Wire Resistance Research Articles

The erosion resistance of tool alloys in foundry melt the Zamak 4 - 1

The paper considers the resistance against erosion dissolution in the melt of foundry Zamak 4 - 1 die steels used for press machine parts manufacturing for injection molding, and hard alloys system WC - Co. It is established that the solubility in the melt Zamak - 4 - 1 steel of 4H5MFS and DI - 22 are promising for the parts fabrication of metal-wire casting machines of CLT and IDRA types. A significant reserve to increase the resistance of metal wires is the use of cast steel, as well as in electroslag and electro-beam remelting options. Metal-ceramic alloy doped with chromium VK25H may be recommended for reinforcement of heavily loaded parts of the press-nodes of hot casting machines under pressure.

Impact of Wire Geometry on Interconnect <italic>RC</italic> and Circuit Delay

We investigate the impact of wire geometry on the resistance, capacitance, and RC delay of Cu/low-k damascene interconnects for fixed line-to-line pitch. The resistance is computed by applying a semiempirical resistivity model, calibrated to Cu damascene wires, integrated with a Ru-based liner, currently investigated for the 7 nm logic technology node. The capacitance is simulated by means of a 2D field solver (Raphael) by Synopsys. The impact of line dimensions is analyzed for the case of 32 nm pitch interconnects, which are representative of the 7 nm logic technology node. We show that for aspect ratios greater than 1, the resistance is more sensitive to variations of the line width rather than of the line height, because of the higher surface scattering induced by the sidewall interfaces, which are closer to each other compared with the top and bottom interfaces. For capacitance, low-k sidewall damage exacerbates capacitance sensitivity to line dimensions and, for typical interconnect schemes, the impact of line width variations dominates over variations of the line height. We demonstrate that for a given pitch and dielectric stack height, the RC delay can be significantly reduced by targeting wider and deeper damascene trenches, that is, by trading capacitance for resistance, and that an optimal wire geometry for RC delay minimization exists. In addition, we show that a given RC delay can be achieved with several geometries and, therefore, R and C pairs, which represents a useful degree of freedom for designers to optimize system-level performance. As an application, we analyze a possible 7 nm technology scenario and show that wide and deep damascene trenches can mitigate the impact of the increased wire resistance on circuit delay.

DESIGN AND ANALYSIS OF FOG REMOVAL SYSTEM FOR HELMET

This paper deals with the design and analysis of fog removal system for motorcycle helmet. The system consists mainly of a resistive wire for thermal convection between the heating element and the helmet visor. When electrical voltage is applied to the heating element, it will create a temperature difference across the helmet visor. The model is designed and thermal analysis has been carried out using Ansys. The analysis shows efficient mist removal from the visor in few minutes.

Critical Performance Analysis of HTS Magnet Wires Using an Induced Current-Based Measurement System

Studies on wide and stacked high-temperature superconducting (HTS) wires aim to increase the critical current of the wires. This paper describes the design and fabrication of an induced current-based performance measurement system and a critical performance analysis of HTS magnet wires using this system. In the experiment, the induced current, critical current, and joint resistance of stacked HTS wires under charge and discharge conditions were investigated. The results obtained were compared with those achieved using the four-terminal method, which is the conventional measurement method. The measurement system and the results of the critical performance analysis of the HTS wire are discussed in detail.

Single‐phase to ground fault current distribution in transmission system based on the improved double‐side elimination method

In order to calculate the fault current distribution when a single‐phase to ground fault occurs in a transmission system with asymmetric parameters, this paper proposes an improvement on the traditional double‐side elimination method based on the phase component model. The improved double‐elimination method widens the range of the original method to the situation of multiple overhead ground wires and double power sources at both terminals. From the fault point, it divides the system into the left and right networks. Taking the left network as an example, the equations of all spans are formed. Then, the forward–backward recursive process of the theory is demonstrated. By optimizing the matrix calculation process, the calculation model for computers is formed, which can easily calculate the fault current on phase wires and overhead ground wires when a single‐phase to ground fault occurs. By comparing the results from this theory and the results from the EMTP simulation software, the correctness of the theory is established. Furthermore, in this paper we give a detailed discussion on the influence of tower grounding resistance and overhead ground wire operation mode on the fault current distribution. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.

