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Materials, Volume 6, Issue 8 (August 2013), Pages 3035-3675

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Open AccessArticle Broadband Luminescence in Rare Earth Doped Sr2SiS4: Relating Energy Levels of Ce3+ and Eu2+
Materials 2013, 6(8), 3663-3675; https://doi.org/10.3390/ma6083663
Received: 17 May 2013 / Revised: 17 July 2013 / Accepted: 13 August 2013 / Published: 21 August 2013
Cited by 9 | PDF Full-text (751 KB) | HTML Full-text | XML Full-text
Abstract
Sr2SiS4:Ce3+ is an efficient blue-emitting (460 nm) phosphor, excitable with light of wavelengths up to 420 nm. From the excitation spectrum, we construct the energy level scheme and use it to check the predictive power of the Dorenbos model, relating the positions of
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Sr2SiS4:Ce3+ is an efficient blue-emitting (460 nm) phosphor, excitable with light of wavelengths up to 420 nm. From the excitation spectrum, we construct the energy level scheme and use it to check the predictive power of the Dorenbos model, relating the positions of the Ce3+ energy levels with those of Eu2+ in the same host. For strontium thiosilicate, this method gives excellent results and allows us to determine which of two available crystallographic sites is occupied by cerium. We use the Dorenbos method for extracting information on the coordination of Ce3+ from the observed crystal field splitting. Full article
(This article belongs to the Special Issue Luminescent Materials 2013)
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Open AccessReview Progress in Titanium Metal Powder Injection Molding
Materials 2013, 6(8), 3641-3662; https://doi.org/10.3390/ma6083641
Received: 29 July 2013 / Revised: 8 August 2013 / Accepted: 9 August 2013 / Published: 20 August 2013
Cited by 38 | PDF Full-text (872 KB) | HTML Full-text | XML Full-text
Abstract
Metal powder injection molding is a shaping technology that has achieved solid scientific underpinnings. It is from this science base that recent progress has occurred in titanium powder injection molding. Much of the progress awaited development of the required particles with specific characteristics
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Metal powder injection molding is a shaping technology that has achieved solid scientific underpinnings. It is from this science base that recent progress has occurred in titanium powder injection molding. Much of the progress awaited development of the required particles with specific characteristics of particle size, particle shape, and purity. The production of titanium components by injection molding is stabilized by a good understanding of how each process variable impacts density and impurity level. As summarized here, recent research has isolated the four critical success factors in titanium metal powder injection molding (Ti-MIM) that must be simultaneously satisfied—density, purity, alloying, and microstructure. The critical role of density and impurities, and the inability to remove impurities with sintering, compels attention to starting Ti-MIM with high quality alloy powders. This article addresses the four critical success factors to rationalize Ti-MIM processing conditions to the requirements for demanding applications in aerospace and medical fields. Based on extensive research, a baseline process is identified and reported here with attention to linking mechanical properties to the four critical success factors. Full article
(This article belongs to the Special Issue Progress in Net-shaped PM (Powder Metallurgical) Parts)
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Open AccessArticle The Effect of a Rapid Heating Rate, Mechanical Vibration and Surfactant Chemistry on the Structure–Property Relationships of Epoxy/Clay Nanocomposites
Materials 2013, 6(8), 3624-3640; https://doi.org/10.3390/ma6083624
Received: 27 May 2013 / Revised: 6 August 2013 / Accepted: 9 August 2013 / Published: 20 August 2013
Cited by 6 | PDF Full-text (1086 KB) | HTML Full-text | XML Full-text
Abstract
The role of processing conditions and intercalant chemistry in montmorillonite clays on the dispersion, morphology and mechanical properties of two epoxy/clay nanocomposite systems was investigated in this paper. This work highlights the importance of employing complementary techniques (X-ray diffraction, small angle X-ray scattering,
