Journal articles: 'Embedded wires'

1

Cho, Won Woo, G. Zouganelis, and Hitoshi Ohsato. "Enhancement of Electric Field inside Metallodielectric Metamaterial." Advanced Materials Research 11-12 (February 2006): 117–20. http://dx.doi.org/10.4028/www.scientific.net/amr.11-12.117.

Full text

Abstract:

A metallodielectric metamaterial have been investigated by using FDTD (Finite Difference Time Domain) method and fabricated with a resin based rapid prototyping machine. It was composed of 7 layers of parallel periodic copper wires embedded in resin. The metallodielectric metamaterial shows a different near field distribution with direction of incident electric field E that causes different electromagnetic (EM) properties. In particular, when incident electric field E is vertical to the wires inside resin, we observe enhacement of electric field in the vicinity of the embedded metal wires according to the incident direction of electirc field E as compared with dielectirc wihout metal wires. The enhanced electric field by the embedded metal wire is responsible for the enhancement of effective dielectric constant.

APA, Harvard, Vancouver, ISO, and other styles

2

Mahmood Baitab, Danish, Dayang Laila Abang Haji Abdul Majid, Ermira Junita Abdullah, and Mohd Faisal Abdul Hamid. "A review of techniques for embedding shape memory alloy (SMA) wires in smart woven composites." International Journal of Engineering & Technology 7, no. 4.13 (October 9, 2018): 129. http://dx.doi.org/10.14419/ijet.v7i4.13.21344.

Full text

Abstract:

Metallic structures, in various industrial fields such as transport and aerospace, are mostly replaced by composite structures having less weight and good strength. There is also a need of intensification of the operational dynamic environment with high durability requirements. So a smart composite structure is required that can manifest its functions according to environmental changes. One method of producing smart composite structures is to embed shape memory alloys in composite structures. Shape memory alloys (SMAs) have significant mechanical and thermodynamic properties and are available in very small diameters less than 0.2mm. These SMAs are embedded into composites for obtaining smart composites having tunable properties, active abilities, damping capacity and self-healing properties. Shape memory alloys are available in different shapes as wires, sheets, foils, strips, etc. For smart composites, mostly SMA embedded are in wire shape. Different techniques are used for embedding SMA wires in composites. SMA wires can be embedded between layers of laminates of composites, or embedded directly as reinforcement in matrix and can be woven into fabrics and used as a reinforcement. This paper reviews the different techniques of embedding SMA wires in composite structures, their pros and cons and their applications.

APA, Harvard, Vancouver, ISO, and other styles

3

Ren, Yongsheng, Qiyi Dai, Ruijun An, and Youfeng Zhu. "Modeling and Dynamical Behavior of Rotating Composite Shafts with SMA Wires." Shock and Vibration 2014 (2014): 1–16. http://dx.doi.org/10.1155/2014/765875.

Full text

Abstract:

A dynamical model is developed for the rotating composite shaft with shape-memory alloy (SMA) wires embedded in. The rotating shaft is represented as a thin-walled composite of circular cross-section with SMA wires embedded parallel to shaft’s longitudinal axis. A thermomechanical constitutive equation of SMA proposed by Brinson is employed and the recovery stress of the constrained SMA wires is derived. The equations of motion are derived based on the variational-asymptotical method (VAM) and Hamilton’s principle. The partial differential equations of motion are reduced to the ordinary differential equations of motion by using the Galerkin method. The model incorporates the transverse shear, rotary inertia, and anisotropy of composite material. Numerical results of natural frequencies and critical speeds are obtained. It is shown that the natural frequencies of the nonrotating shaft and the critical rotating speed increase as SMA wire fraction and initial strain increase and the increase in natural frequencies becomes more significant as SMA wire fraction increases. The initial strain of SMA wires appears to have marginal effect on dynamical behaviors of the shaft. The actuation performance of SMA wires is found to be closely related to the ply-angle.

APA, Harvard, Vancouver, ISO, and other styles

4

Rajasekhar, J., and Dr JKR Sastry. "An approach to hybridisation of embedded system networks." International Journal of Engineering & Technology 7, no. 2.7 (March 18, 2018): 384. http://dx.doi.org/10.14419/ijet.v7i2.7.10748.

Full text

Abstract:

Embedded systems can be networked using either wired or wireless technologies. ES systems when networked using wires can communicate serially over a bus using the technologies such as CAN, I2C, USB, RS485, and Fire wire. These standards differ in many ways which include arbitration, synchronization, address resolution, timing, type of communication etc. Embedded systems can also be network using wireless technologies which exits in many versions.Several applications these days are requiring more than one communication technology. Several sub-systems are developed using a networking method and it requires that the subsystems that are networked using different technologies are to be networked further for realizing entire application. Such a network needs to deal with many of the heterogeneous communication system leading to an issue of hybridisation. In this paper various issues/approaches that need to be addressed for hybridising of the ES networks have been presented.

APA, Harvard, Vancouver, ISO, and other styles

5

Yang, K., and C. L. Gu. "Research and application of novel planar bending embedded shape memory alloy actuator." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 221, no. 2 (February 1, 2007): 249–57. http://dx.doi.org/10.1243/0954406jmes453.

Full text

Abstract:

To overcome low-response speed and low-control precision in the existing traditional shape memory alloy (SMA) actuators, a new type of structure named planar bending embedded SMA actuator was developed. Two SMA wires were embedded in parallel with the axis of the elastic rod. The recovering wire, which was superposed along rod's axis, was set to obtain ‘U’ memory shape and the restoring wire, which was placed off-axially, got straight memory shape. The differential stain gauges were located at suitable position in corresponding to the actuator's bending direction in order to measure the signal of displacement. By making use of continuity, common origin and common limit conditions, and adjusting martensite fraction coefficients appropriately, the analytical model was deduced to adequately account for the presence of major and minor hysteresis loops. The structural parameters of 60 mm long actuator, such as rod's radius, wire's radius, wire's recoverable curvature, and offset distance, were optimized by combining analytical model with experimental results. The experimental results prove the merits in optimal prototype.

APA, Harvard, Vancouver, ISO, and other styles

6

Park, Jeong Eun, Won Seok Choi, and Donggun Lim. "Cell/Module Integration Technology with Wire-Embedded EVA Sheet." Applied Sciences 11, no. 9 (May 2, 2021): 4170. http://dx.doi.org/10.3390/app11094170.

Full text

Abstract:

Silicon wafers are crucial for determining the price of solar cell modules. To reduce the manufacturing cost of photovoltaic devices, the thicknesses of wafers are reduced. However, the conventional module manufacturing method using the tabbing process has a disadvantage in that the cell is damaged because of the high temperature and pressure of the soldering process, which is complicated, thus increasing the process cost. Consequently, when the wafer is thinned, the breakage rate increases during the module process, resulting in a lower yield; further, the module performance decreases owing to cracks and thermal stress. To solve this problem, a module manufacturing method is proposed in which cells and wires are bonded through the lamination process. This method minimizes the thermal damage and mechanical stress applied to solar cells during the tabbing process, thereby manufacturing high-power modules. When adopting this method, the front electrode should be customized because it requires busbarless solar cells different from the existing busbar solar cells. Accordingly, the front electrode was designed using various simulation programs such as Griddler 2.5 and MathCAD, and the effect of the diameter and number of wires in contact with the front finger line of the solar cell on the module characteristics was analyzed. Consequently, the efficiency of the module manufactured with 12 wires and a wire diameter of 0.36 mm exhibited the highest efficiency at 20.28%. This is because even if the optical loss increases with the diameter of the wire, the series resistance considerably decreases rather than the loss of the short-circuit current, thereby improving the fill factor. The characteristics of the wire-embedded ethylene vinyl acetate (EVA) sheet module were confirmed to be better than those of the five busbar tabbing modules manufactured by the tabbing process; further, a high-power module that sufficiently compensated for the disadvantages of the tabbing module was manufactured.

