Journal articles: 'Powder wires'

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Talic, Nabeel F. "Effect of Air-powder Polishing on the Surface Topography of Orthodontic Stainless Steel Wires." World Journal of Dentistry 8, no. 4 (2017): 262–66. http://dx.doi.org/10.5005/jp-journals-10015-1448.

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ABSTRACT Aim The aim of this study was to examine the effect of in vivo air-powder polishing on the surface roughness and topography of aged orthodontic stainless steel arch wires. Materials and methods A total of 20 stainless steel arch wires were used in this study. Ten wires (experimental) were aged and exposed to air-powder polishing, and 10 wires asreceived from the manufacturer served as the controls. The experimental group of wires was aged in the patient's oral cavity for an average of 5.3 ± 2.7 months. An air-powder polishing system was used to remove external stains and plaque deposits. The powder was sodium bicarbonate. The surface topography measurements were performed using an optical profilometer. Following the profilometer analysis, a scanning electron microscope (SEM) was used to evaluate the experimental and control arch wires. Results The average roughness (Sa) of the experimental upper and lower surfaces exposed to air-powder polishing was significantly higher than the control arch wires (p < 0.01). The root mean square of the surface topography (Sq) and the 10-point height of the surface topography (Sz) were significantly higher on the upper and lower surfaces of the experimental arch wires compared with the controls (p < 0.05 and <0.01 respectively). The SEM photomicrographs of the experimental and control arch wires indicated that the experimental arch wires were pitted and filled with surface impurities. Conclusion An air-powder polishing system using sodium bicarbonate powder alters the surface topography and increases the surface roughness of aged orthodontic arch wires in vitro. Clinical significance The air-powder polishing system used along with scaling alters the surface roughness of orthodontic wire. How to cite this article Talic NF. Effect of Air-powder Polishing on the Surface Topography of Orthodontic Stainless Steel Wires. World J Dent 2017;8(4):262-266.

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Mihailescu, Dănuţ, Octavian Frincu, and Marius Corneliu Gheonea. "The Comparative Analysis of the Concentration of Microparticles during Mechanized MAG Welding Using Cored Wires." Advanced Materials Research 814 (September 2013): 76–81. http://dx.doi.org/10.4028/www.scientific.net/amr.814.76.

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Use of cored wire - shielding gas (gas mixture) pair, during mechanized MAG welding, causes the microparticles formation which is harmful for the welder’s health. The paper presents the experimental method for determining the concentration of the microparticles generated during MAG welding when rutile cored wires (standard and low fume emission) and metal powder cored wires (standard and low fume emission) are used. Carbon dioxide and the shielding gas mixture are investigated, too. Four types of cored wires were comparatively analysed, when three wire speed values were applied. The research of the microparticles concentration was conducted after each welding bead deposition, at the upper part of the welding enclosure, using MicroDust Pro particulate monitor. After each weld bead was deposited, the metal frame of the welding enclosure was removed, and, the fumes and gases, produced during the welding process, were eliminated through two fans, positioned inside and outside of the equipment. Using rutile cored wire with low fume emission, a decrease of microparticles concentration up to 30% is noticed in comparison with standard rutile cored wire. Using metal powders cored wire with low fume emission, the microparticles concentration is diminished with 12.5% comparing with standard metal powders cored wire.

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Student, Mykhajlo, Myroslav Golovchuk, Halyna Chumalo, Volodymyr Hvozdetskii, Sergiy Markovych, and Hanna Pohkmurska. "Influence of Diameter of Electrode Powder-like Wires is on Mechanical Descriptions of Elektrodugovikh Coverages." Central Ukrainian Scientific Bulletin. Technical Sciences, no. 3(34) (October 2020): 32–42. http://dx.doi.org/10.32515/2664-262x.2020.3(34).32-42.

