signally improved maintaining capacity of impregnated PCMs (less than 10 % depletion) after 50 icing/de-icing cycles. To explore the interfacial responses, phase change models consisting of the unfrozen quasi-liquid layer and solid lubricant layer at the ice/PIPMSs interfaces were established, and the involved icephobic mechanisms of PIPMSs were studied based on the analysis of interfacial interactions.

On the Durability of Icephobic Coatings: A Review

Ice formation and accumulation on surfaces has a negative impact in many different sectors and can even represent a potential danger. In this review, the latest advances and trends in icephobic coatings focusing on the importance of their durability are discussed, in an attempt to pave the roadmap from the lab to engineering applications. An icephobic material is expected to lower the ice adhesion strength, delay freezing time or temperature, promote the bouncing of a supercooled drop at subzero temperatures and/or reduce the ice accretion rate. To better understand what is more important for specific icing conditions, the different types of ice that can be formed in nature are summarized. Similarly, the alternative methods to evaluate the durability are reviewed, as this is key to properly selecting the method and parameters to ensure the coating is durable enough for a given application. Finally, the different types of icephobic surfaces available to date are considered, highlighting the strategies to enhance their durability, as this is the factor limiting the commercial applicability of icephobic coatings.

Interdependence of Surface Roughness on Icephobic Performance: A Review

Ice protection techniques have attracted significant interest, notably in aerospace and wind energy applications. However, the current solutions are mostly costly and inconvenient due to energy-intensive and environmental concerns. One of the appealing strategies is the use of passive icephobicity, in the form of coatings, which is induced by means of several material strategies, such as hydrophobicity, surface texturing, surface elasticity, and the physical infusion of ice-depressing liquids, etc. In this review, surface-roughness-related icephobicity is critically discussed to understand the challenges and the role of roughness, especially on superhydrophobic surfaces. Surface roughness as an intrinsic, independent surface property for anti-icing and de-icing performance is also debated, and their interdependence is explained using the related physical mechanisms and thermodynamics of ice nucleation. Furthermore, the role of surface roughness in the case of elastomeric or low-modulus polymeric coatings, which typically instigate an easy release of ice, is examined. In addition to material-centric approaches, the influence of surface roughness in de-icing evaluation is also explored, and a comparative assessment is conducted to understand the testing sensitivity to various surface characteristics. This review exemplifies that surface roughness plays a crucial role in incorporating and maintaining icephobic performance and is intrinsically interlinked with other surface-induced icephobicity strategies, including superhydrophobicity and elastomeric surfaces. Furthermore, the de-icing evaluation methods also appear to be roughness sensitive in a certain range, indicating a dominant role of mechanically interlocked ice.