Heterogeneity in the Small-Scale Deformation Behavior of Disordered Nanoparticle Packings

Abstract

Atomic force microscopy-based nanoindentation is used to image and probe the local mechanical properties of thin disordered nanoparticle packings. The probed region is limited to the size of a few particles, and an individual particle can be loaded and displaced to a fraction of a single particle radius. The results demonstrate heterogeneous mechanical response that is location-dependent. The weak locations may be analogous to the "soft spots" previously predicted in glasses and other disordered packings.

Friction and Adhesion Govern Yielding of Disordered Nanoparticle Packings: A Multiscale Adhesive Discrete Element Method Study

“…To match the characteristics of the previously investigated alumina-coated silica DNPs, 11 4000 particles with a uniform diameter distribution within 20.0 ± 4.8 nm are randomly generated within a box. In such a system, gravity may be ignored.…”

“…In prior research, we investigated the plastic deformation of silica DNPs using atomic force microscopy (AFM)-based single-particle indentation. 11 Using high-resolution imaging and tracking, we succeeded in reproducibly indenting on top of a single chosen nanoparticle in the packing. This stands in contrast to conventional nanoindentation experiments, where resolution at the individual particle level (i.e., atoms or molecules) is not achievable.…”

Multifiller nanocomposites containing gadolinium oxide and bismuth nanoparticles with enhanced X‐ray attenuation property

“…35,38,39 Young's modulus, defined as stress to strain ratio for a material which behaves elastically, is a measure of stiffness of a material. 40,41 Further, polymers exhibit adhesion hysteresis due to deformation which is an outcome of material property such as polymer-nanofiller interaction at interface and distribution of nanofillers within polymer matrix of nanocomposites. 38,40,[42][43][44][45] A poor interfacial interaction reduces the mechanical strength and thermal stability.…”

“…40,41 Further, polymers exhibit adhesion hysteresis due to deformation which is an outcome of material property such as polymer-nanofiller interaction at interface and distribution of nanofillers within polymer matrix of nanocomposites. 38,40,[42][43][44][45] A poor interfacial interaction reduces the mechanical strength and thermal stability. The complexity of interfacial interaction further increases in a multifiller nanocomposite due to the presence of two or more types of interfacial interaction between multifiller components.…”

Local manipulation of metamagnetism by strain nanopatterning

“…[5][6][7][8] From the broad range of methods to perform nanopatterning, mechanical nanoimprinting, which uses local stress applied by means of a tip, is a convenient technique because, in spite of its simplicity, it allows generating structures eventually smaller than those of standard optical methods which cannot easily go below the light diffraction limit. Via mechanical nanopatterning, properties such as crystallinity, 9,10 nanoparticle arrangement, 11 ferroelectricity, 12,13 electric transport 13 or metal-insulator transitions, 14 amongst others, can be controlled at the nanoscale. Remarkably, mechanical nanopatterning of nonferromagnetic alloys can also be used to obtain nanomagnetic motifs (i.e., magnetic nanolithography).…”