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The influence of the diameter of the electrode flux-cored wires on the mechanical characteristics of the electric arc coatings is carried out in the work. Electric arc coatings were obtained on the original equipment, developed and manufactured at the Institute of Physics and Mechanics. GV Karpenko NAS of Ukraine. For spraying, model flux-cored wires of basic doping systems Fe – Cr – C and Fe – Cr – B with a diameter of 1.6 and 2.4 mm were used. The influence of the diameter of flux - cored wires on the structure, electric arc coatings from model flux - cored wires of different diameters is investigated. The dependence of porosity, microhardness, adhesion to the steel base, abrasive wear resistance of electric arc coatings sprayed from flux-cored wires with different amounts of charge on the thickness of the lamellae in the coating structure has been established. The influence of the thickness of the lamellae in the structure of coatings sprayed from flux-cored wires with different amounts of charge (depending on their diameter 1.6 and 2.4 mm) on their abrasive wear resistance was determined. It was found that the thickness of the lamellae in the coatings of all analyzed alloying systems increased with increasing volume of molten metal at the ends of flux-cored wires with the corresponding formation of droplets of larger diameter during its dispersion by air jet. shell charge and high arc current. It is shown that the amount of oxide phase in the structure of coatings doubles with increasing spray distance of flux-cored wires from 80 to 120 mm. More oxide phase (40… 100%) was found in coatings formed of flux-cored wires with a diameter of 2.4 mm with a higher filling factor of its shell charge compared to coatings formed of flux-cored wires with a diameter of 1.6 mm with lower filling. This is due to the larger volume of the charge in the powder wires of larger diameter, the cavities between the powders in which are filled with air, which intensively oxidizes the melt droplets inside the powder wires and at their ends during spraying. It is established that the porosity and microhardness of coatings from the developed flux-cored wires increase with the increase of the thickness of the lamellae in their structure and, accordingly, the diameter of the flux-cored wires. The increase in micro hardness is due to less evaporation and burnout of alloying elements from the droplets forming the coating, and the increase in porosity is caused by intensive spraying of droplets when hitting the sprayed surface, which contributes to micro cavities between the lamellae of the coating. It was found that with increasing the thickness of the lamellae in the structure of coatings of flux-cored wires 250H21VFGS and flux-cored wires 50HN2R5GS their adhesion to the steel base decreased slightly due to the occurrence of tensile stresses in coatings, which cause micro cracks or cracks. At the same time, the adhesion of 50X6MG2C flux-cored wire coatings to steel increased due to the higher carbon content of large lamellae and favorable conditions for the formation of high-carbon martensite, which has the lowest coefficient of thermal expansion and causes the lowest residual tensile stresses. It was found that the abrasive and gas-abrasive wear resistance of coatings from flux-cored wires 250Х21ВФГС decreased, and from flux-cored wires 50ХН2Р5ГС increased due to the increase in the thickness of the lamellae in their structure using a larger diameter.

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Kozyrev, N. A., R. E. Kryukov, V. M. Shurupov, N. V. Kibko, and L. P. Bashchenko. "TUNGSTEN RECOVERY FROM OXIDE DURING FLUX CORD WIRE SURFACING." Izvestiya. Ferrous Metallurgy 62, no. 3 (June 20, 2019): 215–21. http://dx.doi.org/10.17073/0368-0797-2019-3-215-221.

