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Related papers: Emerging hierarchical dislocation structures: Insi…

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Viscoplastic flow of polycrystalline metallic materials is the result of motion and interaction of dislocations, line defects of the crystalline structure. In the microstructural (physics-based) constitutive model presented in this paper,…

Materials Science · Physics 2018-09-11 S. Amir H. Motaman , Ulrich Prahl

In small-scale metallic systems, collective dislocation activity has been correlated with size effects in strength and with a step-like plastic response under uniaxial compression and tension. Yielding and plastic flow in these samples is…

Materials Science · Physics 2019-07-18 Xiaoyue Ni , Stefanos Papanikolaou , Gabriele Vajente , Rana X Adhikari , Julia R. Greer

Irradiation-induced ductility loss is a major concern facing structural steels in next-generation nuclear reactors. Currently, the mechanisms for this are unclear but crucial to address for the design of reactor components. Here, the…

Cellular patterns formed by self-organization of dislocations are a most conspicuous feature of dislocation microstructure evolution during plastic deformation. To elucidate the physical mechanisms underlying dislocation cell structure…

Materials Science · Physics 2020-07-20 Ronghai Wu , Michael Zaiser

A correlation is established between the macro-scale friction regimes of metals and a transition between two dominant atomistic mechanisms of deformation. Metals tend to exhibit bi-stable friction behavior -- low and converging or high and…

Materials Science · Physics 2018-05-23 Nicolas Argibay , Michael E. Chandross , Shengfeng Cheng , Joseph R. Michael

Structural changes in a glass due to deformation are subtle and difficult to quantify using conventional imaging and diffraction techniques. Additionally, transmission electron microscopy (TEM) sample preparation using energetic ions often…

The image fractal analysis is actively used in all science branches. In particular in materials science the fractal analysis is applied to study microstructure of deformed metals because its structure can be interpreted as the fractal…

Materials Science · Physics 2012-05-01 Anatoliy Zavdoveev , Yan Beygelzimer , Victor Varyukhin , Boris Efros

For high (angular) resolution electron backscatter diffraction (HR-EBSD), the selection of a reference diffraction pattern (EBSP0) significantly affects the precision of the calculated strain and rotation maps. This effect was demonstrated…

Materials Science · Physics 2023-02-21 Abdalrhaman Koko , Vivian Tong , Angus J. Wilkinson , T. James Marrow

Heterostructures consisting of PbZr0.2Ti0.8O3 and PbZr0.4Ti0.6O3 films grown on a SrTiO3 (100) substrate with a SrRuO3 bottom electrode were prepared by pulsed laser deposition. Using the additional interface provided by the ferroelectric…

Materials Science · Physics 2009-03-27 Ludwig Geske , I. B. Misirlioglu , Ionela Vrejoiu , Marin Alexe , Dietrich Hesse

Scanning transmission electron microscopy (STEM) has become the technique of choice for quantitative characterization of atomic structure of materials, where the minute displacements of atomic columns from high-symmetry positions can be…

Materials Science · Physics 2021-10-05 Kevin M. Roccapriore , Nicole Creange , Maxim Ziatdinov , Sergei V. Kalinin

Validating dislocation patterning models against in situ imaging experiments is a longstanding goal in materials physics. Here, we provide the first direct morphological comparison of such models. Using in situ Dark-Field X-ray Microscopy…

The intersection between dislocations and a Ag(111) surface has been studied using an interplay of scanning tunneling microscopy (STM) and molecular dynamics (MD). Whereas the STM provides atomically resolved information about the surface…

Organic molecular crystals encompass a vast range of materials from pharmaceuticals to organic optoelectronics and proteins to waxes in biological and industrial settings. Crystal defects from grain boundaries to dislocations are known to…

Materials Science · Physics 2023-09-01 Sang T. Pham , Natalia Koniuch , Emily Wynne , Andy Brown , Sean M. Collins

Understanding the mechanism of martensitic transformation is of great importance in developing advanced high strength steels, especially TRansformation-Induced Plasticity (TRIP) steels. The TRIP effect leads to enhanced work-hardening rate,…

Materials Science · Physics 2016-12-28 Jiabin Liu , Qiong Feng , Xiaoyang Fang , Hongtao Wang , Jian Lu , Dierk Raabe , Wei Yang

Layered materials (LMs) are at the centre of an ever increasing research effort due to their potential use in a variety of applications. The presence of imperfections, such as bi- or multilayer areas, holes, grain boundaries, isotropic and…

Metallic films are important in catalysis, magneto-optic storage media, and interconnects in microelectronics, and it is crucial to predict and control their morphologies. The evolution of a growing crystal is determined by the behavior of…

Materials Science · Physics 2016-11-03 C. Ratsch , P. Ruggerone , M. Scheffler

Dislocations are one-dimensional (1D) topological line defects where the lattice deviates from the perfect crystal structure. The presence of dislocations transcends condensed matter research and gives rise to a diverse range of emergent…

A micromorphic computational homogenization framework has recently been developed to deal with materials showing long-range correlated interactions, i.e. displaying patterning modes. Typical examples of such materials are elastomeric…

Soft Condensed Matter · Physics 2024-06-21 S. Maraghechi , O. Rokoš , R. H. J. Peerlings , M. G. D. Geers , J. P. M. Hoefnagels

Additive manufacturing (AM) by laser powder bed fusion (L-PBF) leads to the formation of a rich, hierarchical microstructure, including dislocation cell structures and elemental segregation. This structure has profound impacts on the…

Materials Science · Physics 2021-12-16 Mengkun Tian , Jahnavi Desai Choundraj , Thomas Voisin , Y. Morris Wang , Josh Kacher

Crystal defects play a large role in how materials respond to their surroundings, yet there are many uncertainties in how extended defects form, move, and interact deep beneath a material's surface. A newly developed imaging diagnostic,…

Data Analysis, Statistics and Probability · Physics 2020-08-13 Arnulfo Gonzalez , Marylesa Howard , Sean Breckling , Leora E. Dresselhaus-Marais