A Novel Two-Wire Fast Readout Approach for Suppressing Cable Crosstalk in a Tactile Resistive Sensor Array.

For suppressing the crosstalk problem due to wire resistances and contacted resistances of the long flexible cables in tactile sensing systems, we present a novel two-wire fast readout approach for the two-dimensional resistive sensor array in shared row-column fashion. In the approach, two wires are used for every driving electrode and every sampling electrode in the resistive sensor array. The approach with a high readout rate, though it requires a large number of wires and many sampling channels, solves the cable crosstalk problem. We also verified the approach’s performance with Multisim simulations and actual experiments.

Buffering Carbon Nanotube Interconnects Considering Inductive Effects

While copper interconnect scaling is approaching its fundamental physical limit, increasing wire resistivity and delay have greatly limited the circuit miniaturization. The emerging carbon nanotube (CNT) interconnects, especially single-walled CNTs (SWCNTs) bundle interconnects, have become a promising replacement material. Nevertheless, physical design optimization techniques are still needed to allow them achieving the desired performances. While the preliminary conference version of this work [L. Liu, Y. Zhou and S. Hu, Proc. IEEE Computer Society Annual Symp. on VLSI (ISVLSI), 2014] designs the first timing driven buffer insertion technique for SWCNT interconnects, it only considers resistive and capacitive effects but not inductive effects. Although inductance could be negligible for prevailing CNT-based circuit designs, it becomes important when designing ultra-high performance chips in the future. Thus, this paper considers buffering inductive bundled SWCNTs interconnects through developing a dynamic programming algorithm for buffer insertion using the RLC tree delay model. Our experiments demonstrate that bundled SWCNTs interconnect-based buffering can effectively reduce the delay by over [Formula: see text] when inductive effects are considered. With the same timing constraint, bundled SWCNTs interconnect-based buffering can save over 20% buffer area compared to copper interconnect based buffering, while still running about [Formula: see text] faster.

A combination of high electrical conductivity and mechanical strength in AA1070 commercially pure aluminum wires fabricated by KoBo extrusion

Abstract In this work, the effect of KoBo extrusion process parameters on the extrusion force, microstructure, mechanical properties and electrical resistivity of wires fabricated from AA1070 commercially pure aluminum, is analyzed. It is found that applied parameters of the KoBo extrusion process have a strong impact on changes in the extrusion force. The smallest variation of the extrusion force was recorded for the KoBo extrusion conducted with a small oscillation angle and a high extrusion rate. The relatively small alteration of the extrusion force results in a more homogeneous microstructure and mechanical properties of the wires. As compared to the material in the annealed state, the KoBo extruded wires exhibit almost two-fold higher ultimate tensile strength and only a slightly lowered electrical conductivity. The best combination of electrical conductivity and mechanical strength was 60.3 % International Annealed Copper Standard and ultimate tensile strength of 152 MPa, respectively. These results are highly competitive to those reported for AA1070 aluminum subjected to other continuous plastic deformation methods (e. g. the cryorolling combined with a heat treatment). A high electrical conductivity and enhanced mechanical properties (in respect to the as annealed material), clearly indicate that the KoBo extruded AA1070 wires are potentially useful for moderately loaded electrical engineering applications.

Torque resistance of different stainless steel wires commonly used for fixed retainers in orthodontics.

"Torque resistance of different stainless steel wires commonly used for fixed retainers in orthodontics." Journal of Orthodontics, 43(2), pp. 90–91

Torque resistance of different stainless steel wires commonly used for fixed retainers in orthodontics.

