Competing buckling of micro/nanowires on compliant substrates

Two buckling modes (out-of-surface and in-surface buckling) of micro/nanowires on elastomeric substrates are observed. Here, theoretical analysis and numerical simulations are presented to discover the critical factors that govern the competition between the two buckling modes. The aim is to fabricate buckled structures in selectable manner, instead of studying the buckling behavior of each individual buckling mode. The result shows the material properties have large influence on the critical buckling strain, but no significant influence on buckling competition behavior, the buckling mode is mainly determined by the micro/nanowires cross-section morphology. For cross-sections with equal moment of inertia in in-surface and normal-to-surface directions, in-surface buckling is always favorable. However, micro/nanowires with unequal moment of inertia, e.g. ellipse, rectangle and trapezoid, are usually fabricated in practical micro/nanofabrication such as through electrospinning and etching, and their influence on buckling modes is investigated.