The deformation behavior of nanoparticles continues to be an exciting area for materials research. Typically, nanoparticles show a conspicuous lack of dislocations, even after significant deformation. Therefore, it has been suggested that dislocations cannot exist or/do not play a role on the deformation of nanoparticles. In situ TEM nanoindentation is a critical tool for addressing this issue ...

Experimental studies of pH-responsive expansile nanoparticles (eNPs) have been carried out using tunable resistive pulse sensing (TRPS) and nanoindentation. The eNPs are initially ~200 nm in diameter, but increase in size owing to a compositional change resulting from cleavage of pH-labile protecting groups on the polymer backbone at low pH. TRPS detected expected changes in the size of eNPs, m...

Nanoscale research of bulk solid surfaces, thin films and micro- and nano-objects has shown that mechanical properties are enhanced at smaller scales. Experimental studies that directly compare local with global deformation are lacking. In this research, spherical Au nanoparticles, 500 nm in diameter and 100 nm thick Au films were selected. Nanoindentation (local deformation) and compression te...

have recognized that surface contacts between materials are highly dependent on their mechanical properties1,2. Many different indentation and impression tests have been developed in an effort to measure such mechanical properties from a contact of known geometry. In the past two decades, however, a veritable revolution has occurred in indentation testing, owing to the development of new sensor...

Nanoindentation simulations on a binary metallic glass were performed under various strain rates by using molecular dynamics. The rate-dependent serrated plastic flow was clearly observed, and the spatiotemporal behavior of its underlying irreversible atomic rearrangement was probed. Our findings clearly validate that the serration is a temporally inhomogeneous characteristic of such rearrangem...

The time-independent and time-dependent mechanical behavior of electrochemically lithiated silicon was studied with nanoindentation. As indentation was performed with continuous stiffness measurements during loading and load-hold, new insight into the deformation behavior of lithiated silicon is furnished. Supporting other research, Young's modulus and the hardness of lithiated silicon are foun...

Nix and Gao established an important relation between microindentation hardness and indentation depth. Such a relation has been verified by many microindentation experiments (indentation depths in the micrometer range), but it does not always hold in nanoindentation experiments (indentation depths approaching the nanometer range). We have developed a unified computational model for both microan...

We describe in detail, the design, construction, and testing of a specimen holder that allows for the nanoindentation of surfaces while viewing in cross-section in a high voltage transmission electron microscope (TEM). This nanoindentation specimen holder, having three-axis position control of a diamond indenter in combination with micromachined specimens, allows for the first time the dynamic ...

Since the nanoindentation technique is able to measure the mechanical properties of extremely thin layers and small volumes with a high resolution, it also became one of the most important testing techniques for thin polymer layers and coatings. This work is focusing on the characterization of polymers using nanoindentation, which is dealt with by means of numerical computation, experiments and...

INTRODUCTION Cortical bone is an anisotropic material, and its mechanical properties are determined by its composition as well as its microstructure. On the microstructure level (a few microns), cortical bone is composed primarily of single osteons and interstitial lamellae. Nanoindentation has been shown to be an effective technique to probe mechanical properties of microstructures at the micr...