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Influence of introduction of tungsten powder and tungsten concentrate into surfacing flux-cored wire on structure, structural components microhardness, hardness and wear of the surfacing layer has been studied. Flux cored tungsten-containing wires of H- and E-types according to the IIW classification were manufactured for surfacing in laboratory. Powders of silicon KR-1 (GOST 2169 – 69), manganese MR-0 (GOST 6008 – 82), chromium PKhA-1M (industrial standard TU 14-1-1474 – 75), vanadium VEL-1 (industrial standard TU 48-0533 – 71), nickel PNK-1l5 (GOST 9722 – 97), aluminum PAP-1 (GOST 5494 – 95), tungsten PVT (industrial standard TU 48-19-72 – 92) and iron powder PZhV-1 (GOST 9849 – 86) were used as fillers. In some wires tungsten concentrate KSh-4 (GOST 213 – 83) produced by “AIR” mining company” JSC was used instead of tungsten powder. Gas cleaning dust of aluminum production of the following chemical composition: 21.00 – 43.27 % Al2O3; 18 – 27 % F; 8 – 13 % Na2O; 0.4 – 6.0 % K2O; 0.7 – 2.1 % CaO; 0.50 – 2.48 % SiO2; 2.1 – 2.3 % Fe2O3; 12.5 – 28.2 % Cgen; 0.03 – – 0.90 % MnO %; 0.04 – 0.90 % MgO; 0.09 – 0.46 % S; 0.10 – – 0.18 % P (by weight) was used as a carbon-containing reducing agent. Wire with diameter of 5mm manufactured at laboratory installation ASAW 1250 tractor was used for surfacing. Surfacing modes were: Is = 400 – 450 A; Ud = 32 ÷ 36 V; Vs = 24 ÷ 30 m/h. Surfacing was performed under a layer of AN-26S flux and flux made of silicomanganese slag; number of deposited layers – 5. Chemical composition of deposited metal was determined, metallographic analysis of deposited layer was carried out: size of the former austenite grain, size of martensite needles, degree of contamination by nonmetallic inclusions were stated and wear tests were carried out, hardness and microhardness were measured. The possibility in principal of using tungsten concentrate instead of tungsten powder in studied flux cored wires is shown, degree of tungsten extraction was calculated. For H-type fluxcored wire, introduction of tungsten concentrate instead of tungsten powder into the charge of wire does not increase contamination of deposited layers with nonmetallic inclusions and reduces size of the primary austenite grain. Use of tungsten concentrate in E-type flux-cored wire manufacturing helps to reduce size of the primary austenite grain and size of martensite needles, increasing microhardness of martensite in structure of deposited layer. Introduction of tungsten concentrate instead of tungsten powder into the composition of the charge of H-type wire provides a significant increase in hardness and wear resistance of deposited layer.

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Noonai, Nakhon, Anak Khantachawana, Pongpan Kaewtatip, and Julathep Kajornchaiyakul. "Improvement of Mechanical Properties and Transformation Behavior of NiTi Drawn Wires for Orthodontics Applications." Advanced Materials Research 378-379 (October 2011): 623–27. http://dx.doi.org/10.4028/www.scientific.net/amr.378-379.623.

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NiTi shape memory alloy is widely used in dental applications such as orthodontics arch wire, mini screw implant, orthodontics spring, etc., because of its favorable superelasticity and shape memory effect. Wire drawing is a fundamental manufacturing process used for producing orthodontics arch wires. It is well known that cold-work occurred during wire drawing operation is also important to control mechanical properties and transformation temperature of NiTi wires. Thus, the purpose of this work is to study the effect of cold working by means of reduction ratio of cross -sectional area and heat-treatment temperatures on transformation and mechanical behavior of the drawn wires for utilized as orthodontic wires. The wire material used in this study is Ni51.4Ti48.6 (at%) alloy with various initial diameters with targeted wire diameter of 0.51mm (0.02 inch). The die for wire drawing is made of tungsten carbide which is inserted into a steel case. The dies were designed to have different reduction ratio of cross sectional area for 4 levels; 10%, 20%, 30% and 40%, respectively. The lubricant used in this study is sodium stearate powder. In order to investigate the influences of heat-treatment temperatures, the drawn wires are heat-treated at 400 °C and 600 °C for 3.6ks. The results showed that percentages of reduction of cross sectional area and heat-treatment temperature strongly affect mechanical properties and transformation temperatures. Superelasticity was confirmed in an alloy heat-treated at 400 °C. The results obtained can be used to determine the optimum properties of NiTi wire in order to utilized as orthodontics arch wires.

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Mihailescu, Dănuţ, Octavian Frincu, and Marius Corneliu Gheonea. "The Comparative Analysis of Gas Emissions during Mechanized MAG Welding Using Cored Wires." Advanced Materials Research 814 (September 2013): 82–86. http://dx.doi.org/10.4028/www.scientific.net/amr.814.82.

