In situ TEM nanoindentation and deformation of Si-nanoparticle clusters

The mechanical behaviour of clusters of interacting 50 nm Si nanoparticles has been characterized in real-time using a custom made in situ transmission electron microscope nanoindentation holder with axial stiffness 1800 N m(-1). The clusters of Si nanoparticles are mechanically loaded through a displacement controlled indentation using a W-tip indenter and experienced 0-55 mu N load. Real-time imaging of the deformation of the nanoparticle clusters shows localized orientation changes in the individual Si nanoparticles during loading followed by fracture of the cluster along a weak interface between two nanoparticles within the cluster.