A New Method for Measuring the Ice Adhesion Strength of Anti-Icing Coatings

Abstract

This work provides a new method for measuring the ice adhesion strength of anti-icing coatings. An extensive literature review was performed to investigate the different means by which other researchers have performed ice adhesion tests. A better understanding of ice adhesion was obtained by investigating ice characteristics, mechanical properties, and how ice adheres to surfaces. In this context, the phenomena of icephobicity and superhydrophobicity as well as the correlation between the two were studied. It was also searched for factors concerning ice formation and environmental aspects of a testing apparatus that would promote brittle failure and adhesive fractures. Decisions about the design and implementation were taken on this basis. Factors concerning the interfacial stress distribution were further investigated through FE analyses in COMSOL Multiphysics.Through a series of tests and the FEA, the apparatus demonstrated its capabilities. It showed a great feasibility and effectiveness in measuring the ice adhesion strengths of coatings with good accuracy and repeatability. The IAS of the steel reference samples measured 0.59 MPa, comparable to values reported in the literature. The IAS of the coatings was in the range 0.23-0.64 MPa, and hence with ARF values between 2.6 and 0.9. No correlation between the average surface roughness and adhesion strengths among the coatings was observed. However, a decrease in roughness as a result of inflicted coating damage led to an almost linear increase in adhesion strength of a given coating.From the results obtained, it was concluded that by far the most critical factor regarding the shear stress distribution in the ice/solid interface is the distance from the indenter to the interface, with an exponential change with the distance. Other factors, such as the E-modulus of the components, and keeping the ice mold on during testing, does not seem to affect the results significantly. The proposed method has proven to be effective, very easy to use, and able to provide reliable and repeatable results with a low degree of scattering. With good opportunities for customizations, it is envisioned that this is a method that could meet many needs in the process of coating testing; both in the fabrication process, and in the process of selecting coatings that satisfies customer needs.