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The use of cored wire - shielding gas (gas mixture) pair, during mechanized Metal Active Gas - MAG welding, leads to the formation of gas emissions (CO2, CO, NOx, NO, O3 etc) which is harmful for the welder’s health. The paper addresses the experimental method applied to establish the gas emissions developed during MAG welding when rutile cored wires (standard and low fume emissions) and metal powder cored wires (standard and low fume emissions) are used. Carbon dioxide and the shielding gas mixture are investigated, too. Four types of cored wires were comparatively analysed, when three wire speed values were applied. The experimental results have revealed that using rutilic cored wires and increasing the speed feed, an augmentation of CO (ppm), constant values of O2 (%), insignificant constant values of NO (ppm) and NOx (ppm) and absence of CO2 (%) are achieved. Using metal cored wires and increasing the speed feed, increase of CO (ppm), insignificant values of NO (ppm) and NOx (ppm), and constant values of CO2 (%) and O2 (%) are noticed.

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Li, Yong Peng, Hui Huang, and Xi Peng Xu. "Development Evaluation of Mechanical Properties of Brazed Diamond Wire." Solid State Phenomena 175 (June 2011): 294–99. http://dx.doi.org/10.4028/www.scientific.net/ssp.175.294.

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Fixed-abrasive wire saw, with its ability to cut hard brittle material, such as silicon ingots, crystals and quartz, has emerged as a leading technology for production in semiconductor and photovoltaic industry. There are some defects in conventional fixed-abrasive wire saw such as significant low holding abrasive ability, low machining efficiency, high running costs, etc. A new fixed-abrasive wire, namely brazed diamond wires have been developed to overcome these problems. In this paper, brazed diamond wire were carried out to braze two different size diamond grits onto two different thin steel wires by using a nickel-based powder as brazing alloy. The mechanical properties of brazed diamond wire were evaluated by tensile and breaking twist experiment. The experimental results showed that the heating in the brazing process has litter influence on the wire mechanical properties. The addition of brazed alloy and diamond grits sharply decreased the wire mechanical properties significantly, both in the tensile strength and breaking twist angle. Bigger diamond grit would make the accumulation of brazed alloy which leaded to the deterioration of diameter consistency of wires.

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BALAMURUGAN, S., K. HIGASHIKAWA, T. NAKAMURA, and K. OSAMURA. "ANNEALING EFFECTS IN PIT-PROCESSED MgB2/SUS316 (STAINLESS STEEL) COMPOSITE WIRES." Modern Physics Letters B 19, no. 16 (July 20, 2005): 793–800. http://dx.doi.org/10.1142/s0217984905008803.

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The MgB 2/ SUS316 (stainless steel) wires were fabricated by powder-in-tube (PIT) method using commercially available superconducting MgB 2 powder at ambient pressure, and the annealing effects on Tc as well as Jc were investigated. The as-rolled MgB 2/ SUS316 wire showed a zero-resistance superconducting transition temperature (Tc) at 33.4 K and a critical current density [Formula: see text] of 2.22 kAcm-2 at 18.4 K. In order to check the annealing effect, the different pieces of the as-rolled wires were annealed at various annealing conditions under Ar atmosphere in vacuum (60 cm Hg) sealed silica-tube. As compared to the MgB 2/ Fe wires, the annealing temperature and duration were lower and much shorter respectively, for the MgB 2/ SUS316 (stainless steel) wires. On annealing at 873 K for ~ 1 s, we obtained the best sample with a [Formula: see text] of 12.1 kAcm-2 at 16.9 K with a maximum Tc of 36.1 K. Longer annealing time (~ 10 s) above 873 K reduced the Tc as well as the Jc, indicating a possible chemical reaction between the MgB 2 cores and the sheath material.