Movements of teeth splinted by fixed retention wires after orthodontic treatment have been observed. The aetiological factors for these movements are unknown. The aim of this in vitro study was to compare the resistance to torque of different stainless steel wires commonly used for fixed retainers in orthodontics. Torquing moments acting on a retainer wire were measured in a mechanical force testing system by applying buccal crown torque to an upper lateral incisor in both a 3-teeth and in a 2-teeth setup. Seven stainless steel wires with different shape, type (plain, braided, coaxial, or chain) and dimensions were selected for this study. For a torquing angle of 16.2° in the 3-teeth setup torsion moments can vary between 390 cNmm and 3299 cNmm depending on the retainer wire. For the 2-teeth setup the torsion moments are much smaller. Exposure to the flame of a butane-gas torch for 10 seconds to anneal the wire reduces the stiffness of the retainer wire. Clinicians must select wires for fixed retainers very carefully since the difference in resistance to torque is large. A high level of torque control can be achieved with a plain 0.016 × 0.016-inch or a braided 0.016 × 0.022-inch stainless steel wire. A tooth attached by a retainer wire to only one neighbouring tooth is less resistant to torque than a tooth connected to two neighbouring teeth. Annealing a retainer wire with a flame reduces the stiffness of the wire markedly and can lead to a non-uniform and non-reproducible effect.

Underwater Electrical Explosion of Wires and Wire Arrays and Generation of Converging Shock Waves

A brief review of the results obtained in recent research of underwater electrical explosions of wires and wire arrays using microsecond-, submicrosecond-, and nanosecond-timescale high-current generators is presented. In a microsecond-timescale wire explosion, good agreement was attained between the results of experiments and the results of magnetohydrodynamic calculations coupled with equations of state (EOS) and modern conductivity models. Conversely, in a nanosecond-timescale wire explosion, the wire resistance and the EOS were modified in order to fit experimental data. In experiments with cylindrical and spherical wire arrays, generation of a converging shock wave (SW) was demonstrated allowing formation of an extreme state of water in the vicinity of either the axis or the origin of the SW’s implosion. In addition, it is shown that SW convergence in superspherical geometry allows one to achieve larger values of pressure, density, and temperature of water in the vicinity of the axis of convergence than in the case of a spherical implosion. The results of experiments and numerical analysis showed that a cylindrical SW keeps its symmetry along the main path of its convergence. In addition, it is shown that underwater electrical explosion of an X-pinch wire configuration and a cone wire array allows one to generate fast jets of metal and water, respectively, without using chemical explosions.

Entrainment of two thermoacoustic engines

In order to build more powerful sources of sound for energy conversion, the synchronization of two thermoacoustic heat engines has been studied. Experiments were performed on engines in the acoustic frequency range of 2.6 kHz and also on very small engines in the ultrasonic range of 24 kHz. In both cases, the engines were mounted on a cylindrical cavity, and they were coupled mainly by the acoustic field in the surrounding air at one atmosphere. They were driven by heaters of resistance wire in contact with the hot heat exchanger. At a specific coupling between the 2.6 kHz, engines' synchronization occurred, and also for the 24 kHz devices; frequency pulling in each pair of engines led to a common frequency in each set, i.e., in-phase synchronization. The strength of the synchronization was determined as a function of detuning of engines. Mutual entrainment was observed at the onset of oscillations and this is attributed to drive by fluctuations. Moreover, as a result of synchronization, the critical temperature gradient for onset of oscillations was reduced from that of the individual values. Delays between two oscillators in the start up led to quenching of the generated sound output ( oscillation “death” of Rayleigh).

Impact of Sterilisation and Strain Hardening in Drawing Process on Resistance to Electrochemical Corrosion of Wires Intended in Cardiology

The study presents results of tests of impact of work hardening in cold drawing process, surface treatment and sterilisation on resistance to electrochemical corrosion of wires made of stainless steel X2CrNiMo 17-12-2 intended for cardiology. Potentiodynamic tests were performed on the ground of registered anodic polarisation curves in artificial plasma solution. Static uniaxial tension test made the ground for determination of strength characteristics of wires and the flow curve. Functions presenting the change of polarisation resistance according to strain applied in drawing process were selected. Test results show deterioration of corrosion properties of wires with work hardening. Surface modification of passivated surface caused increase of resistance of stainless steel wires to electrochemical corrosion, whereas sterilisation with pressurised water steam deteriorated that resistance.