APA, Harvard, Vancouver, ISO, and other styles

7

Hack, Harvey, and James Windgassen. "Permeation of Artificial Seawater into Polyurethane and Its Effect on the Performance of Potted Electrical Equipment." Corrosion 78, no. 4 (February 15, 2022): 369–73. http://dx.doi.org/10.5006/3848.

Full text

Abstract:

Measurements were conducted to quantify the permeation of artificial seawater into various polyurethanes and polyethylene as a function of time and temperature. Both weight gain from water absorption and an electrical current between pairs of wires embedded into the polyurethanes were measured over a period of several months at 50°C. Water was absorbed into all materials, including polyethylene, but there was no increase in the current between wire pairs embedded in the polyurethanes, indicating that the water that was able to permeate was pure water of high resistivity whereas the charged ions in the seawater were not able to permeate to the wires.

APA, Harvard, Vancouver, ISO, and other styles

8

Yang, Qing Ping, Li Sun, and Yan Zhong Feng. "Experiment of Beam Crack Repair Using Shape Memory Alloy." Applied Mechanics and Materials 71-78 (July 2011): 1707–10. http://dx.doi.org/10.4028/www.scientific.net/amm.71-78.1707.

Full text

Abstract:

In this paper, the repair capacity of SMA wire by using internal and external installation was studied. The SMA wires were embedded in epoxy resin and silicon cement mortar beams made of polymer clay, and then three-point bending test was conducted on the composite beam. The ability of beams which embedded SMA wires was also studied. On the other hand, the SMA wires were installed in the external of the epoxy polymer clay cement mortar, then three point bending test was also used and its self-repair ability was also studied. The results show that the crack can be repaired very well under these two methods. If there are cracks in existing buildings, we can use an external installation method to repair them. In order to ensure the new buildings crack free, both methods are feasible.

APA, Harvard, Vancouver, ISO, and other styles

9

CITRIN, D. S. "EXCITONS IN SEMICONDUCTOR QUANTUM WIRES: RADIATIVE LIFETIMES AND POLARITONS." Modern Physics Letters B 07, no. 23 (October 10, 1993): 1467–89. http://dx.doi.org/10.1142/s021798499300151x.

Full text

Abstract:

Radiative effects felt by excitons in semiconductor quantum wires are reviewed. The interaction of an exciton with the electromagnetic field is responsible for the formation of exciton polaritons, for vacuum-field Rabi oscillations, and for spontaneous emission. It is shown that exciton radiative lifetimes in defect-free quantum wires are expected to be longer than in quantum wells of comparable size. Schemes for controlling spontaneous emission and polariton dispersion, such as the use of quantum-wire arrays and cavity-embedded structures, are discussed.

APA, Harvard, Vancouver, ISO, and other styles

10

Alebrahim, Reza, M. Iqram, M. Farizal, S. S. K. Singh, S. M. Haris, A. K. Elwaleed, and N. Nikabdullah. "Control of Crack Propagation in Composite Fiberglass-Polyester Laminates Using Nitinol Wire." Applied Mechanics and Materials 663 (October 2014): 108–12. http://dx.doi.org/10.4028/www.scientific.net/amm.663.108.

Full text

Abstract:

The experimental analysis presents the control of cracked composite fiberglass-polyester by using reinforced Shape Memory Alloy (SMA). SMA wires were used to control and close the crack gap in the composite. The experimental analysis was conducted for one and two SMA wires, whereby these SMA wires were heat treated and trained before being embedded into the fiberglass matrix strip. The composite reinforced strips were pre-notched as a criterion for crack initiation and propagation under gradual tensile loading. It was observed, a complete separation into two pieces of the strip was hindered by the existence of the SMA wires. The control of cracked composite is based on the changing of resistance of the SMA wire during the deformation phase. The variation of the resistance in the stretched SMA wire acts as a feedback to the on-off controller. It was observed during the experimental analysis that when the electric current of 2 Amps is switched on, the wires temperature will be increased until 60°C to produce a contraction effect, hence this effect will close the cracks that occurred under loading condition.

APA, Harvard, Vancouver, ISO, and other styles

11

Choi, Eunsoo, Baik-Soon Cho, Joonam Park, and Kyoungsoo Park. "Inducing recovery stress of NiTiNb SMA wires using heat of hydration for confining concrete." Journal of Intelligent Material Systems and Structures 22, no. 17 (September 6, 2011): 1949–57. http://dx.doi.org/10.1177/1045389x11420587.

Full text

Abstract:

This study suggests the utilization of heat of hydration of concrete to activate the shape memory effect (SME) of shape memory alloy (SMA) wires embedded in concrete and produce recovery and residual stress on the wires. This method is more convenient than the previous electronic resistance heating. For the purpose, this study prepares NiTiNb SMA wires that show appropriate temperature window for the use of heat of hydration. Axial compressive tests of concrete cylinders confined by the NiTiNb SMA wire jackets are used to prove that the utilization of heat of hydration is valid to generate recovery and residual stress in the SMA wires. The confined cylinders show increased peak strengths and much larger failure strains than those of the plain concrete. The general behavior of the SMA wire-confined specimens in this study is similar to that of specimens heated by electronic heating jacket. Also, this study explains two examples for the utilization of heat of hydration for the SME in reinforced concrete beams and columns.

APA, Harvard, Vancouver, ISO, and other styles

12

Ren, Jian, and Q. Liu. "Thermal Vibration Characteristics Analysis of a Composite Thin-Cylindrical Shell Embedded with Shape Memory Alloy Wires." Key Engineering Materials 334-335 (March 2007): 933–36. http://dx.doi.org/10.4028/www.scientific.net/kem.334-335.933.

Full text

Abstract:

Thermal vibration characteristics of the composite thin-cylindrical shell embedded with shape memory alloy (SMA) fibers are investigated. The shape memory alloy material behavior is programmed in the form of an ABAQUS user subroutine code (UMAT), and this program is successfully verified by using the response of pseudoelasticity and the shape memory effect (SME) at various temperatures and stress levels. Based on the ABAQUS UMAT code, the natural frequency of the composite thin-cylindrical shell embedded with SMA wires under thermal load and mechanical load is calculated respectively. Then the effects of the SMA wire temperature and the content on the thermal vibration characteristics of the structure are discussed. Numerical simulation results show that the temperature and the volume content of the SMA wires increase the stiffness and buckling critical load of the structure.

APA, Harvard, Vancouver, ISO, and other styles

13

Murugesan, Kannan, Kalaichelvan K., M. P. Jenarthanan, and Sornakumar T. "Enhancement of vibration characteristics in filament wound FRP composite shafts using nitinol wires." Pigment & Resin Technology 47, no. 5 (September 3, 2018): 377–85. http://dx.doi.org/10.1108/prt-11-2017-0087.

Full text

Abstract:

Purpose The purpose of this paper is to investigate the use of embedded Shape Memory Alloy (SMA) nitinol wire for the enhancement of vibration and damping characteristics of filament-wound fiber-reinforced plastic composite hollow shafts. Design/methodology/approach The plain Glass Fiber-Reinforced Plastic (GFRP) and plain Carbon Fiber-Reinforced Plastic (CFRP) hollow shafts were manufactured by filament winding technique. Experimental modal analysis was conducted for plain hollow shafts of C1045 steel, GFRP and CFRP by subjecting them to flexural vibrations as per ASTM standard C747, with both ends clamped (C-C) end condition to investigate their vibration and damping behavior in terms of first natural frequency, damping time and damping ratio. Nitinol wires pre-stressed at various pre-strains (2, 4 and 6 per cent) were embedded with CFRP hollow shafts following same manufacturing technique, and similar experimental modal analysis was carried out by activating nitinol wires. The first natural frequencies of all the shaft materials were also predicted theoretically and compared with experimental measurements. Findings Among the three materials C1045 steel, plain GFRP and plain CFRP, the vibration and damping behavior were found to be the best for plain CFRP. Hence, CFRP shafts were considered for further improvement by embedding nitinol wires at pre-stressed condition. For CFRP shafts embedded with nitinol wires, the damping time decreased; and damping ratio and first natural frequency increased with increase in percentage of pre-strain. In comparison with plain CFRP, 7 per cent increase in first natural frequency and 100 per cent increase in damping ratio were observed for nitinol embedded CFRP shafts with 6 per cent pre-strain. Theoretical predictions of the first natural frequencies agree well with the experimental results for all the shaft materials. Originality/value The effect of nitinol on vibration and damping characteristics of filament wound hollow CFRP composite shafts with different pre-strains has not been studied extensively by the previous researchers. This paper addresses the effect of embedded nitinol wires pre-stressed at three varied pre-strains, that is, 2, 4 and 6 per cent on the vibration and damping characteristics of composite hollow CFRP shafts manufactured by filament winding technique.