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Stepanova, Kseniya, Petr Petrov, and Anatoliy Platonov. "Inner stress analysis through methods of X-ray diffractometry in deposited metal and in periweld area by alloy rare-earth elements." Science intensive technologies in mechanical engineering, no. 4 (April 21, 2020): 3–8. http://dx.doi.org/10.30987/2223-4608-2020-4-3-8.

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Through the methods of X-ray diffractometry there are defined values of residual stresses in a weld metal and a periweld area obtained by hand arc welding deposition with experimental powder wires with the different rare-earth element composition of the Tomtorsky deposit (Yakutia, Russia). It is revealed that in the deposited metal and in the periweld area (PWA) with REM there are formed tensile inner stresses. In weld metal and in the PWA deposited with wire containing 0.7% of REMs there are revealed tensile inner residual stresses which cam serve as an additional mechanism restraining a formation stage and delaying a process of post-welding cracks propagation. An optimum composition of powder wires with the modifying REM admixture is offered.

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Lv, Fuzai, Pengfei Zhang, Zhifeng Tang, Yonggang Yue, and Keji Yang. "A Guided Wave Transducer with Sprayed Magnetostrictive Powder Coating for Monitoring of Aluminum Conductor Steel-Reinforced Cables." Sensors 19, no. 7 (March 30, 2019): 1550. http://dx.doi.org/10.3390/s19071550.

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Aluminum conductor steel-reinforced (ACSR) cables are typically used in overhead transmission lines, requiring stringent non-destructive testing owing to the severe conditions they face. Ultrasonic guided wave inspection provides promising online monitoring of the wire breakage of cables with the advantages of high sensitivity, long-range inspection, and full cross-sectional coverage. It is a very popular method to generate and receive guided waves using magnetostrictive and piezoelectric transducers. However, uniformly coupling the acoustic energy excited by transducers into multi-wire structures is always a challenge in the field application of guided waves. Long-term field application of piezoelectric transducers is limited due to the small coupling surface area, localized excitation, and couplant required. Conventional magnetostrictive transducers for steel strand inspection are based on the magnetostrictive effect of the material itself. Two factors affect the transducing performance of the transducers on ACSR cables. On one hand, there is a non-magnetostrictive effect in aluminum wires. On the other hand, the magnetostriction of the innermost steel wires is too weak to generate guided waves. The bias magnetic field is attenuated by the outer layers of aluminum wires. In this paper, an alternative sprayed magnetostrictive powder coating (SMPC) transducer was developed for guided wave generation and detection in ACSR cables. The Fe83Ga17 alloy powder with large magnetostriction was sprayed uniformly on the surfaces of certain sections of the outermost aluminum wires where the transducer would be installed. Experimental investigations were carried out to generate and receive the most commonly used L(0,1) guided waves for wire breakage detection at frequencies of 50 and 100 kHz. The results demonstrate that the discernable reflected waves of the cable end and an artificial defect of three-wire breakage (5.5% reduction in the cable’s cross-sectional area) were received by the transducer with SMPC, which was impossible for the transducer without SMPC. This method makes long-term and online monitoring of ACSR cables feasible due to the high coupling efficiency and good structural surface adaptability.

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Lerner, Marat, Alexandr Pervikov, Elena Glazkova, Nikolay Rodkevich, and Nikita Toropkov. "Electrical Explosion Synthesis, Oxidation and Sintering Behavior of Ti-Al Intermetallide Powders." Metals 11, no. 5 (May 5, 2021): 760. http://dx.doi.org/10.3390/met11050760.

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In this research, Ti-Al powders were produced by electrical explosion of twisted titanium and aluminum wires. The resulting powders were pressed and sintered in a vacuum to obtain bulk composites. Transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), scanning electron microscopy (SEM), and X-ray diffraction (XRD) studies were performed to analyze synthesized powders and bulk composites. The studies carried out showed the presence of α-Ti, α2-Ti3Al, and γ-TiAl phases, which are formed by coalescence of Ti and Al clusters formed in the process of non-synchronous electrical explosion of twisted wires. Furthermore, an increase in the energy injected into the wires leads to a decrease in the content of micron particles in the powder. During sintering of pressed Ti-Al powder in the range 800–1250 °C, phase transformations occur due to the diffusion of aluminum atoms towards Ti compounds. The research findings can be used to obtain Ti-Al particles and bulk composites with a controllable phase composition.

