Tracking the sliding of grain boundaries at the atomic scale

Abstract

Grain boundaries (GBs) play an important role in the mechanical behavior of polycrystalline materials. Despite decades of investigation, the atomic-scale dynamic processes of GB deformation remain elusive, particularly for the GBs in polycrystals, which are commonly of the asymmetric and general type. We conducted an in situ atomic-resolution study to reveal how sliding-dominant deformation is accomplished at general tilt GBs in platinum bicrystals. We observed either direct atomic-scale sliding along the GB or sliding with atom transfer across the boundary plane. The latter sliding process was mediated by movements of disconnections that enabled the transport of GB atoms, leading to a previously unrecognized mode of coupled GB sliding and atomic plane transfer. These results enable an atomic-scale understanding of how general GBs slide in polycrystalline materials.

Systematic Investigation of Structural, Morphological, Thermal, Optoelectronic, and Magnetic Properties of High-Purity Hematite/Magnetite Nanoparticles for Optoelectronics

“…Similarly, the optoelectrical characteristics involving charge transfer, concentration, mobility, and conductivity strongly depend upon these factors. A slight variation in size and shape may cause significant enhancement in the above-mentioned factors [ 39 , 40 ]. Magnetite nanoparticles have an inverse spinel cubic structure, and they have a strong tendency to form aggregates due to high surface energy and strong magnetic dipole–dipole interaction [ 41 ].…”

In situTEM observations of growth mechanisms of PbO nanoparticles from a Sm-doped PMN-PT matrix

“…4(c). Then, the nanoparticle 1 grew along the (111) plane via its boundary slip, 39 because the Sm-PMN-PT particle could continually provide the PbO source. After that, a part of nanoparticle 1 and nanoparticle 3 were fused together, as shown in Fig.…”

Strain‐Induced Structure Evolution of Multimetallic Nanoplates

“…These results suggest that tensile-strain arises from stacking-faults that accumulate during the growth of the nanoplates by twin seeds and also by lattice mismatch between Pt and Ag, which is in line with the previous studies. [11,[18][19][20] While, the compressive-strain arises from the deposition of extra Pt atoms at the exterior of nanoplates, [4,5,21] caused by oxidative etching of Ag that eliminate stacking-faults. This demonstration is further supported by the strain profiles of solid and core-shell nanoplates (Figures S21c and S22c, Supporting Information), consistent with prior results.…”