In situ characterization of the mechanical properties of nanoparticles and nanoscale structures

Abstract

One major difficulty in characterizing the mechanical properties of nanoscale materials is the inherently small size of the structures of interest. With traditional nanomechanical-testing techniques, the inability to see nanoscale structures directly can leave a number of unknowns. For example, the crystallographic orientation of the sample, the presence of any pre-existing defects, and even the certainty that contact was both made and maintained during deformation must necessarily be assumed. While the transmission electron microscope (TEM) is uniquely well-suited for determining these unknowns, mechanical testing inside the TEM has consisted of, until quite recently, predominantly qualitative studies [1–3]. Over the past decade a number of advances in in situ indentation specimen holders, such as the integration of not only a piezoelectric actuator, but also a capacitive transducer, have allowed for the development of a holder which is capable of quantitative load-displacement measurements [4].