Inadequacy of Peak Detachment Force in Describing Ice Adhesion Strength: the Critical Role of Shear Force–Time Evolution in Icephobicity Assessment

Icephobicity encompasses a multifaceted definition that necessitates evaluations across various scales, from single droplets to larger ice specimens. The predominant method for evaluating icephobicity performance is ice adhesion strength (IAS) testing. Multiple geometries and scales for ice adhesion testing are proposed. The conventional key parameter derived from this test for icephobicity analysis is the peak detachment force value, which is subsequently converted to IAS (stress). Recent studies raise questions regarding this approach and challenge its adequacy for a comprehensive icephobicity assessment. To achieve a more profound understanding of the phenomena involved, this study utilizes three distinct ice adhesion test benches, all in horizontal shear geometry but under varying scales and conditions. The findings indicate that the peak force values derived from ice adhesion testing do not necessarily reflect the actual icephobicity behavior. However, force versus time evolution (obtained from force-time plots) can provide valuable insights into icephobicity, including the viscoelastic response of coatings and the underlying failure mechanisms. The beneficial aspects of force time evolution are additionally validated in the context of investigating coating durability through consecutive ice adhesion (icing/ice detachment) cycles, wherein conventional methodologies, such as wetting and morphological parameters, fail to capture the actual coating deterioration.