Article
Nanoscience & Nanotechnology
J. -E. Brandenburg, J. Seo, K. Eto, D. A. Molodov, S. Tsurekawa
Summary: The study used nanoindentation to investigate the local mechanical properties near 1010 tilt grain boundaries in magnesium bicrystals with different misorientation angles. It was found that critical shear-stress for the second pop-in differed substantially for grain boundaries with different structures, indicating important mechanical property variations in these boundaries.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Chemistry, Physical
Yusuke Ootani, Momoji Kubo
Summary: This study elucidates the design principle for bendable molecular crystals through simulation experiments. It reveals that plasticity and sufficient flexibility are required for a crystal to exhibit bendable characteristics, while brittleness limits the bendability of molecular crystals.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Materials Science, Ceramics
Arezoo Zare, Mo-Rigen He, Michael Straker, M. V. S. Chandrashekhare, Michael Spencer, Kevin J. Hemker, James W. McCauley, K. T. Ramesh
Summary: The study investigated the out-of-plane anisotropy in the mechanical response of boron carbide single crystals, finding significant differences in indentation modulus and hardness among different crystal orientations. It also examined the influence of in-plane anisotropy on indentations, and observed deformation behavior through pop-in events. The research provided insights into the failure mechanism of boron carbide, highlighting the potential role of crystal slip in quasi-plasticity and formation of amorphous bands leading to cracking and fragmentation.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2022)
Article
Nanoscience & Nanotechnology
F. J. Dominguez-Gutierrez, S. Papanikolaou, A. Esfandiarpour, P. Sobkowicz, M. Alava
Summary: The study investigates the effects of high temperature on the mechanical deformation properties of single crystalline Mo under nanoindentation, revealing that temperature increase changes dislocation densities, mechanisms, atomic displacements, and hardness. The characteristic formation of [001] dislocation junctions and high-temperature stability may be responsible for the persistent thermomechanical stability of Mo, contrasting with other BCC metals.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Materials Science, Multidisciplinary
X. K. Shang, S. Pan, Q. W. Guan, B. B. He
Summary: This study focused on the mechanical behavior of single austenite grain with different orientations in TWIP steel through nanoindentation test. Deformation twins were found in grains with [0 0 1] orientation, while they were absent in grains with [1 1 1] orientation. High-density dislocations were observed in both orientations after nanoindentation.
METALS AND MATERIALS INTERNATIONAL
(2022)
Article
Chemistry, Physical
Javier Varillas, Giovanni Ciccotti, Jorge Alcala, Lamberto Rondoni
Summary: Mathematical relations concerning particle systems require applicability conditions. The Jarzynski equality, a mechanical theory, shows surprising generality in determining free-energy variations for non-equilibrium processes. However, it can be process-dependent and its verification may be challenging.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Materials Science, Multidisciplinary
Daniel N. Blaschke
Summary: This work aims to derive a general anisotropic solution for pure screw dislocations applicable to slip systems featuring a reflection symmetry in anisotropic crystals, in order to study pure screw dislocations without mixing with edge dislocations. However, further generalizations to arbitrary mixed dislocations as well as regularizations of the dislocation core are left for future work.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2021)
Article
Chemistry, Multidisciplinary
Raz Samira, Adam Cohen, Fernando Patolsky, Noa Lachman
Summary: In this study, the long-term durability of thick multi-walled carbon nanotubes (MWCNTs) under cyclic loading was assessed using in situ transmission electron microscope (TEM) observations. The tube's structural resilience was demonstrated after 68 loading-unloading cycles, and the stiffness of the tube was calculated to be in a range of 0.15 to 0.28 TPa, comparable to literature values. These in situ tests provide valuable insights into the fatigue resistance of CNTs and can guide the design of CNT-based devices for specific applications.
Article
Chemistry, Physical
Qaisar Khushi Muhammad, Lukas Porz, Atsutomo Nakamura, Katsuyuki Matsunaga, Marcus Rohnke, Juergen Janek, Juergen Roedel, Till Froemling
Summary: This study demonstrates that dislocations can be used to modulate the conductivity of ceramic materials by accurately controlling the arrangement of dislocations, achieving effects similar to chemical doping. By combining various testing methods, mechanical control of the interaction between neighboring dislocations is achieved, allowing differentiation between conducting pathways and separated charge regions.