APA, Harvard, Vancouver, ISO, and other styles

14

Kontaxis, Lykourgos C., Athanasios Kotrotsos, Spyros Verbis, and George C. Papanicolaou. "Embedded Resistance Wire Technique for Epoxy Curing and Self-Healing of PET Thermoplastics." Solids 2, no. 3 (September 3, 2021): 314–30. http://dx.doi.org/10.3390/solids2030020.

Full text

Abstract:

The aim of the present study is to apply an embedded resistance wire technique for curing of thermosetting resins as well as for the self-healing of thermoplastic polymers. The work consists of two parts. In the first part, Kanthal resistance wires embedded in a resin plate acted as heating elements when direct electrical current was flowing through them (Joule heating). During heating, the temperature was continuously monitored using a thermal camera, and accurate temperature times for fixed position diagrams as well as temperature positions for fixed time diagrams were calculated. The effects of curing with this method were evaluated by studying the three-point bending mechanical behavior of the cured resin, comparing it with the corresponding behavior of the same resin when cured using a conventional oven curing method at the same temperature. In the second part of the present work, the possibility of using the same technique for healing existing notches and flaws in a PET thermoplastic is explored. We examined whether providing energy through the resistance wires created the right amount of heat to heal the thermoplastic, or, more specifically, whether it closed the notches and eliminated the abrasions that were artificially created on the specimens. The technique using embedded resistance wires worked equally well, with interesting and promising preliminary results regarding the curing of thermoset resins and the healing of thermoplastics.

APA, Harvard, Vancouver, ISO, and other styles

15

Kheirikhah, Mohammad M., Mahdi Khadem, and Peyman Farahpour. "Bending analysis of soft core sandwich plates with embedded shape memory alloy wires using three-dimensional finite element method." Proceedings of the Institution of Mechanical Engineers, Part L: Journal of Materials: Design and Applications 226, no. 3 (April 30, 2012): 186–202. http://dx.doi.org/10.1177/1464420712446277.

Full text

Abstract:

In this article, bending behavior of the sandwich plates with embedded shape memory alloy wires in their face sheets is studied. Three-dimensional finite element method is used for constructing and analyzing the sandwich plates with flexible core and two stiff face sheets. Some important points such as continuity conditions of the displacements, satisfaction of inter-laminar transverse shear stresses, conditions of zero transverse shear stresses on the upper and lower surfaces and in-plane and transverse flexibility of the soft core are considered for the accurate modeling of the sandwich plate. Solutions for bending analysis of shape memory alloy wire-reinforced sandwich plates under various transverse loads are presented and the effects of plate dimensions, shape memory alloy wires diameter, boundary conditions and shape memory alloy wires embedding positions are studied. Comparison of the present results in special case with those of the three-dimensional theory of elasticity and some plate theories confirms the accuracy of the proposed model. According to the obtained numerical results, the local behavior of the sandwich plate in bending against various loading conditions was significantly improved by employing the shape memory alloy wires in the face sheets.

APA, Harvard, Vancouver, ISO, and other styles

16

Atiyah, Qasim Abbas, Ammar Saleem Hameed, and Baqer Jabbar Assi. "Vibration Analysis of Uniform and Tapered Composite Beams with Embedded Shape Memory Alloy." Journal of University of Babylon for Engineering Sciences 27, no. 1 (January 28, 2019): 82–93. http://dx.doi.org/10.29196/jubes.v27i1.1972.

Full text

Abstract:

In this study, laminated composite materials were hybridized with E-glass fiber and Nitinol (Nickel-Titanium) wires. Hand lay-up technique was used to prepare the samples, epoxy resin type (Sikadur 52 N) was used as matrix reinforced by one fiber from E-glass fiber woven roving with embedded nitinol wires with a diameter 0.5 mm for samples and number of wires such as 0, 1, 3, 5 and 9 to find the effect of the number of wires on the natural frequency. The samples were fixed as a cantilever beam. The effects of increasing the number of nitinol wires, the diameter of nitinol wires, the length of the cantilever beam and the thickness of beam on the natural frequencies of the beam were studied. Also, the effects of the tapered in width side and thickness side on the natural frequencies of cantilever beam were studied. The results showed that the increasing in the number of nitinol wires and the diameter of nitinol wires lead to decrease the natural frequency in martensite phase and increase the natural frequency in austenite phase. Also, the increasing in thickness of beam and width ratio of the beam lead to increase the natural frequency. As well as, the increasing in the thickness ratio leads to increase the first natural frequency and decrease the second and third ones. In addition, the increasing in the length of the beam decreases the natural frequency.

APA, Harvard, Vancouver, ISO, and other styles

17

Wu, Ye, and Yun Wan. "The low-velocity impact and compression after impact (CAI) behavior of foam core sandwich panels with shape memory alloy hybrid face-sheets." Science and Engineering of Composite Materials 26, no. 1 (January 28, 2019): 517–30. http://dx.doi.org/10.1515/secm-2019-0034.

Full text

Abstract:

AbstractDue to the properties of shape memory effect and super-elasticity, shape memory alloy (SMA) is added into glass fiber reinforced polymer (GFRP) face-sheets of foam core sandwich panels to improve the impact resistence performance by many researchers. This paper tries to discuss the failure mechanism of sandwich panels with GF/ epoxy face-sheets embedded with SMA wires and conventional 304 SS wire nets under low-velocity impact and compression after impact (CAI) tests. The histories of contact force, absorbed energy and deflection during the impact process are obtained by experiment. Besides, the failure modes of sandwich panels with different ply modes are compared by visual inspection and scanning electron microscopy (SEM). CAI tests are conducted with the help of digital image correlation (DIC) technology. Based on the results, the sandwich panels embedded with SMA wires can absorb more impact energy, and show relatively excellent CAI performance. This is because the SMA wires can absorb and transmit the energy to the outer region of GFRP face-sheet due to the super-elasticity-behavior. The failure process and mechanism of the CAI test is also discussed.

APA, Harvard, Vancouver, ISO, and other styles

18

Eslami-Farsani, Reza, and Masoud Khazaie. "Effect of shape memory alloy wires on high-velocity impact response of basalt fiber metal laminates." Journal of Reinforced Plastics and Composites 37, no. 5 (November 29, 2017): 300–309. http://dx.doi.org/10.1177/0731684417744054.

Full text

Abstract:

Fiber metal laminates are commonly used materials in industrial applications due to low density and excellent mechanical properties such as impact resistance. In this study, the effect of shape memory alloy wires on the impact properties of fiber metal laminates is evaluated and discussed. The volume fraction of wires and the pre-strain of wires were selected as the variables of the experiments. The samples were fabricated using hand lay-up method and their behavior was evaluated under high-velocity impact test. Based on the results, a significant change in the amount of absorbed energy was obtained using embedded wires. However, with increasing the volume fraction of wires, the absorbed energy decreases due to the discontinuity in mechanical properties of the specimens. On the other hand, applying pre-strain leads to residual stresses in samples. The observed residual stress in specimens with four embedded wires and 2% pre-strain level shows the most absorbed energy.

APA, Harvard, Vancouver, ISO, and other styles

19

Sidhu, Varinder Pal Singh, Mark R. Towler, and Marcello Papini. "Measurement of Adhesion of Sternal Wires to a Novel Bioactive Glass-Based Adhesive." Journal of Functional Biomaterials 10, no. 3 (August 9, 2019): 37. http://dx.doi.org/10.3390/jfb10030037.

