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1 – 10 of over 15000A. Vivek, K. Shambavi and Zachariah C. Alex
This paper aims to focus on research work related to metamaterial-based sensors for material characterization that have been developed for past ten years. A decade of research on…
Abstract
Purpose
This paper aims to focus on research work related to metamaterial-based sensors for material characterization that have been developed for past ten years. A decade of research on metamaterial for sensing application has led to the advancement of compact and improved sensors.
Design/methodology/approach
In this study, relevant research papers on metamaterial sensors for material characterization published in reputed journals during the period 2007-2018 were reviewed, particularly focusing on shape, size and nature of materials characterized. Each sensor with its design and performance parameters have been summarized and discussed here.
Findings
As metamaterial structures are excited by electromagnetic wave interaction, sensing application throughout electromagnetic spectrum is possible. Recent advancement in fabrication techniques and improvement in metamaterial structures have led to the development of compact, label free and reversible sensors with high sensitivity.
Originality/value
The paper provides useful information on the development of metamaterial sensors for material characterization.
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James Elgy, Paul D. Ledger, John L. Davidson, Toykan Özdeğer and Anthony J. Peyton
The ability to characterise highly conducting objects, that may also be highly magnetic, by the complex symmetric rank–2 magnetic polarizability tensor (MPT) is important for…
Abstract
Purpose
The ability to characterise highly conducting objects, that may also be highly magnetic, by the complex symmetric rank–2 magnetic polarizability tensor (MPT) is important for metal detection applications including discriminating between threat and non-threat objects in security screening, identifying unexploded anti-personnel landmines and ordnance and identifying metals of high commercial value in scrap sorting. Many everyday non-threat items have both a large electrical conductivity and a magnetic behaviour, which, for sufficiently weak fields and the frequencies of interest, can be modelled by a high relative magnetic permeability. This paper aims to discuss the aforementioned idea.
Design/methodology/approach
The numerical simulation of the MPT for everyday non-threat highly conducting magnetic objects over a broad range of frequencies is challenging due to the resulting thin skin depths. The authors address this by employing higher order edge finite element discretisations based on unstructured meshes of tetrahedral elements with the addition of thin layers of prismatic elements. Furthermore, computer aided design (CAD) geometrical models of the non-threat and threat object are often not available and, instead, the authors extract the geometrical features of an object from an imaging procedure.
Findings
The authors obtain accurate numerical MPT characterisations that are in close agreement with experimental measurements for realistic physical objects. The assessment of uncertainty shows the impact of geometrical and material parameter uncertainties on the computational results.
Originality/value
The authors present novel computations and measurements of MPT characterisations of realistic objects made of magnetic materials. A novel assessment of uncertainty in the numerical predictions of MPT characterisations for uncertain geometry and material parameters is included.
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Kunal Kumar Singh, Santosh Kumar Mahto and Rashmi Sinha
This paper aims to concentrate on research that has been conducted in the previous decade on metamaterial (MTM)-based sensors for material characterization, which includes solid…
Abstract
Purpose
This paper aims to concentrate on research that has been conducted in the previous decade on metamaterial (MTM)-based sensors for material characterization, which includes solid dielectrics, micro fluids and biomolecules.
Design/methodology/approach
There has been a vast advancement in sensors based on MTM since the past few decades. MTM elements provide a sensitive response to materials while having a tiny footprint, making them an appealing alternative for realizing diverse sensing devices.
Findings
Related research papers on MTM sensors published in reputable journals were reviewed in this report, with a specific emphasis on the structure, size and nature of the materials characterized. Because electromagnetic wave interaction excites MTM structures, sensing applications around the electromagnetic spectrum are possible.
Originality/value
The paper contains valuable information on MTM sensor technology for material characterization, and this study also highlights the challenges and approaches that will guide future development.
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Marlon Wesley Machado Cunico and Jonas de Carvalho
The purpose of this study is to present a novel additive manufacturing (AM) technology which is based on selective formation of cellulose-acrylate composite. Besides proposing a…
Abstract
Purpose
The purpose of this study is to present a novel additive manufacturing (AM) technology which is based on selective formation of cellulose-acrylate composite. Besides proposing a process that combines the benefits of fibres and photopolymers, this paper reports the development of material, characterisation of a straight line composite formation, adherence between layers and functional feasibility of the proposed concept.
Design/methodology/approach
For the preliminary evaluation of the proposed process, a composite material based on cellulose-photopolymer was developed, while a multi-objective optimisation study indicated the formulation which results in the maximum values of layer adherence, tensile strength of composite and the effect of the water on the mechanical strength of material. For the characterisation of the process, three main subjects were analysed: the characterisation of straight line composite formation, the effect of composite formation process on previous layers and the functional feasibility of technology.
