Peeling behavior of a bio-inspired nano-film on a substrate

Abstract

a b s t r a c tA peeling model is proposed to analyze the peeling properties of bio-mimetic nano-films using the finite element method (FEM) and theoretical approach. The influences of the nano-film's adhesion length, thickness, elastic modulus, roughness and peeling angle on the peeling force were considered as well as the effect of the viscoelastic behavior. It has been found that the effective adhesion length, at which the peeling force attained maximum, was much smaller than the real length of nano-films; and the shear force dominated in the case of smaller peeling angles, whereas, the normal force dominated at larger peeling angles. The total peeling force decreased with an increasing peeling angle. Two limiting values of the peeling-off force can be found in the viscoelastic model, which corresponds to the smaller and larger loading rate cases. The effects of nano-film thickness and Young's modulus on peeling behaviors were also discussed. The results obtained are helpful for understanding the micro-adhesion mechanisms of biological systems, such as geckos.

Effects of surface wettability on gecko adhesion underwater

“…Experimental and theoretical studies on gecko adhesion mechanisms have been carried out extensively during the past decades, most of which mainly focus on the van der Waals adhesion mechanism on dry solid surfaces [5,[8][9][10][11]. However, there are more than 1400 species of geckos in the world and different species possess different natural habitats and living conditions [12].…”

Recent advances in gecko adhesion and friction mechanisms and development of gecko-inspired dry adhesive surfaces

“…The width of the spatula w is 200 nm, which is close to the actual geometric dimension of the spatula. The Kendall model has provided new insights into the peeling mechanism of gecko detachment [51,52]. It is also important to note that the biomechanics of a gecko walking on a surface reveals the use of a particular configuration, a Y-shaped geometry/configuration [1,20,52].…”

Design of gecko-inspired fibrillar surfaces with strong attachment and easy-removal properties: a numerical analysis of peel-zone

“…The use of micro-and nano-structured fibrillar surfaces to mimic gecko seta arrays has attracted much interest during the past decade [9,12,[21][22][23][24][25][26][27][28]. Micro-fibrillar surfaces that use microfabricated hole array masters [2,9,10,21] and a nanowire surface with a larger aspect ratio and a high Young's modulus [7] have also been fabricated.…”