Full text

Abstract:

Stainless steel wires are the standard method for sternal closure because of their strength and rigidity, the simplicity of the process, and the short healing time that results from their application. Despite this, problems still exist with sternal stability due to micromotion between the two halves of the dissected and wired sternum. Recently, a novel glass-based adhesive was developed which, in cadaveric trials and in conjunction with wiring, was shown to restrict this micromotion. However, in order to avoid complications during resternotomy, the adhesive should adhere only to the bone and not the sternal wire. In this study, sternal wires were embedded in 8 mm discs manufactured from the novel glass-based adhesive and the constructs were then incubated at 37 °C for one, seven, and 30 days. The discs were manufactured in two different thicknesses: 2 and 3 mm. Wire pull-out tests were then performed on the constructs at three different strain rates (1, 0.1, and 0.01 mm/min). No statistically significant difference in pull-out force was found regardless of incubation time, loading rate, or construct thickness. The pull-out forces recorded were consistent with static friction between the wire and adhesive, rather than the adhesion between them. Scanning electron micrographs provided further proof of this. These results indicate that the novel adhesive may be suitable for sternal fixation without complicating a potential resternotomy.

APA, Harvard, Vancouver, ISO, and other styles

20

CHELLADURAI, SAMSON JEROLD SAMUEL, and RAMESH ARTHANARI. "INVESTIGATION ON MECHANICAL AND WEAR PROPERTIES OF ZINC-COATED STEEL WIRES REINFORCED LM6 ALUMINIUM ALLOY COMPOSITES BY SQUEEZE CASTING." Surface Review and Letters 26, no. 01 (January 2019): 1850125. http://dx.doi.org/10.1142/s0218625x18501251.

Full text

Abstract:

Zinc-coated steel wires (1–5 numbers) reinforced in LM6 matrix composites have been prepared by squeeze casting process. Microstructure, hardness, tensile strength, ductility and dry sliding wear behavior of composites have been investigated by varying sliding distance and load. Fracture surface of tensile specimens and worn out surface of wear samples have been examined using field emission scanning electron microscope (FESEM). The results reveal that hardness of composites increased with increasing distance from matrix to steel wires. Maximum hardness values of 751 VHN and 611 VHN are observed in steel wire and at the interface of steel wire — aluminium, respectively. Tensile strength of composites increased upto 24% by reinforcing three steel wires in matrix. During the wear test, weight loss, wear rate and coefficient of friction decreased with increasing number of wires embedded in matrix and increased with increasing sliding distance and load. LM6 aluminium alloy reinforced with five numbers of steel wires decreased the weight loss upto 17% as compared to matrix under 40[Formula: see text]N load and a sliding distance of 2000[Formula: see text]m. Fracture surface of tensile specimen shows dimple formation in matrix and broken wires are observed in composites. Worn surface of composites shows fine grooves, whereas delamination is observed in matrix. In general, reinforcement of zinc-coated steel wires in LM6 aluminium alloy exhibited better mechanical properties and wear resistance compared to matrix.

APA, Harvard, Vancouver, ISO, and other styles

21

Chiu, C. H., and Hangyao Wang. "First-order perturbation solutions of embedded strained wires." Journal of Applied Physics 100, no. 12 (December 15, 2006): 123506. http://dx.doi.org/10.1063/1.2400392.

Full text

APA, Harvard, Vancouver, ISO, and other styles

22

Christopoulos, A. C., I. Koulalis, G. J. Tsamasphyros, and G. Kanderakis. "Investigation of Strain Sensing Capabilities of Amorphous Magnetostrictive Wires Embedded in Epoxy Resin." Key Engineering Materials 495 (November 2011): 276–79. http://dx.doi.org/10.4028/www.scientific.net/kem.495.276.

Full text

Abstract:

The development of fibers and adhesive systems with high durability has recently led to the creation of a new repair method of metallic structures, by the use of reinforcing patches made of composite materials. This technique is generally reported as "Composite patch repair" and provides very important advantages compared to the conventional methods of repairs. On the other hand, the technology of induction heating constitutes an innovative approach to achieve the supply of energy for the curing of resins or for the manufacturing of composite materials. In the case of resins, a ferromagnetic material must be imported into the resin, to produce the required heat. This may be achieved by importing a metallic grid in the resin. Moreover, this metallic grid, which remains inside the resin after the curing, may serve as sensor by analyzing its electrostatic properties, thus providing useful information about the structural integrity of the area (e.g. potential increase of the crack below a bonded composite repair). In this paper we present results concerning the strain sensing capabilities of amorphous magnetostrictive wires embedded in epoxy resin. The inverse magnetostrictive effect leads to a change of permeability of wires so that applied stress can change the impedance of the amorphous wires due to the skin effect with alternating current excitation. Two different types of sensing were used, contact sensing (attachment of the wire “gauge” to a sensing devise) and induction sensing (eddy current sensing probe).

APA, Harvard, Vancouver, ISO, and other styles

23

Dos Reis, Rômulo Pierre Batista, Cícero da Rocha Souto, Carlos José de Araújo, Antonio Almeida Silva, and Edson Paulo da Silva. "Vibration Attenuation in an Epoxy Smart Composite Beam with Embedded NiTi Shape Memory Wires." Materials Science Forum 643 (March 2010): 7–13. http://dx.doi.org/10.4028/www.scientific.net/msf.643.7.

Full text

Abstract:

Shape memory alloys (SMA) are thermo-responsive materials where deformation can be induced and recovered through temperature changes. Therefore, SMA are considered smart materials. In this work, an epoxy beam reinforced by NiTi SMA wires was developed. This active composite contains five pre-trained NiTi SMA wire actuators, evenly distributed along the neutral plane of the epoxy beam, which can be activated by resistive heating. The results of different ways for electrical activation of the smart composite in a simply clamped mode are discussed. It was possible to demonstrate the viability of this concept for attenuation of mechanical vibrations by controlled electrical heating of the NiTi wire actuators.

APA, Harvard, Vancouver, ISO, and other styles

24

Vilar, Zoroastro Tôrres, Carlos José de Araújo, and Rômulo Pierre Batista Dos Reis. "Thermal Activation of CFRP with Embedded NiTi Shape Memory Wires." Materials Science Forum 643 (March 2010): 19–28. http://dx.doi.org/10.4028/www.scientific.net/msf.643.19.

Full text

Abstract:

The possibility of uniting two or more different materials to obtain structures capable to feel and adapt to environmental alterations and operational conditions, has been leading to the development of active composites with functional properties that makes possible the control of shape, vibration, rigidity and/or structural integrity monitoring. These characteristics are very well accepted in modern technological applications. In this context, active composites were manufactured using pre-impregnated (Pre-Pregs) of carbon fiber reinforced polymer (CFRP) and NiTi shape memory alloy (SMA) thin wires in different conditions. The functional capacity of the obtained CFRP-NiTi smart composites was verified through detection of buckling and thermal contraction/expansion effects by electrical heating of the NiTi wires inside the CFRP matrix. Although the NiTi wires represent a minimum volumetric fraction in the CFRP-NiTi produced systems, its influence was evidenced.

APA, Harvard, Vancouver, ISO, and other styles

25

Lee, Seung Jo, and Jung Min Park. "An Experimental Study on the Structural Behaviors of HIRC Beams Using Nickel-Titanium SMA Wires." Key Engineering Materials 730 (February 2017): 423–28. http://dx.doi.org/10.4028/www.scientific.net/kem.730.423.