Findings
In the material development, the tensile strength of dry composite was identified between 20 and 30 MPa, while the tensile strength of wet composite was between 5 and 12 MPa. It is important to note that the dry and wet cellulose presented tensile strength, respectively, equal to 15 and 1 MPa, indicating the possibility of residual material removal only with the use of water or other soft solvent. The values of adherence between layers (peeling test) were found to be between 0.12 and 0.15 kgf, and the photopolymer formulation which resulted in the maximum adherence has monomer/oligomer ratio equal to 1.5 and 2 per cent wt of photoinitiator percentual. As result of the optimisation study, the material formulation was compounded by monomer – 10 ml, oligomer – 4.5 ml and photoinitiator – 2 per cent, being found suitable to characterise and evaluate the proposed process. The study of composite formation along a straight line showed values of line width between 1,400 and 3,500 μm in accordance with light power, laser velocity and laser beam diameter. On the other hand, the number of previous layers affected by the composite formation varied from 0 to 4, indicating a potential process limit. In the functional feasibility study, a feasible process window which resulted in the maximum dimensional deviation equal to 0.5 mm was identified. In addition, the mean mechanical tensile strength was found to be around 30 MPa for longitudinal laser trajectory (90°) and 15 MPa for transversal laser trajectory (0°), highlighting the anisotropic behaviour of final parts according to the manufacturing strategy.
Originality/value
This paper proposed a novel AM technology and also described studies related to the characterisation of this concept. This work might also be useful to the development of other AM processes and applications.
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Chien‐Yi Huang, Ming‐Shu Li, Chen‐Liang Ku, Hao‐Chun Hsieh and Kung‐Cheng Li
The purpose of this paper is to discuss the chemical characterization of failures and process materials for microelectronics assembly.
Abstract
Purpose
The purpose of this paper is to discuss the chemical characterization of failures and process materials for microelectronics assembly.
Design/methodology/approach
The analytical techniques used for chemical structures and compositions including Fourier transform infrared spectrometer (FTIR), scanning electron microscopy, and energy‐dispersive X‐ray spectroscopy are conducted.
Findings
The residues on the golden finger are identified to be the flux used in the assembly processes. Besides, the contaminants on the processed and incoming connector pins are verified to be polyamides (–CONH functional groups) from housing material's residue. Three liquid fluxes used in wave soldering are analyzed by their chemical structure. One flux showing the OH groups at 3430 cm−1 indicates higher acid contents. This consists with the acidic values specified by the supplier. Also, the solder mask under study has ever appeared peeled‐off issue. The FTIR spectra results indicated 62.2 percent degree of curing while vendor's spec is above 70 percent.
Originality/value
The establishment of the Infrared spectra database for fluxes and process materials help determine the root cause of the contaminants to reduce re‐occurrence of similar problems and thus enhance the manufacturing capability. The infrared spectrophotometry technique can be used by professional original design manufacturing and/or electronics manufacturing service, providers to investigate board/component defects during product pilot run stage and volume production.
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Connor Shane Smith, Alanna Julius, Christian Arbeeny and John Davenport Stevens
Radio frequency (RF) technology relies on the electromagnetic properties of the materials used, which includes their complex permittivities and loss tangents. To measure these…
Abstract
Purpose
Radio frequency (RF) technology relies on the electromagnetic properties of the materials used, which includes their complex permittivities and loss tangents. To measure these properties, techniques for material characterization such as the transmission/reflection method are used in conjunction with conversion techniques to calculate these values from scattering parameters. Unfortunately, these techniques rely on relatively expensive rectangular waveguide adaptors and components, especially if testing over large frequency ranges. This paper aims to overcome this challenge by developing a more affordable test equipment solution based on additively manufactured waveguide sections.
Design/methodology/approach
To evaluate the effectiveness of using additively manufactured waveguides to perform electromagnetic characterization with the transmission/reflection method, samples of PLA Tough with varying infill percentages and samples made from several Formlabs photopolymer resins are fabricated and analyzed.
Findings
Results show that the method yielded permittivity and loss tangent values for the measured materials that generally agree with those found in the literature, supporting its credibility.
Originality/value
The accessibility of this measurement technique will ideally allow for more electromagnetic material characterization to occur and expand the possible use of additive manufacturing in future RF designs. This work also provides characterization of several Formlabs photopolymer resins, which have not been widely analyzed in the current literature.
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Mica Grujicic, Jennifer Snipes, S Ramaswami and Chian-Fong Yen
The weld region obtained during friction stir welding (FSW) of metallic materials (including aluminum alloys) contains typically well-defined zones, each characterized by fairly…
Abstract
Purpose
The weld region obtained during friction stir welding (FSW) of metallic materials (including aluminum alloys) contains typically well-defined zones, each characterized by fairly unique microstructure and properties. The purpose of this paper is to carry out combined experimental and numerical investigations of the mechanical properties of materials residing in different weld zones of FSW joints of thick AA2139-T8 plates.
Design/methodology/approach
Within the experimental investigation, the following has been conducted: first, optical-microscopy characterization of the transverse sections of the FSW joints, in order to help identify and delineate weld zones; second, micro hardness field generation over the same transverse section in order to reconfirm the location and the extent of various weld zones; third, extraction of miniature tensile specimens from different weld zones and their experimental testing; and finally, extraction of a larger size tensile specimen spanning transversely the FSW weld and its testing. Within the computational investigation, an effort was made to: first, validate the mechanical properties obtained using the miniature tensile specimens; and second, demonstrate the need for the use of the miniature tensile specimens.