Effects of nanostructured, diamondlike, carbon coating and nitrocarburizing on the frictional properties and biocompatibility of orthodontic stainless steel wires.

To evaluate and compare the effects of nanostructured, diamondlike, carbon (DLC) coating and nitrocarburizing on the frictional properties and biocompatibility of orthodontic stainless steel archwires. Plasma-enhanced chemical vapor deposition technology was applied to coat DLC films onto the surface of austenitic stainless steel wires, and salt-bath nitrocarburizing technology was employed to achieve surface hardening of other wires. Surface and cross-sectional characteristics, microhardness, modulus of elasticity, friction resistance, corrosion resistance, and cell toxicity of the modified and control wires were analyzed. The surfaces of the DLC-coated and nitrocarburized wires were both smooth and even. Compared with the control, the DLC-coated wires were increased in surface hardness 1.46 times, decreased in elastic modulus, reduced in kinetic friction coefficient by 40.71%, and decreased in corrosion current density by two orders of magnitude. The nitrocarburized wire was increased in surface hardness 2.39 times, exhibited an unchanged elastic modulus, demonstrated a decrease in maximum static friction force of 22.2%, and rose in corrosion current density two orders of magnitude. Cytotoxicity tests revealed no significant toxicity associated with the modified wires. DLC coating and nitrocarburizing significantly improved the surface hardness of the wires, reduced friction, and exhibited good biocompatibility. The nanostructured DLC coating provided excellent corrosion resistance and good elasticity, and while the nitrocarburizing technique substantially improved frictional properties, it reduced the corrosion resistance of the stainless steel wires to a lesser extent.

A smart orthopedic compression device based on a polymeric stress memory actuator

In current practice of compression therapy, there has been a challenge of compression controlling and need for multiple devices to achieve different functions. Herein, the potential of a thermal-sensitive memory polymer, namely, polyurethane (MPU), is explored in designing a prototype that acts as a flexible bandage system to provide dual benefits (heat and pressure) simultaneously for a desired compression. After preconditioning, the thermomechanical behavior of the MPU becomes repeatable and consistent, which can be programmed to remember (store) and retrieve reversibly a prescribed internal stress, responsive to an external stimulus around its transition temperature (Ttrans). The smart bandage system is then built using the MPU actuator which integrates electric resistive wires as both a heat source for thermal therapy and stimulus for trigger control. The compression can also be easily switched between static and dynamic (massage) modes using a pro-set thermal stimulus. This paper also addresses several challenging issues and design considerations for the prototype. Theoretical analyses have been applied to predict the device performance, showing excellent agreement with experimental results. This work sheds insights for broadening the applications of stress memory and for engineering smart products needing stimulus responsive forces such as dynamic cushions, pressure garment and electronic actuators.

Cable Crosstalk Suppression with Two-Wire Voltage Feedback Method for Resistive Sensor Array.

Using a long, flexible test cable connected with a one-wire voltage feedback circuit, a resistive tactile sensor in a shared row-column fashion exhibited flexibility in robotic operations but suffered from crosstalk caused by the connected cable due to its wire resistances and its contacted resistances. Firstly, we designed a new non-scanned driving-electrode (VF-NSDE) circuit using two wires for every row line and every column line to reduce the crosstalk caused by the connected cables in the circuit. Then, an equivalent resistance expression of the element being tested (EBT) for the two-wire VF-NSDE circuit was analytically derived. Following this, the one-wire VF-NSDE circuit and the two-wire VF-NSDE circuit were evaluated by simulation experiments. Finally, positive features of the proposed method were verified with the experiments of a two-wire VF-NSDE prototype circuit. The experiment results show that the two-wire VF-NSDE circuit can greatly reduce the crosstalk error caused by the cables in the 2-D networked resistive sensor array.

