Probing the three-dimensional strain inhomogeneity and equilibrium elastic properties of single crystal Ni nanowires

TL;DR

This study uses 3D x-ray coherent diffraction imaging to map strain distribution and elastic properties of single crystal Ni nanowires, revealing how strain varies with wire width and enabling Young's Modulus prediction.

Contribution

It introduces a method to map 3D strain in nanowires and correlates strain inhomogeneity with elastic properties, providing new insights into nanoscale mechanical behavior.

Findings

Strain inhomogeneity varies with wire width.

Surface tensile strain increases with width.

Young's Modulus can be predicted from lattice distortion.

Abstract

We employ three dimensional x-ray coherent diffraction imaging to map the lattice strain distribution, and to probe the elastic properties of a single crystalline Ni (001) nanowire grown vertically on an amorphous Si02 || Si substrate. The reconstructed density maps show that with increasing wire width, the equilibrium compressive stress in the core region decreases sharply while the surface tensile strain increases, and gradually trends to a nonzero constant. We use the retrieved projection of lattice distortion to predict the Young's Modulus of the wire based on the elasticity theory.