Resolving Dual Processes in Complex Oscillatory Yielding

The complex two-step yielding observed in some soft materials under oscillatory shearing is shown to result from two independent phenomena. The first step at small deformations corresponds to elastic softening, while the larger deformation feature corresponds to yielding. This interpretation is supported by experimental recovery rheology data and the construction of a rheo-physical model. Our findings elucidate the mechanisms governing complex yielding and underscore the insight afforded by recovery experiments, which decouple the underlying physics between recoverable and unrecoverable processes.