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The role of processing conditions and intercalant chemistry in montmorillonite clays on the dispersion, morphology and mechanical properties of two epoxy/clay nanocomposite systems was investigated in this paper. This work highlights the importance of employing complementary techniques (X-ray diffraction, small angle X-ray scattering, optical microscopy and transmission electron microscopy) to correlate nanomorphology to macroscale properties. Materials were prepared using an out of autoclave manufacturing process equipped to generate rapid heating rates and mechanical vibration. The results suggested that the quaternary ammonium surfactant on C30B clay reacted with the epoxy during cure, while the primary ammonium surfactant (I.30E) catalysed the polymerisation reaction. These effects led to important differences in nanocomposite clay morphologies. The use of mechanical vibration at 4 Hz prior to matrix gelation was found to facilitate clay dispersion and to reduce the area fraction of I.30E clay agglomerates in addition to increasing flexural strength by over 40%. Full article
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Open AccessArticle Fabrication of Super-Hydrophobic Microchannels via Strain-Recovery Deformations of Polystyrene and Oxygen Reactive Ion Etch
Materials 2013, 6(8), 3610-3623; https://doi.org/10.3390/ma6083610
Received: 26 July 2013 / Revised: 13 August 2013 / Accepted: 14 August 2013 / Published: 19 August 2013
Cited by 8 | PDF Full-text (759 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
In this article, we report a simple approach to generate micropillars (whose top portions are covered by sub-micron wrinkles) on the inner surfaces of polystyrene (PS) microchannels, as well as on the top surface of the PS substrate, based on strain-recovery deformations of
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In this article, we report a simple approach to generate micropillars (whose top portions are covered by sub-micron wrinkles) on the inner surfaces of polystyrene (PS) microchannels, as well as on the top surface of the PS substrate, based on strain-recovery deformations of the PS and oxygen reactive ion etch (ORIE). Using this approach, two types of micropillar-covered microchannels are fabricated. Their widths range from 118 μm to 132 μm, depths vary from 40 μm to 44 μm, and the inclined angles of their sidewalls are from 53° to 64°. The micropillars enable these microchannels to have super-hydrophobic properties. The contact angles observed on the channel-structured surfaces are above 162°, and the tilt angles to make water drops roll off from these channel-structured substrates can be as small as 1°. Full article
(This article belongs to the Special Issue Smart Polymers and Polymeric Structures)
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Open AccessArticle Drift in Diffusion Gradients
Materials 2013, 6(8), 3598-3609; https://doi.org/10.3390/ma6083598
Received: 27 June 2013 / Revised: 23 July 2013 / Accepted: 13 August 2013 / Published: 19 August 2013
Cited by 10 | PDF Full-text (393 KB) | HTML Full-text | XML Full-text
Abstract
The longstanding problem of Brownian transport in a heterogeneous quasi one-dimensional medium with space-dependent self-diffusion coefficient is addressed in the overdamped (zero mass) limit. A satisfactory mesoscopic description is obtained in the Langevin equation formalism by introducing an appropriate drift term, which depends
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The longstanding problem of Brownian transport in a heterogeneous quasi one-dimensional medium with space-dependent self-diffusion coefficient is addressed in the overdamped (zero mass) limit. A satisfactory mesoscopic description is obtained in the Langevin equation formalism by introducing an appropriate drift term, which depends on the system macroscopic observables, namely the diffuser concentration and current. The drift term is related to the microscopic properties of the medium. The paradoxical existence of a finite drift at zero current suggests the possibility of designing a Maxwell demon operating between two equilibrium reservoirs at the same temperature. Full article
(This article belongs to the Special Issue Diffusion in Micropores and Mesopores 2013)
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Open AccessArticle Hydrothermal Growth of Vertically Aligned ZnO Nanorods Using a Biocomposite Seed Layer of ZnO Nanoparticles
Materials 2013, 6(8), 3584-3597; https://doi.org/10.3390/ma6083584
Received: 22 July 2013 / Revised: 24 July 2013 / Accepted: 8 August 2013 / Published: 19 August 2013
Cited by 45 | PDF Full-text (1673 KB) | HTML Full-text | XML Full-text
Abstract
