A Micromechanical Model of Additively Manufactured Aluminum Alloys

A micromechanical model is developed to predict the deformation behavior of additively manufactured aluminum alloys. Three-dimensional models of grain structures typical for different microregions of the melt pool are generated by the step-by-step packing method. A crystal plasticity-based constitutive model accounting for the elastic-plastic anisotropy of face-centered cubic crystals is employed to simulate the microscale deformation in an additively manufactured aluminum alloy under loading. The grain shape and texture effects on the plastic strain localization patterns are analyzed.

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Microstructure Refinement by Low-Temperature Ausforming in an Fe-Based Metastable High-Entropy Alloy

Metals ◽

10.3390/met11050742 ◽

2021 ◽

Vol 11 (5) ◽

pp. 742

Author(s):

Motomichi Koyama ◽

Takeaki Gondo ◽

Kaneaki Tsuzaki

Keyword(s):

Low Temperature ◽

Plastic Anisotropy ◽

High Entropy Alloy ◽

Face Centered Cubic ◽

High Entropy ◽

Microstructure Refinement ◽

Hexagonal Close Packed ◽

Solution Treated Condition ◽

Solution Treated ◽

Face Centered

The effects of ausforming in an Fe30Mn10Cr10Co high-entropy alloy on the microstructure, hardness, and plastic anisotropy were investigated. The alloy showed a dual-phase microstructure consisting of face-centered cubic (FCC) austenite and hexagonal close-packed (HCP) martensite in the as-solution-treated condition, and the finish temperature for the reverse transformation was below 200 °C. Therefore, low-temperature ausforming at 200 °C was achieved, which resulted in microstructure refinement and significantly increased the hardness. Furthermore, plasticity anisotropy, a common problem in HCP structures, was suppressed by the ausforming treatment. This, in turn, reduced the scatter of the hardness.

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Epitaxial Ni nanoparticles on CaF2(001), (110) and (111) surfaces studied by three-dimensional RHEED, GIXD and GISAXS reciprocal-space mapping techniques

Journal of Applied Crystallography ◽

10.1107/s160057671700512x ◽

2017 ◽

Vol 50 (3) ◽

pp. 830-839 ◽

Cited By ~ 4

Author(s):

S. M. Suturin ◽

V. V. Fedorov ◽

A. M. Korovin ◽

N. S. Sokolov ◽

A. V. Nashchekin ◽

...

Keyword(s):

Lattice Structure ◽

Three Dimensional ◽

Grazing Incidence ◽

High Energy ◽

Reciprocal Space ◽

Mapping Technique ◽

Face Centered Cubic ◽

X Ray ◽

Cubic Lattice ◽

Face Centered

The development of growth techniques aimed at the fabrication of nanoscale heterostructures with layers of ferroic 3dmetals on semiconductor substrates is very important for their potential usage in magnetic media recording applications. A structural study is presented of single-crystal nickel island ensembles grown epitaxially on top of CaF2/Si insulator-on-semiconductor heteroepitaxial substrates with (111), (110) and (001) fluorite surface orientations. The CaF2buffer layer in the studied multilayer system prevents the formation of nickel silicide, guides the nucleation of nickel islands and serves as an insulating layer in a potential tunneling spin injection device. The present study, employing both direct-space and reciprocal-space techniques, is a continuation of earlier research on ferromagnetic 3dtransition metals grown epitaxially on non-magnetic and magnetically ordered fluorides. It is demonstrated that arrays of stand-alone faceted nickel islands with a face-centered cubic lattice can be grown controllably on CaF2surfaces of (111), (110) and (001) orientations. The proposed two-stage nickel growth technique employs deposition of a thin seeding layer at low temperature followed by formation of the islands at high temperature. The application of an advanced three-dimensional mapping technique exploiting reflection high-energy electron diffraction (RHEED) has proved that the nickel islands tend to inherit the lattice orientation of the underlying fluorite layer, though they exhibit a certain amount of {111} twinning. As shown by scanning electron microscopy, grazing-incidence X-ray diffraction (GIXD) and grazing-incidence small-angle X-ray scattering (GISAXS), the islands are of similar shape, being faceted with {111} and {100} planes. The results obtained are compared with those from earlier studies of Co/CaF2epitaxial nanoparticles, with special attention paid to the peculiarities related to the differences in lattice structure of the deposited metals: the dual-phase hexagonal close-packed/face-centered cubic lattice structure of cobalt as opposed to the single-phase face-centered cubic lattice structure of nickel.

