Reliable and cost effective design of intermetallic Ni(2)Si nanowires and direct characterization of its mechanical properties

We report that a single crystal Ni(2)Si nanowire (NW) of intermetallic compound can be reliably designed using simple three-step processes: casting a ternary Cu-Ni-Si alloy, nucleate and growth of Ni(2)Si NWs as embedded in the alloy matrix via designing discontinuous precipitation (DP) of Ni(2)Si nanoparticles and thermal aging, and finally chemical etching to decouple the Ni(2)Si NWs from the alloy matrix. By direct application of uniaxial tensile tests to the Ni(2)Si NW we characterize its mechanical properties, which were rarely reported in previous literatures. Using integrated studies of first principles density functional theory (DFT) calculations, high-resolution transmission electron microscopy (HRTEM), and energy-dispersive X-ray spectroscopy (EDX) we accurately validate the experimental measurements. Our results indicate that our simple three-step method enables to design brittle Ni(2)Si NW with high tensile strength of 3.0 GPa and elastic modulus of 60.6 GPa. We propose that the systematic methodology pursued in this paper significantly contributes to opening innovative processes to design various kinds of low dimensional nanomaterials leading to advancement of frontiers in nanotechnology and related industry sectors.