Well aligned ZnO nanorods have been prepared by a low temperature aqueous chemical growth method, using a biocomposite seed layer of ZnO nanoparticles prepared in starch and cellulose bio polymers. The effect of different concentrations of biocomposite seed layer on the alignment of
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Well aligned ZnO nanorods have been prepared by a low temperature aqueous chemical growth method, using a biocomposite seed layer of ZnO nanoparticles prepared in starch and cellulose bio polymers. The effect of different concentrations of biocomposite seed layer on the alignment of ZnO nanorods has been investigated. ZnO nanorods grown on a gold-coated glass substrate have been characterized by X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM) techniques. These techniques have shown that the ZnO nanorods are well aligned and perpendicular to the substrate, and grown with a high density and uniformity on the substrate. Moreover, ZnO nanorods can be grown with an orientation along the c-axis of the substrate and exhibit a wurtzite crystal structure with a dominant (002) peak in an XRD spectrum and possessed a high crystal quality. A photoluminescence (PL) spectroscopy study of the ZnO nanorods has revealed a conventional near band edge ultraviolet emission, along with emission in the visible part of the electromagnetic spectrum due to defect emission. This study provides an alternative method for the fabrication of well aligned ZnO nanorods. This method can be helpful in improving the performance of devices where alignment plays a significant role. Full article
(This article belongs to the Section Biomaterials)
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Open AccessArticle Study of Lysozyme-Loaded Poly-L-Lactide (PLLA) Porous Microparticles in a Compressed CO2 Antisolvent Process
Materials 2013, 6(8), 3571-3583; https://doi.org/10.3390/ma6083571
Received: 5 May 2013 / Revised: 7 July 2013 / Accepted: 14 August 2013 / Published: 19 August 2013
Cited by 8 | PDF Full-text (1072 KB) | HTML Full-text | XML Full-text
Abstract
Lysozyme (LSZ)-loaded poly-L-lactide (PLLA) porous microparticles (PMs) were successfully prepared by a compressed CO2 antisolvent process in combination with a water-in-oil emulsion process using LSZ as a drug model and ammonium bicarbonate as a porogen. The effects of different drug loads (5.0%,
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Lysozyme (LSZ)-loaded poly-L-lactide (PLLA) porous microparticles (PMs) were successfully prepared by a compressed CO2 antisolvent process in combination with a water-in-oil emulsion process using LSZ as a drug model and ammonium bicarbonate as a porogen. The effects of different drug loads (5.0%, 7.5% and 10.0%) on the surface morphology, particle size, porosity, tapped density and drug release profile of the harvested PMs were investigated. The results show that an increase in the amount of LSZ added led to an increase in drug load (DL) but a decrease in encapsulation efficiency. The resulting LSZ-loaded PLLA PMs (LSZ-PLLA PMs) exhibited a porous and uneven morphology, with a density less than 0.1 g·cm−3, a geometric mean diameter of 16.9–18.8 μm, an aerodynamic diameter less than 2.8 μm, a fine particle fraction (FPF) of 59.2%–66.8%, and a porosity of 78.2%–86.3%. According to the results of differential scanning calorimetry, the addition of LSZ improved the thermal stability of PLLA. The Fourier transform infrared spectroscopy analysis and circular dichroism spectroscopy measurement reveal that no significant changes occurred in the molecular structures of LSZ during the fabrication process, which was further confirmed by the evaluation of enzyme activity of LSZ. It is demonstrated that the emulsion-combined precipitation with compressed antisolvent (PCA) process could be a promising technology to develop biomacromolecular drug-loaded inhalable carrier for pulmonary drug delivery. Full article
(This article belongs to the Section Biomaterials)
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Open AccessArticle Periodic Mesoporous Organosilica Functionalized with Sulfonic Acid Groups as Acid Catalyst for Glycerol Acetylation
Materials 2013, 6(8), 3556-3570; https://doi.org/10.3390/ma6083556
Received: 11 July 2013 / Revised: 1 August 2013 / Accepted: 13 August 2013 / Published: 16 August 2013
Cited by 9 | PDF Full-text (593 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
A Periodic Mesoporous Organosilica (PMO) functionalized with sulfonic acid groups has been successfully synthesized via a sequence of post-synthetic modification steps of a trans-ethenylene bridged PMO material. The double bond is functionalized via a bromination and subsequent substitution obtaining a thiol functionality.
