Mechanically robust superhydrophobic coating for aeronautical composite against ice accretion and ice adhesion

Weather hazards, in particular icing conditions, are an important contributing factor in aviation accidents and incidents worldwide. Many different anti-icing strategies are currently being explored to find suitable long-lasting solutions, such as surface engineering, which can contribute to reduce ice accumulation. Quasicrystals (QCs) are metallic materials, but with similar properties to those of ceramic materials, such as low thermal and electrical conductivities, and high hardness. In particular, QCs that have low surface energy are commercially used as coatings to replace polytetrafluoroethylene (PTFE), also known as Teflon, on frying pans, as they do not scratch easily. PTFE exhibits excellent anti-wetting and anti-icing properties and therefore QCs appear as good candidates to be employed as ice-phobic coatings. Al-based QCs have been applied by High Velocity Oxyfuel (HVOF) thermal spray on typically used aeronautic materials, such as Ti and Al alloys, as well as steels. The coatings have been characterized and evaluated, including the measurement of hardness, roughness, wetting properties, ice accretion behavior in an icing wind tunnel (IWT), and ice adhesion by a double lap shear test. The coatings were studied, both as-deposited, as well as after grinding, in order to study the effect of the surface roughness and morphology on the ice accretion and adhesion properties. The QC coating was compared with PTFE and two polyurethane (PU)-based commercial paints, one of them known to have anti-icing properties, and the results indicate an ice accretion reduction relative to these two materials, and ice adhesion lower than bare AA6061-T6, or the PU paint in the ground version of one of the two QCs. Since the QC coatings are hard (GPa Vickers hardness > 5), a durable behavior is expected.

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Novel Superhydrophobic Surface with Solar-Absorptive Material for Improved De-Icing Performance

Materials ◽

10.3390/ma12172758 ◽

2019 ◽

Vol 12 (17) ◽

pp. 2758 ◽

Cited By ~ 4

Author(s):

Joseph Gonzales ◽

Daiki Kurihara ◽

Tetsuro Maeda ◽

Masafumi Yamazaki ◽

Takahito Saruhashi ◽

...

Keyword(s):

Solar Radiation ◽

Power Consumption ◽

Superhydrophobic Surface ◽

Radiation Absorption ◽

Melting Time ◽

Ice Accretion ◽

Superhydrophobic Coating ◽

Heating Source ◽

Consumption Reduction ◽

Ice Conditions

Ice accretion is detrimental to numerous industries, including infrastructure, power generation, and aviation applications. Currently, some of the leading de-icing technologies utilize a heating source coupled with a superhydrophobic surface. This superhydrophobic surface reduces the power consumption by the heating element. Further power consumption reduction in these systems can be achieved through an increase in passive heat generation through absorption of solar radiation. In this work, a superhydrophobic surface with increased solar radiation absorption is proposed and characterized. An existing icephobic surface based on a polytetrafluoroethylene (PTFE) microstructure was modified through the addition of graphite microparticles. The proposed surface maintains hydrophobic performance nearly identical to the original superhydrophobic coating as demonstrated by contact and roll-off angles within 2.5% of the original. The proposed graphite coating also has an absorptivity coefficient under exposure to solar radiation 35% greater than typical PTFE-based coatings. The proposed coating was subsequently tested in an icing wind tunnel, and showed an 8.5% and 50% decrease in melting time for rime and glaze ice conditions, respectively.

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Design of Icephobic Surfaces by Lowering Ice Adhesion Strength: A Mini Review

Coatings ◽

10.3390/coatings11111343 ◽

2021 ◽

Vol 11 (11) ◽

pp. 1343

Author(s):

Zhiwei He ◽

Yizhi Zhuo ◽

Zhiliang Zhang ◽

Jianying He

Keyword(s):

Adhesion Strength ◽

Rational Design ◽

State Of The Art ◽

Daily Life ◽

Ice Nucleation ◽

Current Status ◽

Ice Accretion ◽

Textured Surfaces ◽

Theoretical Limit ◽

Ice Adhesion

Ice accretion can lead to severe consequences in daily life and sometimes catastrophic events. To mitigate the hazard of icing, passive icephobic surfaces have drawn widespread attentions because of their abilities in repelling incoming water droplets, suppressing ice nucleation and/or lowering ice adhesion strength. As time elapses and temperature lowers sufficiently, ice accretion becomes inevitable, and a realistic roadmap to surface icephobicity for various outdoor anti-icing applications is to live with ice but with the lowest ice adhesion strength. In this review, surfaces with icephobicity are critically categorized into smooth surfaces, textured surfaces, slippery surfaces and sub-surface textured surfaces, and discussed in terms of theoretical limit, current status and perspectives. Particular attention is paid to multiple passive anti-icing strategies combined approaches as proposed on the basis of icephobic surfaces. Correlating the current strategies with one another will promote understanding of the key parameters in lowering ice adhesion strength. Finally, we provide remarks on the rational design of state-of-the-art icephobic surfaces with low ice adhesion strength.

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An experimental study on mitigating dynamic ice accretion process on bridge cables with a superhydrophobic coating

Experimental Thermal and Fluid Science ◽

10.1016/j.expthermflusci.2021.110573 ◽

2022 ◽

Vol 132 ◽

pp. 110573

Author(s):

Yihua Peng ◽

Ramsankar Veerakumar ◽

Zichen Zhang ◽

Haiyang Hu ◽

Yang Liu ◽

...

Keyword(s):

Experimental Study ◽

Ice Accretion ◽

Superhydrophobic Coating ◽

Accretion Process

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Current Ice Adhesion Testing Methods and the Need for a Standard: A Concise Review

Standards ◽

10.3390/standards1020011 ◽

2021 ◽

Vol 1 (2) ◽

pp. 117-133

Author(s):

Monika Bleszynski ◽

Edward Clark

Keyword(s):

Economic Losses ◽

Ice Accretion ◽

Testing Methods ◽

Adhesion Testing ◽

Standard Testing ◽

Testing Method ◽

Concise Review ◽

Main Factors ◽

Airplane Accidents ◽

Ice Adhesion

Ice accretion is a serious problem in cold climates, causing automobile and airplane accidents, as well as severe economic losses throughout various sectors. To combat these issues, many solutions have been developed, such as de-icing materials, which can delay or prevent the adhesion of ice to a surface through chemical, temperature, or physical means. To effectively assess the properties of a de-icing material, ice adhesion testing must be conducted, of which there are numerous types, each with their own characteristics. Unfortunately, the same material, tested with different methods, may provide very different ice adhesion values. This makes it difficult to properly characterize a material’s de-icing properties and compare values across the literature. In this review, we identified the main ice adhesion testing methods and compared ice adhesion values for a particular material with different testing methods. We then discussed some of the main issues with current ice testing methods and identified some of the main factors that may affect ice adhesion values, namely ice quality and the use of a mold, which may significantly affect the final ice adhesion results. Finally, we proposed a new, simple standard testing method, in an attempt to eliminate some of the issues with current ice testing methods.

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