Full text

Abstract:

This paper deals with structural behavior of highly intelligent reinforced concrete (hereinafter, HIRC) beams actuated by embedded shape memory alloy wires through an extensive experimental program. The experiments were conducted under the monotonic loading condition. Based on the structural experiments involving HIRC, load-temperature deflection curve, ductility-effective depth, recovery, crack patterns, and failure mode comparison were made for investigative purposes. The results of the experiments confirmed that the ductility, recovery rates, and other properties of the HIRC specimens reinforced with SMA, wire mesh, fiber, and admixtures were superior to those of the unreinforced RCBs. The experimental results indicate that a good recovery rate in the HIRC beams could be obtained when the SMA wires were heated. Accordingly, the SMA wires could be potentially used for structural self-rehabilitation capability and deformation monitoring in architecture and civil structures.

APA, Harvard, Vancouver, ISO, and other styles

26

Pazhanivel, Kaliyaperumal, G. B. Bhaskar, N. Venkatesan, P. Anandan, and Sabapathy Arunachalam. "Influence of SMA Short Fibers on Mechanical Properties of Copper/GFRP Composites." Applied Mechanics and Materials 591 (July 2014): 64–67. http://dx.doi.org/10.4028/www.scientific.net/amm.591.64.

Full text

Abstract:

Plain GFRP, copper wire embedded GFRP and SMA short fibres included copper wires embedded GFRP laminates have been prepared by hand lay-up method. The mechanical properties like flexural and tensile strength were investigated. To study the impact properties of the laminates an experimental set up was designed and the impact strength of the laminates was studied by drop weight method. Three point bend method was adopted for flexural studies and the tensile strength was found by Instron Machine. It is found that the inclusion of SMA short fibres significantly improved the mechanical properties of the composites.

APA, Harvard, Vancouver, ISO, and other styles

27

Nahvi, H., H. Rezaei, and M. Kadkhodaei. "1C22 Non-linear Vibration Analysis of a Beam with Embedded Shape Memory Alloy Wires." Proceedings of the Symposium on the Motion and Vibration Control 2010 (2010): _1C22–1_—_1C22–16_. http://dx.doi.org/10.1299/jsmemovic.2010._1c22-1_.

Full text

APA, Harvard, Vancouver, ISO, and other styles

28

Zhong, Weiyan, Feng Gao, Yongsheng Ren, Xiaoxiao Wu, and Hongcan Ma. "Dynamic Analysis of a Tapered Composite Thin-Walled Rotating Shaft Embedded with SMA Wires Using the Generalized Differential Quadrature Method." Shock and Vibration 2020 (September 10, 2020): 1–16. http://dx.doi.org/10.1155/2020/3453298.

Full text

Abstract:

A dynamical model is developed for the tapered composite thin-walled rotating shaft with shape memory alloy (SMA) wires embedded in. The SMA wires are embedded at an interlayer of the shaft and arranged along the conical surface of the tapered composite shaft. Recovery stresses generated during the phase transformation are calculated based on one-dimensional Brinson’s model. The governing equations are obtained based on a refined variational asymptotic method (VAM) and Hamilton’s principle. The partial differential equations of motion are reduced to the ordinary differential governing equations by using the generalized differential quadrature method (GDQM). Numerical results of natural frequencies and critical speeds are obtained. The effects of the fraction of SMA wires, the initial strain of SMA wires, temperature, ply angle, taper ratio, boundary conditions, and rotating speed on the frequency characteristics are investigated.

APA, Harvard, Vancouver, ISO, and other styles

29

Khalili, SMR, and A. Saeedi. "Dynamic response of laminated composite beam reinforced with shape memory alloy wires subjected to low velocity impact of multiple masses." Journal of Composite Materials 52, no. 8 (July 21, 2017): 1089–101. http://dx.doi.org/10.1177/0021998317722042.

Full text

Abstract:

The response of laminated hybrid composite beam with embedded shape memory alloy wires subjected to impact of multiple masses is analytically investigated. Two degree of freedom spring-mass system and Fourier series are used in order to study the low velocity impact phenomenon on the resulting hybrid composite beam. A linearized contact law is chosen to calculate the contact force history. The effect of pseudo elasticity of wires as well as the recovery stresses generated in shape memory alloy wires due to shape memory effect is investigated. The beam is subjected to impactors with various masses, radii, and initial velocities. Impacts are occurred on the top and/or bottom surface of the beam. The effects of volume fraction of shape memory alloy wires, location of embedded wires, location of impacts and pre-strain in shape memory alloy wires on the contact force history and the deflection curve of the beam are investigated. The obtained results illustrated that embedding shape memory alloy wires in the laminated composite beam caused the deflection of the beam to occur more local at the points of impact, in comparison with the beams without shape memory alloy wires. Moreover, embedding 0.2 volume fraction of the shape memory alloy wires reduced the maximum deflection of the beam subjected to impact of 2 impactor masses by 57% and 3 impactor masses (on both sides) by 12%. Pre-straining the wires caused more reduction in deflection of the beam under impact loading.

APA, Harvard, Vancouver, ISO, and other styles

30

Qiu, Zi Xue, Jing Ya Wu, Jiang Yuan, Yu Tian Chen, and Yong Jie Yang. "Design of RFID Sensor-Tag for Wireless Monitoring of SMA-Reinforced Composite Structure." Applied Mechanics and Materials 43 (December 2010): 196–200. http://dx.doi.org/10.4028/www.scientific.net/amm.43.196.

Full text

Abstract:

When Shape memory alloy (SMA) wires are embedded in the composite structure with a specific volume fraction, the properties of the resulting hybrid composite structure, which is called SMA-reinforced composite structure, will be reinforced. Some of SMA wires embedded in the composite can be viewed as two electrodes of the capacitor. The deformation of the composite structure will cause change of the capacitor, therefore the segmental SMA wires embedded in the composite may be considered as the self-sensitive element of structure strain monitoring. The measurement circuit monitoring the change of micro capacitor in structure is designed, and it is integrated with radio frequency identification (RFID) technology to compose RFID sensor-tag, and the variation of capacitor is send to the RFID reader wirelessly to form a wireless health monitoring system. Experimental results show that this RFID sensor-tag and its system can be feasibly used in wireless structural health monitoring of SMA-reinforced composite structure.

APA, Harvard, Vancouver, ISO, and other styles

31

Bloomer, C., M. E. Newton, G. Rehm, and P. S. Salter. "A single-crystal diamond X-ray pixel detector with embedded graphitic electrodes." Journal of Synchrotron Radiation 27, no. 3 (March 31, 2020): 599–607. http://dx.doi.org/10.1107/s160057752000140x.

Full text

Abstract:

The first experimental results from a new transmissive diagnostic instrument for synchrotron X-ray beamlines are presented. The instrument utilizes a single-crystal chemical-vapour-deposition diamond plate as the detector material, with graphitic wires embedded within the bulk diamond acting as electrodes. The resulting instrument is an all-carbon transmissive X-ray imaging detector. Within the instrument's transmissive aperture there is no surface metallization that could absorb X-rays, and no surface structures that could be damaged by exposure to synchrotron X-ray beams. The graphitic electrodes are fabricated in situ within the bulk diamond using a laser-writing technique. Two separate arrays of parallel graphitic wires are fabricated, running parallel to the diamond surface and perpendicular to each other, at two different depths within the diamond. One array of wires has a modulated bias voltage applied; the perpendicular array is a series of readout electrodes. X-rays passing through the detector generate charge carriers within the bulk diamond through photoionization, and these charge carriers travel to the nearest readout electrode under the influence of the modulated electrical bias. Each of the crossing points between perpendicular wires acts as an individual pixel. The simultaneous read-out of all pixels is achieved using a lock-in technique. The parallel wires within each array are separated by 50 µm, determining the pixel pitch. Readout is obtained at 100 Hz, and the resolution of the X-ray beam position measurement is 600 nm for a 180 µm size beam.

APA, Harvard, Vancouver, ISO, and other styles

32

Li, Hao, Jingbiao Liu, Zhenqing Wang, Zhengwei Yu, Yanfei Liu, and Min Sun. "The Low Velocity Impact Response of Shape Memory Alloy Hybrid Polymer Composites." Polymers 10, no. 9 (September 14, 2018): 1026. http://dx.doi.org/10.3390/polym10091026.