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KOISHI, TETSUYA, SATORU ISHIHARA, TSUNEO SUZUKI, TADACHIKA NAKAYAMA, HISAYUKI SUEMATSU, and KOICHI NIIHARA. "SYNTHESIS OF NiAl INTERMETALLIC COMPOUND NANOSIZED POWDERS BY PULSED WIRE DISCHARGE." Functional Materials Letters 05, no. 02 (June 2012): 1260014. http://dx.doi.org/10.1142/s1793604712600144.

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NiAl nanosized powders were synthesized by pulsed wire discharge (PWD) using twisted Ni and Al wires with various number of turns (Nt). The X-ray diffraction (XRD) patterns indicated that the optimum conditions for synthesized NiAl nanosized powders were usage of a twisted Ni and Al wire with 0.4 turn/mm discharged in N2 gas. For clarifying the dependence of Nt on the powder purity, waveforms of current, voltage and deposited energy during the discharges were measured. From the waveforms, deposited energy ratio until a voltage peak (Kp), which is an index to evaluate volume fraction of evaporated wire, was calculated. In low Kp conditions, nanoparticles with low composition ratio of Ni (C Ni ) and large particles with high C Ni were frequently observed. This result indicated that the Ni wire had a high boiling point than that of Al so that unevaporated Ni remained as large liquid droplets in the discharge. Decrease of Kp was thought that the increase of Nt introduced lattice defects by plastic deformation to increase the resistance and to evaporate the wire partially. From the results above, a method to synthesize NiAl intermetallic compound nanosized powders by PWD was successfully developed using Ni and Al twisted wires. In addition, Kp turned out to be important in synthesizing single-phase nanosized powders.

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Osetkovskiy, I. V., N. A. Kozyrev, A. I. Gusev, O. A. Kozyreva, R. A. Gizatulin, and A. V. Valueva. "Influence of the Cobalt Additive on the Flux Cored Wire of System Fe-C-Si-Mn-Cr-Ni-Mo-V." Key Engineering Materials 736 (June 2017): 63–67. http://dx.doi.org/10.4028/www.scientific.net/kem.736.63.

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Studied the effect of the introduction of cobalt into the charge powder fused wire system Fe-C-Si-Mn-Cr-Ni-Mo-V, used in cladding assemblies and equipment parts and mechanisms operating under abrasive and abrasive shock loads., the samples cored wires were manufactured in the laboratory conditions using appropriate powder materials and as a carbonfluoride contained material were used the dust from gas purification of aluminum production.

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Chen, Shu-Fan, Hiroyuki Komeda, Koji Fujii, Koji Tanoue, and Hidehiko Matsuda. "Recrystallization Process of Powder Metallurgy Tungsten Wires." Journal of the Japan Institute of Metals 53, no. 12 (1989): 1198–207. http://dx.doi.org/10.2320/jinstmet1952.53.12_1198.

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Qi, Yanpeng, Xianping Zhang, Zhaoshun Gao, Zhiyu Zhang, Lei Wang, Dongliang Wang, and Yanwei Ma. "Superconductivity of powder-in-tube Sr0.6K0.4Fe2As2 wires." Physica C: Superconductivity 469, no. 13 (July 2009): 717–20. http://dx.doi.org/10.1016/j.physc.2009.03.008.

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Dubots, P., and J. Cave. "Critical currents of powder-based superconducting wires." Cryogenics 28, no. 10 (October 1988): 661–67. http://dx.doi.org/10.1016/0011-2275(88)90149-x.

