Failure of Particle-Laden Interfaces Studied Using The Funnel Method

Abstract We develop a method to explore the mechanical response of particles on a liquid-air interface under biaxial tension. Particles were laser cut with designed 2D geometries that interact in a predictable manner through capillary effects. When such particles were arranged into a raft on the water-air interface in a funnel, raising the water level induced deformation and ultimately failure of the raft. While particles that strongly attract one another can be strained further before they fracture, weakly interacting particles are able to move to heal fractures in a manner that is reminiscent of crack healing in ductile materials. Anisotropic particles delay the onset of failure but prevent rearrangement owing to particles locking into fixed orientations relative to their neighbors. These results illustrate the importance of interparticle interactions in determining the emergent mechanical properties of particle rafts.