Fabrication of TiO2 coated metallic wires by the sol–gel technique as a humidity sensor

An humidity sensor based on a TiO2 coated metallic wire has been prepared by the sol–gel technique. TiO2 is deposited on a commercial Fe-based wire by dip-coating from alcoholic solutions of titanium tetraisopropylalkoxide. Several experimental conditions are studied as: the acid activation of the wire surface, the interaction of the wire with the titanium solution and the drying and calcination steps. The coating process is repeated four times to fabricate the final sensor. A capacitive humidity sensor was developed by sputtering deposition of a semicylindrical gold electrode on the TiO2 coated wire resulting from the coating processes. The sensing principle is based in the changes of the complex impedance of the capacitive device as a result of the humidity dependence of the electric permittivity of the TiO2 ceramic coating. The functionally of the sensor device can be expanded by the simultaneous characterization of the temperature dependence of the electric resistance of the inner metallic wire.

Valence Band Dependent Charge Transport in Bulk Molecular Electronic Devices Incorporating Highly Conjugated Multi-[(Porphinato)Metal] Oligomers.

Molecular electronics offers the potential to control device functions through the fundamental electronic properties of individual molecules, but realization of such possibilities is typically frustrated when such specialized molecules are integrated into a larger area device. Here we utilize highly conjugated (porphinato)metal-based oligomers (PM(n) structures) as molecular wire components of nanotransfer printed (nTP) molecular junctions; electrical characterization of these "bulk" nTP devices highlights device resistances that depend on PM(n) wire length. Device resistance measurements, determined as a function of PM(n) molecular length, were utilized to evaluate the magnitude of a phenomenological β corresponding to the resistance decay parameter across the barrier; these data show that the magnitude of this β value is modulated via porphyrin macrocycle central metal atom substitution [β(PZn(n); 0.065 Å(-1)) < β(PCu(n); 0.132 Å(-1)) < β(PNi(n); 0.176 Å(-1))]. Cyclic voltammetric data, and ultraviolet photoelectron spectroscopic studies carried out at gold surfaces, demonstrate that these nTP device resistances track with the valence band energy levels of the PM(n) wire, which were modulated via porphyrin macrocycle central metal atom substitution. This study demonstrates the ability to fabricate "bulk" and scalable electronic devices in which function derives from the electronic properties of discrete single molecules, and underscores how a critical device function--wire resistance--may be straightforwardly engineered by PM(n) molecular composition.

Microstructure and degradation properties of C-containing composite coatings on magnesium alloy wires treated with micro-arc oxidation

Abstract To improve the corrosion resistance of micro-arc oxidation (MAO) treated Mg alloy wires, carbon (C) nanoparticles were added to the silicate electrolyte to fabricate C-containing composite coatings. Comparisons of microstructure, corrosion resistance and mechanical properties of uncoated wires, MAO-C-free coated wires and MAO-C coated wires were performed. The results indicated that the surface layers of Mg alloy wires treated with MAO were primarily composed of MgO and Mg 2 SiO 4 phases and demonstrated porous morphologies. The C nanoparticles in the electrolyte were capable of incorporating into composite coatings, forming a dense composite coating microstructure and resulting in the formation of a small amount of MgAlO 4 and Mg 3 SiO 4 F 2 , which improve corrosion resistance in static and dynamic immersion environments. Measurements of mechanical properties demonstrated that the MAO-C coated wires retained a high tensile strength of 180 MPa, even after dynamic immersion for 50 days, and possessed better corrosion resistance than the wires coated with MAO-C-free coating. The effects of shear stress and localized environment changes resulting from the flowing corrosive media were proposed as two mechanisms that accelerated corrosion in a dynamic immersion environment.

Rheological Resistance of CuAg15 Alloy Wires

The paper presents the results of studies on obtaining the alloy and generating a set of very high mechanical and electrical properties of wires. The paper also presents the results of testing the rheological resistance in the form of stress relaxation tests carried out on the wires after various thermomechanical treatment processes. The optimum parameters of the thermo-mechanical treatment of the alloy were determined, enabling obtaining the most favorable mechanical and electrical properties of wires. The relationships of the influence of the material and its deformation on the changes in the mechanical and electrical properties of wires were determined. In addition, a microstructural analysis was carried out of casts and wires using scanning electron microscopy. Cast material was subject to observation and the material at successive stages of heat treatment.