Design and preparation of icephobic metal-based surfaces

Resumen

Interest for icephobic materials is growing up in recent years. A wide range of surfaces are proposed as anti-icing. These surfaces hold different properties that mitigate ice formation. However, under extreme conditions, most surfaces fail because ice is formed on them. For this reason, surfaces with de-icing properties are also developed. The main de-icing property is low ice adhesion, for continuous ice release. Design of low-adhesion surfaces with longer service life and minor maintenance costs involves exciting interdisciplinary scientific challenges and their incipient scaling-up to industrial applications is clear. Still there is no single and simple solution for mitigating the adhesion of ice to substrates in real-world applications. In this dissertation, we studied icephobic elastomeric surfaces. Elastic materials are postulated for low adhesion due to their deformability. Further, surface deformability can be combined with ice-repelling properties, or be employed to fabricate oil-infused surfaces with icephobic performance. We analysed the ice detachment mechanisms on PDMS surfaces and compared the results with rigid materials. Wetting affects both ice formation and release so a proper understanding is mandatory. The analysis of wetting phenomena on elastic surfaces should be carefully conducted. Contact line dynamics of sessile drops is altered by surface elasticity. Consequently, the typical methods to evaluate wetting properties of elastic surfaces are call into question. A new protocol to properly measure contact angles hysteresis of PDMS surfaces is proposed. A large number of elastic surfaces with very different values of elastic modulus and wetting properties were prepared. Ice adhesion to these surfaces was studied from two different modes (tensile and shear). The adhesion strength values were related with the surface properties and the role of deformability was examined. We also prepared polymer infused surfaces (resembling slippery liquid-infused porous surfaces). For both types of surfaces (elastic and oil-infused elastic), low iceadhesion was reached for a suitable combination of the material properties. Finally, the mechanical durability of the elastomeric surfaces was evaluated. Two wear tests were performed: standard abrasion test and physical erosion test, that simulate prolonged damage under outdoors conditions. The elastic and oil-infused elastic surfaces revealed great resistance to mechanical wear. Particularly, the oil-infused elastic surfaces maintained its low ice-adhesion property unaltered. In this work, we propose surfaces with durable de-icing properties potentially applicable to real ambients. Moreover, field tests were performed to evaluate the real applicability of the surfaces.