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A Periodic Mesoporous Organosilica (PMO) functionalized with sulfonic acid groups has been successfully synthesized via a sequence of post-synthetic modification steps of a trans-ethenylene bridged PMO material. The double bond is functionalized via a bromination and subsequent substitution obtaining a thiol functionality. This is followed by an oxidation towards a sulfonic acid group. After full characterization, the solid acid catalyst is used in the acetylation of glycerol. The catalytic reactivity and reusability of the sulfonic acid modified PMO material is investigated. The catalyst showed a catalytic activity and kinetics that are comparable with the commercially available resin, Amberlyst-15, and furthermore our catalyst can be recycled for several subsequent catalytic runs and retains its catalytic activity. Full article
(This article belongs to the Section Porous Materials)
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Open AccessArticle Synthesis, Structural Characterization, and Antitumor Activity of a Ca(II) Coordination Polymer Based on 1,6-Naphthalenedisulfonate and 4,4′-Bipyridyl
Materials 2013, 6(8), 3547-3555; https://doi.org/10.3390/ma6083547
Received: 27 June 2013 / Revised: 12 July 2013 / Accepted: 7 August 2013 / Published: 16 August 2013
Cited by 22 | PDF Full-text (343 KB) | HTML Full-text | XML Full-text
Abstract
A novel Ca(II) coordination polymer, [CaL(4,4′-bipyridyl)(H2O)4]n (L = 1,6-naphthalenedisulfonate), was synthesized by reaction of calcium perchlorate with 1,6-naphthalenedisulfonic acid disodium salt and 4,4′-bipyridyl in CH3CH2OH/H2O. It was characterized by elemental analysis, IR,
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A novel Ca(II) coordination polymer, [CaL(4,4′-bipyridyl)(H2O)4]n (L = 1,6-naphthalenedisulfonate), was synthesized by reaction of calcium perchlorate with 1,6-naphthalenedisulfonic acid disodium salt and 4,4′-bipyridyl in CH3CH2OH/H2O. It was characterized by elemental analysis, IR, molar conductivity and thermogravimetric analysis. X-ray crystallography reveals that the Ca(II) coordination polymer belongs to the orthorhombic system, with space group P212121. The geometry of the Ca(II) ion is a distorted CaNO6 pengonal bipyramid, arising from its coordination by four water molecules, one nitrogen atom of 4,4′-bipyridyl molecule, and two oxygen atoms from two L ligands. The complex molecules form a helical chain by self-assembly. The antitumor activity of 1,6-naphthalenedisulfonic acid disodium salt and the Ca(II) coordination polymer against human hepatoma smmc-7721 cell line and human lung adenocarcinoma A549 cell line reveals that the Ca(II) coordination polymer inhibits cell growth of human lung adenocarcinoma A549 cell line with IC50 value of 27 μg/mL, and is more resistive to human lung adenocarcinoma A549 cell line as compared to 1,6-naphthalenedisulfonic acid disodium salt. Full article
(This article belongs to the Section Biomaterials)
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Open AccessArticle The Influence of Phase Change Materials on the Properties of Self-Compacting Concrete
Materials 2013, 6(8), 3530-3546; https://doi.org/10.3390/ma6083530
Received: 14 June 2013 / Revised: 12 July 2013 / Accepted: 5 August 2013 / Published: 15 August 2013
Cited by 15 | PDF Full-text (592 KB) | HTML Full-text | XML Full-text
Abstract
The aim of this paper is to research new thermally-efficient concrete walls, analyzing the mechanical behavior of a self-compacting concrete to manufacture an uncoated solid structural panel, with the incorporation of a micro-encapsulated phase change material as additive. Different dosages are tested and
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The aim of this paper is to research new thermally-efficient concrete walls, analyzing the mechanical behavior of a self-compacting concrete to manufacture an uncoated solid structural panel, with the incorporation of a micro-encapsulated phase change material as additive. Different dosages are tested and mechanical properties of the product obtained from the molding of concrete specimens are evaluated, testing mechanical compressive strength, slump flow, and density. The results reveal the optimum percentage of additive in the mixture that enables compliance with the technical specifications required by the product to be manufactured. A test is also performed for measuring the thermal conductivity for the optimal sample obtained and it evidences the reduction thereof. Full article
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Open AccessArticle Small-Scale Morphological Features on a Solid Surface Processed by High-Pressure Abrasive Water Jet
Materials 2013, 6(8), 3514-3529; https://doi.org/10.3390/ma6083514
Received: 27 May 2013 / Revised: 29 July 2013 / Accepted: 7 August 2013 / Published: 14 August 2013
Cited by 4 | PDF Full-text (1334 KB) | HTML Full-text | XML Full-text
Abstract
Being subjected to a high-pressure abrasive water jet, solid samples will experience an essential variation of both internal stress and physical characteristics, which is closely associated with the kinetic energy attached to the abrasive particles involved in the jet stream. Here, experiments were
