Measuring the interface stress of nanocrystalline iron

摘要

With the ongoing miniaturization of structures and devices down to the nanometer scale, we notice concomitant escalation of atoms located at surfaces or interfaces. Presence of surfaces and interfaces generates stresses in nanoscale structures that can easily exceed 1 GPa. We developed and applied a method for measuring the absolute value of grain-boundary stress. Since investigation of grain-boundary stress as well as phase-boundary stress of body-centered-cubic materials has not been addressed so far, we aimed at determining the grain-boundary stress f of nanocrystalline Fe. By means of x-ray diffraction measurements of average grain size and residual-strain-free lattice spacings, we deduced a value of f=1.1 ±0.2 N/m.