Results 71 to 80 of about 52,903 (306)

Continuum Representation of Systems of Dislocation Lines: A General Method for Deriving Closed-Form Evolution Equations

, 2016
Plasticity is governed by the evolution of, in general anisotropic, systems of dislocations. We seek to faithfully represent this evolution in terms of density-like variables which average over the discrete dislocation microstructure.
Monavari, Mehran, Sandfeld, Stefan, Zaiser, Michael   +2 more
core   +1 more source

Adaptive 4D‐Printed Vascular Stents With Low‐Temperature‐Activated and Intelligent Deployment

Advanced Functional Materials, EarlyView.
Microarchitected coronary artery stents were fabricated using a polycaprolactone (PCL)‐based shape memory polymer (SMP) composite via projection micro‐stereolithography (PµSL) 4D printing. By incorporating diethyl phthalate (DEP) as a plasticizer, the thermal transition temperature (Ttran) was modulated to about 37°C, enabling rapid and autonomous ...
Yannan Li, Yifan Pan, Chikahiro Imashiro, Chaolun Xu, Jianxian He, Jingao Xu, Kewei Song, Ze Zhang, Chen Gao, Junbo Jiang, Runhuai Yang, Kayo Hirose, Shinjiro Umezu   +12 more
wiley   +1 more source

Quantification of grain boundary effects on the geometrically necessary dislocation density evolution and strain hardening of polycrystalline Mg4Al using in situ tensile testing in scanning electron microscope and HR-EBSD

Journal of Magnesium and Alloys
In situ tensile testing in a scanning electron microscope (SEM) in conjunction with high-resolution electron backscatter diffraction (HR-EBSD) under load was used to characterize the evolution of geometrically necessary dislocation (GND) densities at ...
Eunji Song, Mohsen Taheri Andani, Amit Misra   +2 more
doaj   +1 more source

Plasticity of crystals and interfaces: From discrete dislocations to size-dependent continuum theory [PDF]

Theoretical and Applied Mechanics, 2010
In this communication, we summarize the current advances in size-dependent continuum plasticity of crystals, specifically, the rate-independent (quasistatic) formulation, on the basis of dislocation mechanics.
Mesarovic Sinisa Đ.
doaj   +1 more source

Defects in Crystalline Packings of Twisted Filament Bundles: I. Continuum Theory of Disclinations

, 2011
We develop the theory of the coupling between in-plane order and out-of-plane geometry in twisted, two-dimensionally ordered filament bundles based on the non-linear continuum elasticity theory of columnar materials.
Grason, Gregory M.
core   +1 more source

Length-scale effect due to periodic variation of geometrically necessary dislocation densities

International Journal of Plasticity, 2013
Abstract Strain gradient plasticity theories have been successful in predicting qualitative aspects of the length scale effect, most notably the increase in yield strength and hardness as the size of the deforming volume decreases. However new experimental methodologies enabled by recent developments of high spatial resolution diffraction methods in ...
Oeztop, Muin S., Niordson, Christian F., Kysar, Jeffrey W.   +2 more
openaire   +2 more sources

Toughening β‐Ga2O3 via Mechanically Seeded Dislocations

Advanced Functional Materials, EarlyView.
β‐Ga2O3 is promising for next‐generation semiconductors but its brittleness limits flexible and high‐precision applications. Here, mechanically seeded dislocations introduced by surface deformation improved damage tolerance in (001) β‐Ga2O3. Nanoindentation and characterization show dislocations suppress cleavage cracks by enabling stable plastic ...
Zanlin Cheng, Jiawen Zhang, Peng Gao, Guosong Zeng, Xufei Fang, Wenjun Lu   +5 more
wiley   +1 more source

Plastic dislocation and incompatibility density as indicators for residual stresses [PDF]

, 2019
Residual stresses in forming simulations are typically investigated by analyzing the remaining stress state after removing all external loadings. However, the generation of the stress state during forming remains unknown.
Landkammer, Philipp, Steinmann, Paul
core  

An algebraic description of screw dislocations in SC and BCC crystal lattices

, 2018
We give an algebraic description of screw dislocations in a crystal, especially simple cubic (SC) and body centered cubic (BCC) crystals, using free abelian groups and fibering structures.
Hamada, Hiroyasu, Matsutani, Shigeki, Nakagawa, Junichi, Saeki, Osamu, Uesaka, Masaaki   +4 more
core   +1 more source

Geometrically necessary dislocation density distributions in Ti–6Al–4V deformed in tension

Acta Materialia, 2011
Abstract We have used cross-correlation-based analysis of electron backscatter diffraction patterns to map lattice rotations in polycrystalline samples of Ti–6Al–4V before and after moderate (6%) tensile deformation. The sensitivity is improved compared to conventional Hough-based indexing and allows the density of geometrically necessary ...
Littlewood, P, Britton, T, Wilkinson, A
openaire   +1 more source