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Being subjected to a high-pressure abrasive water jet, solid samples will experience an essential variation of both internal stress and physical characteristics, which is closely associated with the kinetic energy attached to the abrasive particles involved in the jet stream. Here, experiments were performed, with particular emphasis being placed on the kinetic energy attenuation and turbulent features in the jet stream. At jet pressure of 260 MPa, mean velocity and root-mean-square (RMS) velocity on two jet-stream sections were acquired by utilizing the phase Doppler anemometry (PDA) technique. A jet-cutting experiment was then carried out with Al-Mg alloy samples being cut by an abrasive water jet. Morphological features and roughness on the cut surface were quantitatively examined through scanning electron microscopy (SEM) and optical profiling techniques. The results indicate that the high-pressure water jet is characterized by remarkably high mean flow velocities and distinct velocity fluctuations. Those irregular pits and grooves on the cut surfaces indicate both the energy attenuation and the development of radial velocity components in the jet stream. When the sample is positioned with different distances from the nozzle outlet, the obtained quantitative surface roughness varies accordingly. A descriptive model highlighting the behaviors of abrasive particles in jet-cutting process is established in light of the experimental results and correlation analysis. Full article
(This article belongs to the Section Manufacturing Processes and Systems)
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Open AccessArticle Effects on the Thermo-Mechanical and Crystallinity Properties of Nylon 6,6 Electrospun Fibres Reinforced with One Dimensional (1D) and Two Dimensional (2D) Carbon
Materials 2013, 6(8), 3494-3513; https://doi.org/10.3390/ma6083494
Received: 30 April 2013 / Revised: 30 July 2013 / Accepted: 1 August 2013 / Published: 14 August 2013
Cited by 20 | PDF Full-text (1994 KB) | HTML Full-text | XML Full-text
Abstract
Electrospun one dimensional (1D) and two dimensional (2D) carbon based polymer nanocomposites are studied in order to determine the effect provided by the two differently structured nanofillers on crystallinity and thermo-mechanical properties of the nanofibres. The nanomaterials studied are pristine carbon nanotubes, oxidised
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Electrospun one dimensional (1D) and two dimensional (2D) carbon based polymer nanocomposites are studied in order to determine the effect provided by the two differently structured nanofillers on crystallinity and thermo-mechanical properties of the nanofibres. The nanomaterials studied are pristine carbon nanotubes, oxidised carbon nanotubes, reduced graphene oxide and graphene oxide. Functional groups associated with the order structure of the polymers are analysed by infrared and Raman spectroscopies; the morphology is studied by scanning electron microscopy and the crystallinity properties are investigated by differential scanning calorimetry and X-ray diffraction. Differences in crystallisation behaviour between 1D and 2D carbon based nanofibres are shown by their crystallinity degree and their crystal sizes. The nanocomposite crystal sizes perpendicular to the plane (100) decrease with nanofiller content in all cases. The crystallinity trend and crystal sizes are in accordance with storage modulus response. The results also suggest that functionalisation favours interfacial bonding and dispersion of the nanomaterials within the polymer matrix. As a consequence the number of nucleating sites increases which in turn decreases the crystal size in the nanocomposites. These features explain the improved thermo-mechanical properties in the nanocomposites. Full article
(This article belongs to the Special Issue Carbon Nanotubes)
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Open AccessArticle Study of Radio Frequency Plasma Treatment of PVDF Film Using Ar, O2 and (Ar + O2) Gases for Improved Polypyrrole Adhesion
Materials 2013, 6(8), 3482-3493; https://doi.org/10.3390/ma6083482
Received: 3 June 2013 / Revised: 31 July 2013 / Accepted: 1 August 2013 / Published: 13 August 2013
Cited by 11 | PDF Full-text (809 KB) | HTML Full-text | XML Full-text
Abstract
Improvement of the binding of polypyrrole with PVDF (polyvinylidene fluoride) thin film using low pressure plasma was studied. The effects of various plasma gases i.e., Ar, O2 and Ar + O2 gases on surface roughness, surface chemistry and hydrophilicity
