Digital micromirror device (DMD)-based high-cycle tensile fatigue testing of 1D nanomaterials

Fatigue behavior of nanomaterials could be critical for numerous nanomechanical applications involving dynamic deformation processes, such as in flexible electronics devices. Despite that substantial research efforts have been made on mechanical characterization of various one-dimensional (1-D) nanomaterials under quasi-static loading, very few works have been done so far on the challenging fatigue testing of individual 1-D nanostructures, in particular for their high-cycle fatigue behavior. Here, instead of designing a new device, commercially available digital micromirror device (DMD) has been adopted to develop a cost-effective platform for investigating the high-cycle fatigue responses of individual nanowires/nanotubes, due to its ultra-high actuation frequency (up to 32,000 Hz), under cyclic tensile straining. We further demonstrated that, due to the small footprint of this MEMS-type device and its remote controlling mechanism, desired in situ tensile fatigue testing of individual nanowire can be achieved inside a scanning electron microscope (SEM). In addition, the millions of independent movable micromirrors on a single DMD chip make our platform particularly suitable for high-throughput testing of various 1-D nanomaterial samples for the statistical analysis of their fatigue characteristics.