Article
Materials Science, Multidisciplinary
Zhijie Ge, Hongjun Li, Xiao Cheng
Summary: Nanoindentation experiments were conducted to study the plastic deformation mechanism of single crystal diamond. It was found that the plastic characteristic of diamond was due to phase transition rather than dislocation slip. The nucleation and growth of 1/2[110]{111} complete dislocation ring during the plastic deformation of diamond were determined by observing pop-in events and dislocation evolution. The formation and growth of the dislocation ring were attributed to the phase transition from disordered sp3 to ordered sp2 carbon atoms. It was concluded that phase transition is an important excitation source for plastic deformation at the atomic scale in diamond.
DIAMOND AND RELATED MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Songbo Zhou, Feng Hu, Kun Wang, Chengyang Hu, Hangyu Dong, Xiangliang Wan, Shi Cheng, R. D. K. Misra, Kaiming Wu
Summary: Different microstructures at different scales were obtained through one and two-step isothermal transformation. The two-step isothermal transformation resulted in an increased boundary fraction and density of the K-S relationship, promoting the nucleation of bainite and achieving a refined microstructure. The nanoindentation experiments showed that the deformation/transformation behavior of blocky martensite/retained austenite (M/RA) was influenced by the quantity of retained austenite transformation.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2022)
Article
Chemistry, Physical
Daniel N. Blaschke, Khanh Dang, Saryu J. Fensin, Darby J. Luscher
Summary: We discuss the theoretical solution to the differential equations governing accelerating edge dislocations in anisotropic crystals. This is crucial for understanding high-speed dislocation motion, including the unresolved question of transonic dislocation speeds, and subsequent high-rate plastic deformation in metals and other crystals.
Review
Chemistry, Multidisciplinary
Brian K. Tanner
Summary: This article provides a brief review of X-ray topographic studies of crystals grown from solution. The unique dislocation configurations of such crystals are described, with a particular focus on Klapper's explanation involving the minimization of elastic energy per unit growth length of a dislocation. It is demonstrated that these principles apply not only to crystals grown from low temperature solution, but also to hydrothermal growth and growth from fluxed melts. Recent studies on protein crystal growth have revealed similar dislocation configurations and characteristics to those of ionic and small organic molecule crystals grown from solution.
CRYSTAL GROWTH & DESIGN
(2023)
Article
Multidisciplinary Sciences
D. Giuntini, S. Zhao, T. Krekeler, M. Li, M. Blankenburg, B. Bor, G. Schaan, B. Domenech, M. Mueller, I Scheider, M. Ritter, G. A. Schneider
Summary: Supercrystalline nanocomposites consist of organically functionalized inorganic nanoparticles arranged into periodic structures with superlattice imperfections. When subjected to indentation, these materials exhibit deformation patterns similar to those seen in single crystals, accommodating plastic deformation through pile-ups, dislocations, and slip bands. The behavior of supercrystalline nanocomposites can be well described by classic shear theories of crystalline materials, displaying elastoplastic behavior along with compaction.
Article
Physics, Applied
J. Chen, S. J. Fensin
Summary: This study shows that the local structure variation plays a crucial role in controlling damage nucleation under high strain-rate shock loading, but is not important under pure tensile loading. The specific loading conditions determine whether the local interface structure matters, as it alters the deformation behavior and subsequently affects damage nucleation and evolution.
JOURNAL OF APPLIED PHYSICS
(2021)
Article
Materials Science, Multidisciplinary
Nizar Lefi, Salem Neily, Roland Bonnet
Summary: This paper investigates the elastic field in a bi-material crystal with an angular dislocation line with one branch placed in the crystal and the other along a strongly bound or welded interface. The analysis formulates the elastic field of a closed dislocation loop and solves it using the knowledge of the Green's tensor of the bi-material. The study provides a faster calculation method and has important implications for solving interfacial angular dislocation problems.
PHILOSOPHICAL MAGAZINE
(2024)