Full text

Abstract:

Polymer composites are sensitive to impact loading due to their low impact resistance. Shape memory alloy (SMA) wires have been used to improve the impact resistance of the polymer composite materials because of their unique superelasticity performance. In this study, a new SMA hybrid basalt fiber-reinforced polymer composite embedded with two perpendicular layers of superelastic SMA wires is designed and the low-velocity impact behavior is experimental investigated. For contrast, the conventional polymer composite without SMA wires is also tested as the reference laminate. The tests are carried out at three different impact energy levels (30, 60 and 90 J). Moreover, to find out indications for manufacturing of SMA hybrid composites with high impact resistance, four different SMA wires embedded modes are investigated. Visual inspection and scanning electron microscope methods are adopted to identify the damage modes of the impacted samples. Results show that the impact resistance of the hybrid laminates is improved due to the hybridization of SMA wires. The most effective impact resistance of the SMA hybrid composites can be obtained by incorporating the SMA wires with one layer between the front two plies and another layer between the bottom two plies into the composite structure.

APA, Harvard, Vancouver, ISO, and other styles

33

Bartoli, Ivan, Salvatore Salamone, Robert Phillips, Francesco Lanza di Scalea, Stefano Coccia, and Charles S. Sikorsky. "Monitoring Prestress Level in Seven Wire Prestressing Tendons by Inter Wire Ultrasonic Wave Propagation." Advances in Science and Technology 56 (September 2008): 200–205. http://dx.doi.org/10.4028/www.scientific.net/ast.56.200.

Full text

Abstract:

Researchers at UCSD are investigating, in collaboration with Caltrans, the combination of ultrasonic guided waves and embedded sensors as an approach to provide both prestress level monitoring and defect detection capabilities in concrete-embedded PS tendons. This paper will focus on the prestress level monitoring by first discussing the behavior of ultrasonic guided waves propagating in seven-wire, 15.2-mm diameter twisted strands typically used in post-tensioned concrete structures. A semianalytical finite element analysis is used to predict forced wave solutions as a function of the applied prestress level. A feature shown sensitive to load levels is the inter-wire energy leakage. In order to monitor such feature, piezoelectric sensors were experimentally employed to probe the individual, 5-mm wires comprising the strand. Results of load monitoring in embedded strands during laboratory tests will be presented and a statistical approach will be used to enhance the evaluation of prestress loss in the strands.

APA, Harvard, Vancouver, ISO, and other styles

34

Kang, Ki Weon, H. J. Kim, J. H. Kim, Heung Seob Kim, Yong Su Kim, and Young Min Do. "Impact Damage Resistance of Glass/Epoxy Laminates with Embedded Shape Memory Alloy." Key Engineering Materials 345-346 (August 2007): 1529–32. http://dx.doi.org/10.4028/www.scientific.net/kem.345-346.1529.

Full text

Abstract:

This paper deals with the damage resistance of glass/epoxy laminates with embedded shape memory alloy (SMA) subjected to low-velocity impact at various temperatures. For this goal, the impact tests were performed by using an instrumented impact-testing machine at three temperatures: +20°C, -10°C and -40°C. And the resultant damages were inspected through the scanning acoustic microscope (SAM). Also, based on the impact force history and the damage configuration, the impact resistance parameters were employed to evaluate damage resistance of laminates with embedded SMA wires. As results, it was found that the damage resistance of glass/epoxy laminates with embedded SMA wires is dependent on the service temperature.

APA, Harvard, Vancouver, ISO, and other styles

35

Nucera, Claudio, and Francesco Lanza di Scalea. "Monitoring load levels in multi-wire strands by nonlinear ultrasonic waves." Structural Health Monitoring 10, no. 6 (January 11, 2011): 617–29. http://dx.doi.org/10.1177/1475921710395812.

Full text

Abstract:

Monitoring load levels in multi-wire steel strands is relevant to ensuring the proper structural performance of post-tensioned concrete structures, suspension bridges, and cable-stayed bridges. This article investigates the use of ultrasonic nonlinearity as a means to determine the level of load applied to the strands. Since an axial load on a multi-wire strand generates proportional contact stresses between adjacent wires, ultrasonic nonlinearity from the inter-wire contact must be related to the level of axial load. This article shows that the higher harmonic generation of ultrasonic guided waves propagating in individual wires of the strand indeed changes monotonically with the applied load, with smaller higher harmonic amplitudes with increasing load levels. This trend is consistent with known studies on higher harmonic generation from ultrasonic plane waves incident on a contact interface under a changing contact pressure. The article presents experimental studies on free strands and embedded strands, and numerical studies (nonlinear Finite Element Analysis) on free strands.

APA, Harvard, Vancouver, ISO, and other styles

36

Umezaki, Eisaku, and Tadashi Ichikawa. "Measurement of Deformation of Epoxy Resin Plates with an Embedded SMA Wire Using Digital Image Correlation." International Journal of Modern Physics B 17, no. 08n09 (April 10, 2003): 1750–55. http://dx.doi.org/10.1142/s0217979203019617.

Full text

Abstract:

The deformation of the surface of epoxy resin plates with an embedded linear shape-memory alloy (SMA) wire as an actuator in smart structure members is measured as a function of the duration of the supply of electric current to the SMA wire, using a digital image correlation technique. Results show that the two-dimensional deformation of the plate surface can be measured, and that the maximum deformation of the plate surface can be obtained on both sides of a crack and increases with the duration of the current supply. Therefore, the deformation of the plate surface measured using the digital image correlation technique suggests the possibility of its application in the prediction of crack closure in epoxy resin plates with embedded SMA wires heated by supplying electric current.

APA, Harvard, Vancouver, ISO, and other styles

37

Awan, Z. A. "Surface impedance properties of a wire grid embedded in a chiral medium." International Journal of Microwave and Wireless Technologies 12, no. 1 (July 9, 2019): 58–65. http://dx.doi.org/10.1017/s1759078719000953.

Full text

Abstract:

AbstractThe surface impedance characteristics of a wire grid composed of infinitely long parallel conducting wires embedded in lossless and lossy frequency-dispersive chiral background media have been investigated. Using wavefield decomposition approach for a chiral background and with the application of impedance boundary conditions for a wire grid, an analytic expression for the surface impedance of a wire grid with a chiral background has been derived. It is shown that the surface impedance magnitude of a wire grid with chiral nihility background is close to zero and almost independent of incident polar angles. A strong chiral background significantly enhances the surface impedance magnitude of a wire grid for incident polar angles closer to right angle as compared to the free space background. The same electromagnetic appearance of a wire grid with frequency-dispersive chiral and free space background media at some critical frequency has also been discussed which may find applications in electromagnetic illusions. It is also shown that if the value of incident polar angles are closer to right angle then the impedance magnitude of a wire grid embedded in the realistic chiral background is smaller as compared to the same wire grid when placed in the free space background.

APA, Harvard, Vancouver, ISO, and other styles

38

Mu, Haibao, Yitong Yao, Shu Zhang, Guangyu Sun, Baohong Guo, Falun Song, Yanlin Cheng, and Guanjun Zhang. "Metal-wire-embedded alumina insulating material using micro- and nanoscale 3D printing for surface flashover mitigation in a vacuum." Journal of Physics D: Applied Physics 55, no. 17 (January 31, 2022): 175201. http://dx.doi.org/10.1088/1361-6463/ac4454.

Full text

Abstract:

Abstract A micro- and nanoscale 3D printing technique is applied to fabricate a functional insulating material that mitigates surface discharge in a vacuum based on microscopic electron multipactor suppression. The proposed alumina ceramic insulator design consists of surface-embedded thin metal wires that introduce a local gradient of secondary electron emission (SEE) yield, such that the trajectories of multipactor electrons are distorted by accumulated negative surface charge and the SEE avalanche across the insulator surface becomes intermittent. Considerable increases of surface flashover threshold and surface charging reduction are verified by the experiment. Also, additional efforts are made to determine the optimal size and spatial distribution of the metal wire. A convex-shape flashover voltage trace is observed when increasing the width of the wire, suggesting a trade-off between the multipactor mitigation and the insulator strength. The wire’s position between the adjacent cathode triple junction and the middle of the insulator is proved to be favorable for flashover mitigation. The physical details of surface flashover mitigation by the proposed insulator design are revealed by an ab initio particle-in-cell simulation code, corroborating the experiment from a microscopic aspect.

