Buckling modes of polymer membranes restricted by metal wires

Using field emission SEM, the thermal deformation of metal-wire/polymer- membrane/glass structures was observed. The thermal mismatch between the metal wire and the polymer membrane can trigger new instability modes of the polymer membrane. In the direction parallel to the axis of the wire, the orthogonal wave, oblique wave, or crumpled wave buckling mode with micro wavelength arises, while in the perpendicular direction, harmonic nano wrinkles appear on the polymer membrane. These two kinds of mutually orthogonal multi-scale instability modes can form a novel micro/nano buckling pattern. This paper discusses the formation mechanisms of these buckling patterns. The research results can provide insights into the optimization design and manufacturing process control of metal-wire/polymer-membrane structures.