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Interactions between dislocations and three-dimensional annealing twins in face centered cubic metals

Computational Materials Science ◽

10.1016/j.commatsci.2019.02.024 ◽

2019 ◽

Vol 161 ◽

pp. 371-378 ◽

Cited By ~ 4

Author(s):

Yanxiang Liang ◽

Xiaofang Yang ◽

Mingyu Gong ◽

Guisen Liu ◽

Qing Liu ◽

...

Keyword(s):

Three Dimensional ◽

Face Centered Cubic ◽

Cubic Metals ◽

Annealing Twins ◽

Face Centered

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Electromagnetic Thermal Energy Transfer in Nanoparticle Assemblies Below Diffraction Limit

Journal of Thermal Science and Engineering Applications ◽

10.1115/1.4047631 ◽

2020 ◽

Vol 13 (2) ◽

Author(s):

Anil Yuksel ◽

Edward T. Yu ◽

Michael Cullinan ◽

Jayathi Murthy

Keyword(s):

Three Dimensional ◽

Close Packing ◽

Face Centered Cubic ◽

Copper Nanoparticle ◽

Colloidal Solutions ◽

Plasmonic Coupling ◽

Nanoparticle Assemblies ◽

Enhanced Absorption ◽

Face Centered ◽

Insight Into

Abstract Fabrication of micro- and nanoscale electronic components has become increasingly demanding due to device and interconnect scaling combined with advanced packaging and assembly for electronic, aerospace, and medical applications. Recent advances in additive manufacturing have made it possible to fabricate microscale, 3D interconnect structures but heat transfer during the fabrication process is one of the most important phenomena influencing the reliable manufacturing of these interconnect structures. In this study, optical absorption and scattering by three-dimensional (3D) nanoparticle packings are investigated to gain insight into micro/nano heat transport within the nanoparticles. Because drying of colloidal solutions creates different configurations of nanoparticles, the plasmonic coupling in three different copper nanoparticle packing configurations was investigated: simple cubic (SC), face-centered cubic (FCC), and hexagonal close packing (HCP). Single-scatter albedo (ω) was analyzed as a function of nanoparticle size, packing density, and configuration to assess effect for thermo-optical properties and plasmonic coupling of the Cu nanoparticles within the nanoparticle packings. This analysis provides insight into plasmonically enhanced absorption in copper nanoparticle particles and its consequences for laser heating of nanoparticle assemblies.

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An Extended Drucker Yield Criterion to Consider Tension–Compression Asymmetry and Anisotropy on Metallic Materials: Modeling and Verification

Metals ◽

10.3390/met10010020 ◽

2019 ◽

Vol 10 (1) ◽

pp. 20

Author(s):

Bingtao Tang ◽

Zhongmei Wang ◽

Ning Guo ◽

Qiaoling Wang ◽

Peixing Liu

Keyword(s):

Aluminum Alloys ◽

Yield Criterion ◽

Three Dimensional ◽

Yield Function ◽

Close Packing ◽

Bending Test ◽

Rolled Plate ◽

Face Centered Cubic ◽

Metallic Materials ◽

Stress Invariant

Pressure sensitive asymmetric Drucker yield criterion is developed to deal with pressure dependent sheet metals for instance steels and aluminum alloys. The sensitivity to pressure is conserved by introducing three-dimensional anisotropic parameters in the first stress invariant; while the third deviatoric stress invariant is remained in odd function form to consider the strength differential effect (SDE). To describe the flow stress directionalities of metallic materials, the Drucker yield function is extended using two transformation matrix consisting of anisotropic parameters. The proposed Drucker yield criterion is utilized to predict the anisotropic yield and plastic deformation of aluminum alloys with weak SDE: AA 2090-T3 with face-centered cubic (FCC) crystal systems and AA 2008-T4 with body-centered cubic (BCC) crystal systems as well as metals with strong SDE: Zirconium clock-rolled plate with hexagonal close packing (HCP) crystal systems. The comparison between the predicted anisotropic behavior and experimental results reveals that the extended anisotropic Drucker yield criterion can precisely model the anisotropy for FCC, BCC and HCP metals. The proposed function is implemented into ABAQUS VUMAT subroutines to describe the four-point bending test which is used to consider the effect of various yield functions and material orientations on deformation behavior. The obtained contours of the cross-section, strain components distribution and also the shift of neutral layer indicate that the extended Drucker yield function can well predict the final geometric configuration of the deformed Zirconium beam.

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Analysis of Voigt effects in dispersive properties for tunable three-dimensional face-centered-cubic magnetized plasma photonic crystals

Journal of Electromagnetic Waves and Applications ◽

10.1080/09205071.2013.805436 ◽

2013 ◽

Vol 27 (10) ◽

pp. 1276-1292 ◽

Cited By ~ 16

Author(s):

Hai-Feng Zhang ◽

Shao-Bin Liu ◽

Xiang-Kun Kong

Keyword(s):

Photonic Crystals ◽

Three Dimensional ◽

Magnetized Plasma ◽

Face Centered Cubic ◽

Plasma Photonic Crystals ◽

Face Centered ◽

Dimensional Face

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Structure and stacking order in crystals of asymmetric dumbbell-like colloids

Journal of Applied Crystallography ◽

10.1107/s1600576714028222 ◽

2015 ◽

Vol 48 (1) ◽

pp. 238-243 ◽

Cited By ~ 7

Author(s):

Antara Pal ◽

Janne-Mieke Meijer ◽

Joost R. Wolters ◽

Willem K. Kegel ◽

Andrei V. Petukhov

Keyword(s):

Crystalline Structure ◽

Diffuse Scattering ◽

Colloidal Particles ◽

Three Dimensional ◽

Stacking Faults ◽

Face Centered Cubic ◽

Hexagonal Close Packed ◽

Stacking Order ◽

X Ray Scattering ◽

Face Centered

The crystalline structure assembled out of charge-stabilized asymmetric dumbbell-like colloidal particles in ethyl alcohol by sedimentation has been probed using small-angle X-ray scattering with microradian resolution. The existence of plastic face-centered cubic crystals was inferred from the observed Bragg peaks. The presence of stacking faults and the mosaic structure of the sample lead to the appearance of diffuse scattering, forming Bragg scattering cylinders in the three-dimensional reciprocal space. The quality of the crystalline structure, as ascertained from a detailed analysis of the diffuse scattering intensity distribution, indicates the presence of only 1.5% of stacking faults between the hexagonal close-packed layers.

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SITE- AND BOND-DIFFUSION ON REGULAR LATTICES

International Journal of Modern Physics B ◽

10.1142/s0217979209053217 ◽

2009 ◽

Vol 23 (24) ◽

pp. 4943-4952

Author(s):

LASKO BASNARKOV ◽

VIKTOR URUMOV

Keyword(s):

Transition Probability ◽

Three Dimensional ◽

Diffusion Constant ◽

Single Step ◽

Face Centered Cubic ◽

Periodic Orbit Theory ◽

Regular Lattices ◽

Orbit Theory ◽

Face Centered ◽

Theoretical Results

We consider two types of motion, one with particle occupying only the sites on a given regular lattice and another when the bonds between neighboring lattice sites are displaced to the positions of the neighboring bonds. We refer to these models as site- and bond-diffusion. The latter is equivalent to site-diffusion on a lattice constructed from the middle points on each bond of the original lattice. The transition probability is assumed equal to all neighboring positions. The diffusion constant is obtained by periodic orbit theory for all Archimedean lattices, as well as some three-dimensional lattices (cubic, diamond, body centered cubic and face centered cubic lattice). Every single step of bond-motion is expressed through two site-motion steps. Analytic results for the diffusion constant for bond-diffusion for square, triangular and Kagomé lattice are also obtained. Kurtosis is calculated for site-diffusion on square and (4, 82)-lattice, to estimate the deviation of the distribution of displacements from the Gaussian. All theoretical results are verified with numerical simulation.

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