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Improvement of the binding of polypyrrole with PVDF (polyvinylidene fluoride) thin film using low pressure plasma was studied. The effects of various plasma gases i.e., Ar, O2 and Ar + O2 gases on surface roughness, surface chemistry and hydrophilicity were noted. The topographical change of the PVDF film was observed by means of scanning electron microscopy and chemical changes by X-ray photoelectron spectroscopy, with adhesion of polypyrrole (PPy) by abrasion tests and sheet resistance measurements. Results showed that the increase in roughness and surface functionalization by oxygen functional groups contributed to improved adhesion and Ar + O2 plasma gave better adhesion. Full article
(This article belongs to the Special Issue Advances in Surface Coatings)
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Open AccessArticle Cyclic Deformation of Ultra-Fine Grained Commercial Purity Aluminum Processed by Accumulative Roll-Bonding
Materials 2013, 6(8), 3469-3481; https://doi.org/10.3390/ma6083469
Received: 21 May 2013 / Revised: 29 July 2013 / Accepted: 1 August 2013 / Published: 13 August 2013
Cited by 2 | PDF Full-text (3177 KB) | HTML Full-text | XML Full-text
Abstract
Accumulative Roll-Bonding (ARB) is one of the more recently developed techniques capable of producing bulk ultra-fine grained (ufg) metals. There are still many aspects of the behavior of ufg metals that lacks an in-depth understanding, such as a generalized view of the factors
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Accumulative Roll-Bonding (ARB) is one of the more recently developed techniques capable of producing bulk ultra-fine grained (ufg) metals. There are still many aspects of the behavior of ufg metals that lacks an in-depth understanding, such as a generalized view of the factors that govern the cyclic deformation mechanism(s). This study aims to advance the understanding of the cyclic deformation behavior of ufg metals through the systematic investigation of ARB processed aluminum upon cyclic loading. It was found that the cyclic softening response often reported for ufg metals is largely influenced by the microstructure stability as the cyclic softening response is facilitated by grain coarsening which becomes inhibited with highly stable microstructure. On one hand, shear bands resembling braids of dislocations trespassing multiple grains have been observed to operate for the accommodation of the imposed cyclic strain in cases where grain coarsening is largely restricted. On the other hand, it was found that the microstructure stability can be overcome at higher applied cyclic plastic strain levels, leading to grain coarsening and thus a cyclic softening response. The findings in this study have further confirmed that the cyclic softening behavior found in many ufg metals, which may be detrimental in practical applications, can be inhibited by improvements in the microstructure stability. Full article
(This article belongs to the Section Structure Analysis and Characterization)
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Open AccessArticle Manufacturing and Characterization of 18Ni Marage 300 Lattice Components by Selective Laser Melting
Materials 2013, 6(8), 3451-3468; https://doi.org/10.3390/ma6083451
Received: 7 May 2013 / Revised: 18 July 2013 / Accepted: 6 August 2013 / Published: 13 August 2013
Cited by 11 | PDF Full-text (1504 KB) | HTML Full-text | XML Full-text
Abstract
The spreading use of cellular structures brings the need to speed up manufacturing processes without deteriorating mechanical properties. By using Selective Laser Melting (SLM) to produce cellular structures, the designer has total freedom in defining part geometry and manufacturing is simplified. The paper
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The spreading use of cellular structures brings the need to speed up manufacturing processes without deteriorating mechanical properties. By using Selective Laser Melting (SLM) to produce cellular structures, the designer has total freedom in defining part geometry and manufacturing is simplified. The paper investigates the suitability of Selective Laser Melting for manufacturing steel cellular lattice structures with characteristic dimensions in the micrometer range. Alternative lattice topologies including reinforcing bars in the vertical direction also are considered. The selected lattice structure topology is shown to be superior over other lattice structure designs considered in literature. Compression tests are carried out in order to evaluate mechanical strength of lattice strut specimens made via SLM. Compressive behavior of samples also is simulated by finite element analysis and numerical results are compared with experimental data in order to assess the constitutive behavior of the lattice structure designs considered in this study. Experimental data show that it is possible to build samples of relative density in the 0.2456–0.4367 range. Compressive strength changes almost linearly with respect to relative density, which in turns depends linearly on the number of vertical reinforces. Specific strength increases with cell and strut edge size. Numerical simulations confirm the plastic nature of the instability phenomena that leads the cellular structures to collapse under compression loading. Full article
(This article belongs to the Section Manufacturing Processes and Systems)
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