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Many engineering systems operating in a cold environment are challenged by ice accretion, which unfavorably affects their aerodynamics and degrades both their performance and safety. Precise characterization of ice adhesion is crucial for an effective design of ice protection system. In this paper, a fracture mechanics-based approach incorporating single cantilever beam test is used to characterize the near mode-I interfacial adhesion of a typical ice/aluminum interface with different surface roughness. In this asymmetric beam test, a thin layer of ice is formed between a fixed and elastically deformable beam subjected to the applied loading. The measurements showed a range of the interfacial adhesion energy (GIC) between 0.11 and 1.34 J/m 2, depending on the substrate surface roughness. The detailed inspection of the interfacial ice fracture surface, using fracture surface replication technique, revealed a fracture mode transition with the measured macroscopic fracture toughness.

Airborne, marine and ground structures are vulnerable to atmospheric icing in cold weather operation conditions. Most of the ice adhesion-related work have focused on the mechanical ice removal strategies because of practical considerations, while limited literature is available for fundamental understanding of the ice adhesion process. Here, we present a fracture mechanics-based approach to characterize interfacial fracture parameters for the shear behavior of a typical ice/aluminum interface. An experimental framework employing two complementary tests (1) lap shear and (2) shear push-out tests was introduced to assess the mode-II fracture parameters for the selected aluminum/ice interface. Both analytical (shear-lag analysis) and numerical (finite element analysis incorporating cohesive zone method) models were used to evaluate shear fracture parameters.

Structures in cold weather environments are susceptible to atmospheric ice formation. A fracture mechanics based approach is proposed for in situ characterization of the interfacial fracture energy of ice on different substrates. This paper summarizes the development of the experimental and analytical framework to measure the ice adhesion energy, calibrated on static ice. The testing configuration utilizes a shaft-loaded blister test to produce stable crack propagation, from a well-defined pre-crack at the interface of the ice layer and the substrate. Measurements of the fracture energy are taken over a range of ice thicknesses and surface roughnesses. The developed analytical framework to estimate adhesion energy are verified and calibrated via finite element numerical simulation of the proposed geometric configuration and employing cohesive surfaces along the interface to simulate the crack nucleation and propagation process.