Effects of sample geometry on the uniaxial tensile stress state at the nanoscale

Abstract

Uniaxial compression of micro- and nanopillars is frequently used to elicit plastic size effects in single crystals. Uniaxial tensile experiments on nanoscale materials have the potential to enhance the understanding of the experimentally widely observed strength increase. Furthermore, these experiments allow for investigations into the in-strength and to help to study tension-compression asymmetry. The sample geometry might influence mechanical proper- ties, and to investigate this dependence, we demonstrate two methods of uniaxial nanotensile sample fabrication. We compare the experimentally obtained tensile stress-strain response for cylindrical and square nanopillars and provide finite element method simulation results and discuss the initiation of plastic yielding in these nanosamples.