[CCoE Notice] Thesis Defense Announcement: On Physics of Durable Ice Phobic Surfaces

[Grayson, Audrey A]

Peyman Irajizad PhD Defense

Title: On Physics of Durable Ice Phobic Surfaces

Location: Eng building #1, Mechanical small conference room.

Committee Members: Dr. Hadi Ghasemi, Dr. Dong Liu, Dr. Megan Robertson, Dr. Rodolfo Ostilla Monico, Dr. Di Yang

Date: November 30, 2018

Time: 2-4PM



The abstract is :

Icephobic surfaces have a critical footprint on human daily lives ranging from

aviation systems and infrastructures to energy systems, but creation of these surfaces for

low-temperature applications remains elusive. Non-wetting, liquid-infused and hydrated

surfaces have inspired routes for development of icephobic surfaces. However, high

freezing temperature, high ice adhesion strength and subsequent ice accretion, low

mechanical durability, and high production cost have restricted their practical applications.

A comprehensive definition for icephobicity through thermodynamics, heat transfer and

mechanics of ice/water-material interface and elucidate physic-based routes was provided

through which nano-scale could help to achieve exceptional icephobic surfaces. Here, we

cast fundamentals of two new physical concept called magnetic slippery surfaces and

stress-localization to develop two new icephobic surfaces with extremely low adhesion and

exceptional mechanical, chemical and environmental durability.

In the first concept, we report a new magnetic slippery surface outperforming state-of-theart

icephobic surfaces with an ice formation temperature of -34 °C, 2-3 orders of magnitude

higher delay time in ice formation, extremely low ice adhesion strength (~2 Pa), and

stability in shear flows up to Reynolds number of 105. In these surfaces, we exploit the

magnetic volumetric force to exclude the role of solid-liquid interface in ice formation. We

show that these inexpensive surfaces are universal and can be applied to all types of solids

(no required micro/nano structuring) with no compromise to their unprecedented

properties.

In stress localization method, new physical concept and corresponding material paradigm

to develop highly durable icephobic materials. These materials utilize stress-localization

function to initiate crack at the ice-material interface and consequently minimize ice

adhesion on the surface. Stress-localization leads to a shear force at the interface for

detachment of ice from the material. The developed concept is implemented in elastomers

and the superior icephobicity of these materials compared to state-of-the-art materials is

demonstrated. These forms of icephobic materials demonstrate excellent mechanical,

chemical and environmental durability with no change of characteristics under extreme air

and water shear flows. Furthermore, these icephobic materials does not change the

aerodynamic characteristics of airfoils thereby providing a promising solution for

aerospace application. In contrast to surface-modified coatings, the icephobicity of these

materials is a volumetric property and no degradation in the performance occurs in longterm

operation under mechanical loadings. The developed concept of stress-localization

reduces adhesion of solids on a material by an order of magnitude with no compromise in

mechanical properties. We envision that the developed physical concept opens a rational

route to minimize adhesion of any solid species (i.e. ice, gas hydrate, dust, and even biospecies)

on a surface with omnipresent application in transportation systems (aviation, cars

and vessels), energy/water systems, bio-sciences and even space systems..


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