APA, Harvard, Vancouver, ISO, and other styles

39

Mirzaei, A. H., M. M. Shokrieh, and A. Saeedi. "Fatigue behavior of laminated composites with embedded SMA wires." Composite Structures 293 (August 2022): 115753. http://dx.doi.org/10.1016/j.compstruct.2022.115753.

Full text

APA, Harvard, Vancouver, ISO, and other styles

40

Schrooten, Jan, Véronique Michaud, John Parthenios, Georgios C Psarras, Costas Galiotis, Rolf Gotthardt, Jan-Anders Månson, and Jan Van Humbeeck. "Progress on Composites with Embedded Shape Memory Alloy Wires." MATERIALS TRANSACTIONS 43, no. 5 (2002): 961–73. http://dx.doi.org/10.2320/matertrans.43.961.

Full text

APA, Harvard, Vancouver, ISO, and other styles

41

Maranganti, R., and P. Sharma. "Strain Field Calculations in Embedded Quantum Dots and Wires." Journal of Computational and Theoretical Nanoscience 4, no. 4 (June 1, 2007): 715–38. http://dx.doi.org/10.1166/jctn.2007.2359.

Full text

APA, Harvard, Vancouver, ISO, and other styles

42

Appelt, Bernd K., Bruce Su, Uno Yen, and Kay Essig. "Embedded Die Substrates for Power Applications." International Symposium on Microelectronics 2012, no. 1 (January 1, 2012): 001143–48. http://dx.doi.org/10.4071/isom-2012-thp44.

Full text

Abstract:

Historically, power die like MOSFETs have been packaged on lead frames using wire bonds as interconnects. To facilitate current carrying requirements, thick wires and sometimes also clips were used, to handle the total electrical and thermal conductivity requirements. As die are being thinned, it has become possible to take advantage of new electrical designs and locate source and drain on opposite sides of the die. Such die can now be easily packaged by embedding the power die in organic substrates. The die is bonded on a Cu pad and covered by prepreg and copper foil during lamination. Source, drain and gate pads are accessed from the top side with laser vias and filled with plated copper. Finally, the top side is patterned and protected with solder mask. Electrical and thermal modeling data can demonstrate the performance efficiency while reducing the form factor in accordance with the miniaturization requirements of mobile applications. Aside from single die packages, more advanced packages can be built containing multiple power die and controller die. The basic process flow remains the same but does require some adaptation. If so desired, additional components may be assembled on top of the embedded die package leading to further integration and miniaturization.

APA, Harvard, Vancouver, ISO, and other styles

43

Böttcher, Lars, S. Karaszkiewicz, D. Manessis, Eckart Hoene, and A. Ostmann. "Next Generation High Power Electronic Modules Based on Embedded Power Semiconductors." Additional Conferences (Device Packaging, HiTEC, HiTEN, and CICMT) 2014, DPC (January 1, 2014): 000694–719. http://dx.doi.org/10.4071/2014dpc-tp12.

Full text

Abstract:

The spectrum of conventional power electronics packaging reaches from SMD packages for power chips to large power modules. In most of these packages the power semiconductors are connected by bond wires, resulting in large resistances and parasitic inductances. Power chip packages have to carry semiconductors with increasing current densities. Conventional wire bonds are limiting their performance. Today's power modules are based on DCB (Direct Copper bonded) ceramic substrates. IGBT switches are mounted onto the ceramic and their top side contacts are connected by thick Al wires. This allows one wiring layer only and makes an integration of driver chips very difficult. Additionally bond wires result in a high stray inductance which limits the switching frequency. Especially for the use of ultra-fast switching semiconductors, like SiC and GaN, it is very difficult to realize low inductive packages. The embedding of chips offers a solution for many of the problems in power chip packages and power modules. While chip embedding was an academic exercise a decade ago, it is now an industrial solution. A huge advantage of packaging using PCB technology is the cost-effective processing on large panel. Furthermore embedded packages and modules allow either double-side cooling or 3D assembly of components like capacitors, gate drivers or controllers. The advanced results of research projects will be discussed in the paper. An ultra-low inductance power module with SiC switches at 20 A / 600 V has been realized and characterized. The DC link inductance of the module was 0,8 nH only. These results sparked a huge interest in currently starting follow up projects creating package for fast switches. In a further project power modules for automotive power inverters for motor control are under development. As a project demonstrator, a 10 kW module with IGBTs and diodes at 400 V / 500 A, was manufactured. This demonstrator is based on high power PCB technology and was fully characterized; the results will be presented in detail. Recently started research projects will face the challenges of MW solar inverters at 1000 A and 1000 V, using SiC semiconductors as switches. First concepts will be presented as an outlook.

APA, Harvard, Vancouver, ISO, and other styles

44

Muwafaq Mohmmed Ali, Omer, Rawaa Hamid Mohammed Al-Kalali, and Ethar Mohamed Mahdi Mubarak. "Vibrational Analysis of Composite Beam Embedded with Nitinol Shape Memory Alloy Wires." International Journal of Engineering & Technology 7, no. 3.4 (June 25, 2018): 143. http://dx.doi.org/10.14419/ijet.v7i3.4.16763.

Full text

Abstract:

In this paper, laminated composite materials were hybridized with fibers (E-glass) and shape memory alloy wires which considered a smart material. The effect of changing frequency on the (acceleration- frequency) response curve, the damping ratio of the vibration modes, the natural frequencies of the vibration mode, the effect of shape memory alloy wires number on the damping characteristics were studied. Hand lay-up technique was used to prepare the specimens, epoxy resin type was used as a matrix reinforced by fiber, E-glass. The specimens were manufactured by stacking 2 layers of fibers. Shape memory alloy, type Nitinol (nickel-titanium) having a diameter (1 and 2mm), was used to manufacture the specimens by embedding (1,2 and 3) wires into epoxy. Experimentally, the acceleration- frequency response curve was plotted for the vibration modes, this curve was used to measure the natural frequencies of the vibration modes and calculate the damping ratio of the vibration modes. ANSYS 15- APDL was used to determine the mode shape and find the natural frequencies of the vibration modes then compared with the experimental results. The results illustrated that, for all specimens increasing the natural frequency leads to decreasing the damping ratio. Increasing the number of shape memory alloy wires leads to increase the values of the damping ratio of the vibration modes and the natural frequencies of the vibration modes at room temperature.

APA, Harvard, Vancouver, ISO, and other styles

45

Kanchikere, Jayanna, A. K. Ghosh, and Kalyankumar Kalyankumar. "Embedded Patient Monitoring System." International Journal of Power Electronics and Drive Systems (IJPEDS) 10, no. 1 (March 1, 2019): 388. http://dx.doi.org/10.11591/ijpeds.v10.i1.pp388-397.