Findings
It is argued that the availability of weld-zone material mechanical properties is critical since: first, these properties are often inferior relative to their base-metal counterparts; second, the width of the weld in thick metallic-armor is often comparable to the armor thickness, and therefore may represent a significant portion of the armor exposed-surface area; and finally, modeling of the weld-material structural response under loading requires the availability of high-fidelity/validated material constitutive models, and the development of such models requires knowledge of the weld-material mechanical properties.
Originality/value
The importance of determining the mechanical properties of the material in different parts of the weld zone with sufficient accuracy is demonstrated.
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Clinton B. Morris, John M. Cormack, Mark F. Hamilton, Michael R. Haberman and Carolyn C. Seepersad
Microstereolithography is capable of producing millimeter-scale polymer parts having micron-scale features. Material properties of the cured polymers can vary depending on build…
Abstract
Purpose
Microstereolithography is capable of producing millimeter-scale polymer parts having micron-scale features. Material properties of the cured polymers can vary depending on build parameters such as exposure. Current techniques for determining the material properties of these polymers are limited to static measurements via micro/nanoindentation, leaving the dynamic response undetermined. The purpose of this paper is to demonstrate a method to measure the dynamic response of additively manufactured parts to infer the dynamic modulus of the material in the ultrasonic range.
Design/methodology/approach
Frequency-dependent material parameters, such as the complex Young’s modulus, have been determined for other relaxing materials by measuring the wave speed and attenuation of an ultrasonic pulse traveling through the materials. This work uses laser Doppler velocimetry to measure propagating ultrasonic waves in a solid cylindrical waveguide produced using microstereolithography to determine the frequency-dependent material parameters of the polymer. Because the ultrasonic wavelength is comparable with the part size, a model that accounts for both geometric and viscoelastic dispersive effects is used to determine the material properties using experimental data.
Findings
The dynamic modulus in the ultrasonic range of 0.4-1.3 MHz was determined for a microstereolithography part. Results were corroborated by using the same experimental method for an acrylic part with known properties and by evaluating the natural frequency and storage modulus of the same microstereolithography part with a shaker table experiment.
Originality/value
The paper demonstrates a method for determining the dynamic modulus of additively manufactured parts, including relatively small parts fabricated with microstereolithography.
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Manuel Julio García Ruíz and Leidy Yarime Suárez González
This work presents a review of the application of hyperelastic models to the analysis of fabrics using finite element analysis (FEA).
Abstract
Purpose
This work presents a review of the application of hyperelastic models to the analysis of fabrics using finite element analysis (FEA).
Design/methodology/approach
In general, a combination of uniaxial tension (compression), biaxial tension, and simple shear is required for the characterization of a hyperelastic material. However, the use of these deformation tests to obtain the mechanical properties of a fabric may be complicated and also expensive. A methodology for characterizing the fabric employing a different experimental test is presented. The methodology consists of a comparison of the results of the fabric characterization with only a tensile test and the combination of shear, biaxial, and tension experimental tests by using FEA.
Findings
Numerical results of the fabric behavior contribute to estimate the effects of experimental limitations in the material characterization and to select the best fit material model to modeling fabrics. Finally, a comparison of hyperelastic material models is illustrated through an example of a rigid body in contact with a hyperelastic fabric in 3D.
Originality/value
Hyperelastic models are used to characterize textile materials.
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Roberto Junior Algarín Roncallo, Luis Lisandro Lopez Taborda and Diego Guillen
The purpose of this research is present an experimental and numerical study of the mechanical properties of the acrylonitrile butadiene styrene (ABS) in the additive manufacturing…
Abstract
Purpose
The purpose of this research is present an experimental and numerical study of the mechanical properties of the acrylonitrile butadiene styrene (ABS) in the additive manufacturing (AM) by fused filament fabrication (FFF). The characterization and mechanical models obtained are used to predict the elastic behavior of a prosthetic foot and the failure of a prosthetic knee manufactured with FFF.
Design/methodology/approach
Tension tests were carried out and the elastic modulus, yield stress and tensile strength were evaluated for different material directions. The material elastic constants were determined and the influence of infill density in the mechanical strength was evaluated. Yield surfaces and failure criteria were generated from the tests. Failures over prosthetic elements in tridimensional stresses were analyzed; the cases were evaluated via finite element method.
Findings
The experimental results show that the material is transversely isotropic. The elasticity modulus, yield stress and ultimate tensile strength vary linearly with the infill density. The stresses and the failure criteria were computed and compared with the experimental tests with good agreement.
Practical implications
This research can be applied to predict failures and improve reliability in FFF or fused deposition modeling (FDM) products for applications in high-performance industries such as aerospace, automotive and medical.
Social implications
This research aims to promote its widespread adoption in the industrial and medical sectors by increasing reliability in products manufactured with AM based on the failure criterion.
Originality/value
Most of the models studied apply to plane stress situations and standardized specimens of printed material. However, the models applied in this study can be used for functional parts and three-dimensional stress, with accuracy in the range of that obtained by other researchers. The researchers also proposed a method for the mechanical study of fragile materials fabricated by processes of FFF and FDM.
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