Interfacial shear stress transfer between elastoplastic fiber and elastic matrix

Interfacial mechanics between elastoplastic fiber and elastic substrate/matrix is of critical importance for a range of applications such as metal nanowires on polymer substrate for flexible and stretchable electronics and metal fibers in ceramic matrix for multifunctional composites. Here analytical models of an elastoplastic fiber (e.g., nanowire) on the as-prepared or chemically treated elastic substrate are derived by using the nonlinear and bilinear cohesive shear-lag models, respectively, for the fiber/substrate interface. For the first time, the effect of plastic mechanical behavior of the fiber on the interfacial shear stress transfer characteristics is studied. Different cases considering the length of the plastic zone relative to the bonded, sliding, damaged and debonded zones are investigated. The effect of the substrate strain, nanowire length and diameters is investigated to predict the mechanical behavior of the nanowire, which provides a guide to the experiment with metal nanowires on a polymer substrate. This work can be extended to other elastoplastic fibers including 2D nanomaterials, metal particles, and metal thin films on elastic substrates or matrices.