Full text

Abstract:

<p>ICU remains for Intensive Care Unit, a place in the recuperating office where wiped out patients are checked eagerly. Commonly, the patient-staff extent is low and the LIFE-SAVING EQUIPMENT used is outstandingly bleeding edge Generally ICU is a healing facility for course of action of genuine nursing and remedial consideration of essentially wiped out patients, depicted by high bore and measure of unending nursing and restorative supervision and by use of cutting edge checking and resuscitative equipment The patients in the ICU require a predictable seeing of their Temperature and pulse circulatory strain. This undertaking is a working model, which wires sensors to evaluate imperative parameters specifically the Temperature, Respiratory temperature and Heart Beat. The sensors are interfaced to PC, with the objective that the condition of a patient can be explored by masters in any bit of the center wherever they are. At whatever point there is a variety from the standard felt by the patient, the particular patient will give an alert movement, by which the pro can race to the patient. Despite when the patient is in a careless condition, each one of the parameters will be identified and pro will be admonished, thusly it diminishes master's remaining task at hand and besides gives more correct results .Our endeavor is a working model which wires sensors to measure each one of these parameters like body temperature, Respiratory Temp and Heart Beat rate and trade it to the PC, with the objective that the patient condition can be examined to by authorities in any bit of the recuperating focus wherever they are. In this way it decreases experts work stack and besides gives more exact results, wherever there is a variety from the standard felt by the patient, we have in like manner combined saline watching system which gives an alert when the saline container going to cleanse.</p>

APA, Harvard, Vancouver, ISO, and other styles

46

Wepner, Lena, Harald Andreas Färber, Andreas Jaensch, Anna Weber, Florian Heuser, Ludger Keilig, Lamia Singer, and Christoph Peter Bourauel. "In Vitro Ion Release of Wires in Removable Orthodontic Appliances." Materials 14, no. 12 (June 19, 2021): 3402. http://dx.doi.org/10.3390/ma14123402.

Full text

Abstract:

Various orthodontic wire compositions and configurations are present on the market for removable appliances; however, there have still been only few studies focusing on the effect of resin color and additives such as glitter on corrosion of metallic wires under different conditions. Thus, the aim of the study was to compare concentrations of released ions (aluminium, chromium, nickel) in a corrosive medium under three different conditions: non-loaded wires, loaded wires, and non-loaded wires treated with Kukis® cleaning tablets. Six different wires made of three types of steel alloy were embedded in PMMA resin leaving one centimetre of each wire emerging from the resin to come into contact with the corrosive medium. Glitter particles were added to half of the produced test specimens. For the unloaded test series, five specimens of each group were covered in a petri dish with 50 mL of corrosive medium (pH 2.3) following EN-ISO 10271 for seven days at 37 °C. The wires for the mechanically loaded test specimens overlapped the resin by 5 cm and were clamped into a time-switched electric drive for a defined period of time before the samples were taken after a testing time of 7 days. In the third group, unloaded test specimens were transferred from their petri dishes into the prepared Kukis® solution every 24 h before being stored in the corrosive medium. Inductively coupled plasma mass spectrometry (ICP-MS) was used to quantify the specific ions in the corrosive solution. Statistical analysis showed that the mechanical loading of all wires could significantly raise the diffusion of ions into the corrosive medium. The colour of the resin did not affect the concentration of the released ions. The Kukis® cleaning tabs could not lower the corrosion of the tested metals, as some of the wires were corroded even more using the brace cleanser. Glitter-containing test specimens showed significantly higher amounts of aluminium. Mechanical loading as well as the presence of glitter particles in the resin significantly affected ion concentrations.

APA, Harvard, Vancouver, ISO, and other styles

47

Choi, Sup, Jung Ju Lee, and Dong Chun Lee. "Thermal Buckling of Laminated Composite Beams with Embedded Shape Memory Alloy Actuators." Journal of Composite Materials 34, no. 18 (September 2000): 1529–47. http://dx.doi.org/10.1106/gxxu-bevy-d4u0-fy5f.

Full text

Abstract:

In this paper, the thermal buckling and postbuckling behaviours of a composite beam with embedded shape memory alloy (SMA) wires are investigated experimentally and analytically. For the purpose of enhancing the critical buckling temperature and reduction of the lateral deflection on thermal buckling and postbuckling, the characteristics of thermal buckling are investigated through the use of the shape recovery force. The results of thermal buckling tests using uniformly heated and clamped composite beam specimens with embedded SMA wire actuators are discussed. The temperature-load-deflection behaviour records present quantitatively how the shape recovery force affects the thermal buckling behaviour. For this experiment, we considered the initial geometric imperfections, the slenderness ratio of the beam and the embedding position of the SMA wire actuators. The experimental results show that the shape recovery force reduces the thermal expansion of the composite laminated beam. This results in an increase of the critical buckling temperature and a reduction of the lateral deflection of the beams.

APA, Harvard, Vancouver, ISO, and other styles

48

Grenier, Vincent, Sylvain Finot, Lucie Valera, Joël Eymery, Gwénolé Jacopin, and Christophe Durand. "UV-A to UV-B electroluminescence of core-shell GaN/AlGaN wire heterostructures." Applied Physics Letters 121, no. 13 (September 26, 2022): 131102. http://dx.doi.org/10.1063/5.0101591.

Full text

Abstract:

Core-shell GaN/AlGaN multiple quantum wells (MQWs) embedded in a p–n junction are integrated on the upper part of GaN microwires grown by silane-assisted metal organic vapor phase epitaxy. Dispersed wires are then contacted by electron beam induced deposition for fabrication of single wire UV-LED devices. Rectifying diode-like behavior is first demonstrated for both GaN and GaN/AlGaN p-n junctions without a MQW active region. A weak leakage current in the GaN/AlGaN core-shell heterostructure is attributed to an additional conduction path along wire sidewalls. Electroluminescence at 340 nm in UV-A is demonstrated using a GaN (2.6 nm)/Al0.3Ga0.7N (3 nm) heterostructure embedded in a GaN/Al0.3Ga0.7N p–n junction. This value is even decreased to 310 nm by reducing the well thickness to 0.9 nm and increasing the Al-content of barriers (up to 60%) integrated in the GaN/Al0.3Ga0.7N p–n junction. This work demonstrates UV-B emission based on single wire core-shell UV-LEDs.

APA, Harvard, Vancouver, ISO, and other styles

49

Gupta, K. "Critical Speed Analysis of Fibre Reinforced Composite Rotor Embedded with Shape Memory Alloy Wires." International Journal of Rotating Machinery 6, no. 3 (2000): 201–13. http://dx.doi.org/10.1155/s1023621x00000191.

Full text

Abstract:

In the present analysis, the fundamental natural frequency of a Jeffcott and a two-mass rotor with fibre reinforced composite shaft embedded with shape memory alloy (SMA) wires is evaluated by Rayleigh's procedure. The flexibility of rotor supports is taken into account. The effect of three factors, either singly or in combination with each other, on rotor critical speed is studied. The three factors are: (i) increase in Young's modulus of SMA (NITINOL) wires when activated, (ii) tension in wires because of phase recovery stresses, and (iii) variation of support stiffness by three times because of activation of SMA in rotor supports. It is shown by numerical examples that substantial variation in rotor critical speeds can be achieved by a combination of these factors which can be effectively used to avoid resonance during rotor coast up/down.

APA, Harvard, Vancouver, ISO, and other styles

50

Soltanieh, Ghazaleh, M. Shariyat, and Mohammad Z. Kabir. "Influence of the 3D material tailoring on snap-through and snap-back post-buckling behaviors of steel-wire-reinforced hybrid 3D graded orthotropic shallow cylindrical panels." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 233, no. 2 (February 28, 2018): 685–701. http://dx.doi.org/10.1177/0954406218760062.

Full text

Abstract:

Simultaneous application of composite layers and steel bars/wires may considerably increase buckling strength of the civil structures. In the present paper, influence of the material heterogeneity on snap-through and snap-back post-buckling behaviors of the steel-wire-reinforced hybrid functionally graded orthotropic shallow cylindrical panels is investigated. In this regard, various arrangements are adopted for the steel-wires to constitute 3D (simultaneous radial, circumferential, and axial) gradations of the materials within some layers in addition to using some traditional composite layers in between. The non-linear governing equations of post-buckling are derived based on the principle of minimum potential energy. Sanders’ shell theory is utilized to ensure that the results are reliable in the deep post-buckling region. A nonlinear finite element scheme is employed to trace the post-buckling paths using the modified arc-length method. Finally, some parametric studies in terms of material arrangement, size of the embedded steel wires, the overall lamination scheme, and geometric parameters of the shell are performed. Results emphasize the significant effects of the steel wires on the post-buckling strength and indicate the advantage of using steel fibers with exponential or uniform longitudinal distributions and linear transverse distribution, for weight optimization.

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Embedded wires'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles