Configuration Optimization Design of Ti6Al4V Lattice Structure Formed by SLM

Previous studies have revealed the influence of various lattice structures on the material density and mechanical properties. However, the majority of the topologies that are considered as study objects directly refer to metal/non-crystal lattice cell configurations. Therefore, this paper proposes a configuration generation approach for generating a lattice structure, which can obtain a lattice configuration that enjoys the advantages of both ultra-low weight and favorable mechanical properties. Based on this approach, a new type of face-centered cubic lattice (all face-centered cubic, AFCC) structure with comprehensively optimal properties in terms of mass and mechanical properties is obtained. The experimental samples are formed with Ti6Al4V by the selective laser melting (SLM) method. Quasi-static uniaxial compression performance experiments and finite element analysis (FEA) are conducted on an AFCC structure and the control group body-centered cubic (BCC) structure. The results demonstrates that our optimized AFCC lattice structure is superior to the BCC structure, with elastic modulus and yield limit increases of 143% and 120%, respectively. For the same degree of deformation, the energy absorbed increases approximately 2.4 times. The AFCC demonstrates significant advantages in terms of its mechanical properties and anti-explosion impact resistance while maintaining favorable ultra-low weight, which validates the hypothesis that the proposed configuration generation approach can provide guidance for the design and further research on ultra-light lattice structures in related fields.

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Ti-V-C-Based Alloy with a FCC Lattice Structure for Hydrogen Storage

Molecules ◽

10.3390/molecules24030552 ◽

2019 ◽

Vol 24 (3) ◽

pp. 552

Author(s):

Bo Li ◽

Liqing He ◽

Jianding Li ◽

Hai-Wen Li ◽

Zhouguang Lu ◽

...

Keyword(s):

Hydrogen Storage ◽

Room Temperature ◽

Lattice Structure ◽

Activation Process ◽

Face Centered Cubic ◽

Hydrogen Storage Materials ◽

Fcc Lattice ◽

Bcc Structure ◽

Face Centered ◽

Fcc Structure

Here we report a Ti50V50-10 wt.% C alloy with a unique lattice and microstructure for hydrogen storage development. Different from a traditionally synthesized Ti50V50 alloy prepared by a melting method and having a body-centered cubic (BCC) structure, this Ti50V50-C alloy synthesized by a mechanical alloying method is with a face-centered cubic (FCC) structure (space group: Fm-3m No. 225). The crystalline size is 60 nm. This alloy may directly absorb hydrogen near room temperature without any activation process. Mechanisms of the good kinetics from lattice and microstructure aspects were discussed. Findings reported here may indicate a new possibility in the development of future hydrogen storage materials.

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Novel Co-Cu-Based Immiscible Medium-Entropy Alloys with Promising Mechanical Properties

Metals ◽

10.3390/met11020238 ◽

2021 ◽

Vol 11 (2) ◽

pp. 238

Author(s):

Sujung Son ◽

Jongun Moon ◽

Hyeonseok Kwon ◽

Peyman Asghari Rad ◽

Hidemi Kato ◽

...

Keyword(s):

Mechanical Properties ◽

Binary System ◽

Design Methodology ◽

Miscibility Gap ◽

Face Centered Cubic ◽

Solid Solution Strengthening ◽

Solution Strengthening ◽

Face Centered ◽

Strength And Ductility ◽

Cobalt Copper

New AlxCo50−xCu50−xMnx (x = 2.5, 10, and 15 atomic %, at%) immiscible medium-entropy alloys (IMMEAs) were designed based on the cobalt-copper binary system. Aluminum, a strong B2 phase former, was added to enhance yield strength and ultimate tensile strength, while manganese was added for additional solid solution strengthening. In this work, the microstructural evolution and mechanical properties of the designed Al-Co-Cu-Mn system are examined. The alloys exhibit phase separation into dual face-centered cubic (FCC) phases due to the miscibility gap of the cobalt-copper binary system with the formation of CoAl-rich B2 phases. The hard B2 phases significantly contribute to the strength of the alloys, whereas the dual FCC phases contribute to elongation mitigating brittle fracture. Consequently, analysis of the Al-Co-Cu-Mn B2-strengthened IMMEAs suggest that the new alloy design methodology results in a good combination of strength and ductility.

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Effect of Sm Doping on the Microstructure, Mechanical Properties and Shape Memory Effect of Cu-13.0Al-4.0Ni Alloy

Materials ◽

10.3390/ma14144007 ◽

2021 ◽

Vol 14 (14) ◽

pp. 4007

Author(s):

Qimeng Zhang ◽

Bo Cui ◽

Bin Sun ◽

Xin Zhang ◽

Zhizhong Dong ◽

...

Keyword(s):

Mechanical Properties ◽

Shape Memory ◽

Shape Memory Effect ◽

Memory Effect ◽

Strengthening Effect ◽

Face Centered Cubic ◽

Compressive Fracture ◽

Fine Grain ◽

Fine Grain Strengthening ◽

Face Centered

The effects of rare earth element Sm on the microstructure, mechanical properties, and shape memory effect of the high temperature shape memory alloy, Cu-13.0Al-4.0Ni-xSm (x = 0, 0.2 and 0.5) (wt.%), are studied in this work. The results show that the Sm addition reduces the grain size of the Cu-13.0Al-4.0Ni alloy from millimeters to hundreds of microns. The microstructure of the Cu-13.0Al-4.0Ni-xSm alloys are composed of 18R and a face-centered cubic Sm-rich phase at room temperature. In addition, because the addition of the Sm element enhances the fine-grain strengthening effect, the mechanical properties and the shape memory effect of the Cu-13.0Al-4.0Ni alloy were greatly improved. When x = 0.5, the compressive fracture stress and the compressive fracture strain increased from 580 MPa, 10.5% to 1021 MPa, 14.8%, respectively. When the pre-strain is 10%, a reversible strain of 6.3% can be obtained for the Cu-13.0Al-4.0Ni-0.2Sm alloy.

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Development of Novel Lightweight Al-Rich Quinary Medium-Entropy Alloys with High Strength and Ductility

Materials ◽

10.3390/ma14154223 ◽

2021 ◽

Vol 14 (15) ◽

pp. 4223

Author(s):

Po-Sung Chen ◽

Yu-Chin Liao ◽

Yen-Ting Lin ◽

Pei-Hua Tsai ◽

Jason S. C. Jang ◽

...

Keyword(s):

Mechanical Properties ◽

Compressive Strength ◽

Compressive Strain ◽

High Strength ◽

Fine Tuning ◽

Face Centered Cubic ◽

Transportation Industry ◽

High Entropy ◽

Good Potential ◽

Face Centered

Most high-entropy alloys and medium-entropy alloys (MEAs) possess outstanding mechanical properties. In this study, a series of lightweight nonequiatomic Al50–Ti–Cr–Mn–V MEAs with a dual phase were produced through arc melting and drop casting. These cast alloys were composed of body-centered cubic and face-centered cubic phases. The density of all investigated MEAs was less than 5 g/cm3 in order to meet energy and transportation industry requirements. The effect of each element on the microstructure evolution and mechanical properties of these MEAs was investigated. All the MEAs demonstrated outstanding compressive strength, with no fractures observed after a compressive strain of 20%. Following the fine-tuning of the alloy composition, the Al50Ti20Cr10Mn15V5 MEA exhibited the most compressive strength (~1800 MPa) and ductility (~34%). A significant improvement in the mechanical compressive properties was achieved (strength of ~2000 MPa, strain of ~40%) after annealing (at 1000 °C for 0.5 h) and oil-quenching. With its extremely high specific compressive strength (452 MPa·g/cm3) and ductility, the lightweight Al50Ti20Cr10Mn15V5 MEA demonstrates good potential for energy or transportation applications in the future.

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Effects of Different Contents of Each Component on the Structural Stability and Mechanical Properties of Co-Cr-Fe-Ni High-Entropy Alloys

Applied Sciences ◽

10.3390/app11062832 ◽

2021 ◽

Vol 11 (6) ◽

pp. 2832

Author(s):

Haibo Liu ◽

Cunlin Xin ◽

Lei Liu ◽

Chunqiang Zhuang

Keyword(s):

Mechanical Properties ◽

Structural Stability ◽

High Entropy Alloys ◽

Face Centered Cubic ◽

Obvious Effect ◽

High Entropy ◽

Precise Control ◽

Component Content ◽

Face Centered ◽

And Performance

The structural stability of high-entropy alloys (HEAs) is closely related to their mechanical properties. The precise control of the component content is a key step toward understanding their structural stability and further determining their mechanical properties. In this study, first-principle calculations were performed to investigate the effects of different contents of each component on the structural stability and mechanical properties of Co-Cr-Fe-Ni HEAs based on the supercell model. Co-Cr-Fe-Ni HEAs were constructed based on a single face-centered cubic (FCC) solid solution. Elemental components have a clear effect on their structure and performance; the Cr and Fe elements have an obvious effect on the structural stability and equilibrium lattice constant, respectively. The Ni elements have an obvious effect on stiffness. The Pugh ratios indicate that Cr and Ni addition may increase ductility, whereas Co and Fe addition may decrease it. With increasing Co and Fe contents or decreasing Cr and Ni contents, the structural stability and stiffness of Co-Cr-Fe-Ni HEAs are improved. The structural stability and mechanical properties may be related to the strength of the metallic bonding and covalent bonding inside Co-Cr-Fe-Ni HEAs, which, in turn, is determined by the change in element content. Our results provide the underlying insights needed to guide the optimization of Co-Cr-Fe-Ni HEAs with excellent mechanical properties.

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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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Dynamic Loading of Lattice Structure Made by Selective Laser Melting-Numerical Model with Substitution of Geometrical Imperfections

Materials ◽

10.3390/ma11112129 ◽

2018 ◽

Vol 11 (11) ◽

pp. 2129 ◽

Cited By ~ 7

Author(s):

Radek Vrána ◽

Ondřej Červinek ◽

Pavel Maňas ◽

Daniel Koutný ◽

David Paloušek

Keyword(s):

Mechanical Properties ◽

Numerical Model ◽

Cross Section ◽

Lattice Structure ◽

Low Velocity Impact ◽

Lattice Structures ◽

Laser Melting ◽

Low Velocity ◽

Velocity Impact ◽

Geometrical Imperfections

Selective laser melting (SLM) is an additive technology that allows for the production of precisely designed complex structures for energy absorbing applications from a wide range of metallic materials. Geometrical imperfections of the SLM fabricated lattice structures, which form one of the many thin struts, can lead to a great difference in prediction of their behavior. This article deals with the prediction of lattice structure mechanical properties under dynamic loading using finite element method (FEA) with inclusion of geometrical imperfections of the SLM process. Such properties are necessary to know especially for the application of SLM fabricated lattice structures in automotive or aerospace industries. Four types of specimens from AlSi10Mg alloy powder material were manufactured using SLM for quasi-static mechanical testing and determination of lattice structure mechanical properties for the FEA material model, for optical measurement of geometrical accuracy, and for low-velocity impact testing using the impact tester with a flat indenter. Geometries of struts with elliptical and circular cross-sections were identified and tested using FEA. The results showed that, in the case of elliptical cross-section, a significantly better match was found (2% error in the Fmax) with the low-velocity impact experiments during the whole deformation process compared to the circular cross-section. The FEA numerical model will be used for future testing of geometry changes and its effect on mechanical properties.

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Generalization of the Unified Analytic Melt-Shear Model to Multi-Phase Materials: Molybdenum as an Example

Crystals ◽

10.3390/cryst9020086 ◽

2019 ◽

Vol 9 (2) ◽

pp. 86 ◽

Cited By ~ 2

Author(s):

Leonid Burakovsky ◽

Darby Luscher ◽

Dean Preston ◽

Sky Sjue ◽

Diane Vaughan

Keyword(s):

Shear Modulus ◽

Solid Phase ◽

Model Parameters ◽

Quantum Molecular Dynamics ◽

Face Centered Cubic ◽

Shear Model ◽

Bcc Structure ◽

Face Centered ◽

Multi Phase ◽

Theoretical Results

The unified analytic melt-shear model that we introduced a decade ago is generalized to multi-phase materials. A new scheme for calculating the values of the model parameters for both the cold ( T = 0 ) shear modulus ( G ) and the melting temperature at all densities ( ρ ) is developed. The generalized melt-shear model is applied to molybdenum, a multi-phase material with a body-centered cubic (bcc) structure at low ρ which loses its dynamical stability with increasing pressure (P) and is therefore replaced by another (dynamically stable) solid structure at high ρ . One of the candidates for the high- ρ structure of Mo is face-centered cubic (fcc). The model is compared to (i) our ab initio results on the cold shear modulus of both bcc-Mo and fcc-Mo as a function of ρ , and (ii) the available theoretical results on the melting of bcc-Mo and our own quantum molecular dynamics (QMD) simulations of one melting point of fcc-Mo. Our generalized model of G ( ρ , T ) is used to calculate the shear modulus of bcc-Mo along its principal Hugoniot. It predicts that G of bcc-Mo increases with P up to ∼240 GPa and then decreases at higher P. This behavior is intrinsic to bcc-Mo and does not require the introduction of another solid phase such as Phase II suggested by Errandonea et al. Generalized melt-shear models for Ta and W also predict an increase in G followed by a decrease along the principal Hugoniot, hence this behavior may be typical for transition metals with ambient bcc structure that dynamically destabilize at high P. Thus, we concur with the conclusion reached in several recent papers (Nguyen et al., Zhang et al., Wang et al.) that no solid-solid phase transition can be definitively inferred on the basis of sound velocity data from shock experiments on Mo. Finally, our QMD simulations support the validity of the phase diagram of Mo suggested by Zeng et al.

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Analytical model of the elastic behavior of a modified face-centered cubic lattice structure

Journal of the Mechanical Behavior of Biomedical Materials ◽

10.1016/j.jmbbm.2019.05.043 ◽

2019 ◽

Vol 98 ◽

pp. 357-368 ◽

Cited By ~ 5

Author(s):

Markel Alaña ◽

Aitziber Lopez-Arancibia ◽

Ainara Pradera-Mallabiabarrena ◽

Sergio Ruiz de Galarreta

Keyword(s):

Analytical Model ◽

Lattice Structure ◽

Elastic Behavior ◽

Face Centered Cubic ◽

Cubic Lattice ◽

Face Centered

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INFLUENCE OF PRESSURE AND ATOMIC CONCENTRATION ON STRUCTURE AND MECHANICAL PROPERTIES OF CuNi ALLOY BY MOLECULAR DYNAMICS SIMULATION

Journal of Science Natural Science ◽

10.18173/2354-1059.2020-0029 ◽

2020 ◽

Vol 65 (6) ◽

pp. 54-60

Author(s):

Thao Nguyen Thi ◽

Hang Trinh Thi Thu

Keyword(s):

Mechanical Properties ◽

Dynamics Simulation ◽

Embedded Atom Method ◽

Face Centered Cubic ◽

Atomic Concentration ◽

Common Neighbor ◽

Hexagonal Close Packed ◽

Embedded Atom ◽

The Common ◽

Face Centered

The structure and mechanical properties of Cu80Ni20 and Cu50Ni50 alloys with the size of 4000 atoms have been investigated using molecular dynamic (MD) simulation. The interactions between atoms of the system were calculated by the Sutton-Chen type of embedded atom method. Using a cooling rate of 0.01 K\ps, we find that both Ni and Cu atoms are crystallized into face centered cubic (fcc) and the hexagonal close packed (hcp) phases when the sample was cooled down to 300 K. The atomic concentration of CuNi alloy samples have a different effect on this crystallization. The transformation to the crystalline phase is analyzed through the Common Neighbor Analysis (CNA) methods. Furthermore, we focus on the dependence of the mechanical properties of CuNi alloy on pressure and atomic concentration

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