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Frye, Clint D., J. H. Edgar, Yi Zhang, Kevin Cooper, Luke O. Nyakiti, and D. K. Gaskill. "Synthesis of Icosahedral Boron Arsenide Nanowires for Betavoltaic Applications." MRS Proceedings 1439 (2012): 69–75. http://dx.doi.org/10.1557/opl.2012.1156.

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ABSTRACTWith a wide band gap of greater than 3.0 eV and the ability to self-heal from radiation damage, icosahedral boron arsenide (B12As2) is an apt candidate for use in next-generation betavoltaics. By capturing and converting high energy electrons from radioisotopes into usable electricity, “nuclear batteries” made from B12As2 could potentially power devices for decades. Compared to bulk crystals or epitaxial films, B12As2 nanowires may have lower defect densities or may even be defect-free, leading to better electrical properties and device performance. In our study, B12As2 nanowires were synthesized via vapor-liquid-solid (VLS) growth using platinum powder and nickel powder on silicon carbide and 20 nm thick nickel film on silicon substrates from 700 °C to 1200 °C. Platinum yielded the highest quality nanowires from 900 °C to 950 °C, resulting in platinum particles densely covered with wires formed by straight segments connected by sharp angular kinks. At these growth temperatures, diameters ranged from less than 30 nm to about 300 nm as determined by scanning electron microscopy and transmission electron microscopy. Growth temperatures of 850 °C or less produced curled wires 200-1000 nm in diameter. Transmission electron microscopy and selected area electron diffraction revealed excellent crystallinity in wires grown above 850 °C, while wires grown at or below 850 °C were partially amorphous. Wires grown from the 20 nm nickel film displayed similar morphologies at temperatures up to 850 °C; from 900 °C to 950 °C, straight, isolated wires were grown with diameters of 200-400 nm. Nickel powder only produced wires larger than 1 μm in diameter. The comparative quality and growth of B12As2nanowires will be discussed.

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Pervikov, Alexander, Nikita Toropkov, Sergey Kazantsev, Olga V. Bakina, Elena Glazkova, and Marat Lerner. "Preparation of Nano/Micro Bimodal Aluminum Powder by Electrical Explosion of Wires." Materials 14, no. 21 (November 2, 2021): 6602. http://dx.doi.org/10.3390/ma14216602.

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Electrical explosion of aluminum wires has been shown to be a versatile method for the preparation of bimodal nano/micro powders. The energy input into the wire has been found to determine the relative content of fine and coarse particles in bimodal aluminum powders. The use of aluminum bimodal powders has been shown to be promising for the development of high flowability feedstocks for metal injection molding and material extrusion additive manufacturing.

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Vinod, Krishnankutty, and Syamaprasad Upendran. "Studies on Development of MgB₂ Superconductor with Improved In-Field Critical Current Density." Advanced Materials Research 117 (June 2010): 63–68. http://dx.doi.org/10.4028/www.scientific.net/amr.117.63.

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The present study focuses on the preparation of good quality MgB2 superconductor in bulk, wire/tape forms and on the improvement of in-field critical current density [JC(H)]. MgB2 bulk superconductor was prepared by a simple Powder-In-Sealed-Tube (PIST) method and MgB2 wires and tapes were prepared by the Powder-In-Tube (PIT) method. A novel electrical self-heating method was introduced for the preparation of Fe sheathed MgB2 wires and tapes. Burned Rice Husk (BRH), an inexpensive natural material is found to be one of the best additives for enhancing the in-field critical current density of MgB2. By selecting suitable combinations of additives a significant enhancement of the critical current density by 1-2 orders of magnitude were achieved for fields > 5 T, at 5-15 K.

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Gusev, A. I., N. A. Kozyrev, I. V. Osetkovskiy, O. A. Kozyreva, and D. V. Valuev. "Quality of Metal Deposited Flux Cored Wire with the System Fe-C-Si-Mn-Cr-Mo-Ni-V-Co." Key Engineering Materials 736 (June 2017): 23–28. http://dx.doi.org/10.4028/www.scientific.net/kem.736.23.

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Studied the effect of the introduction of vanadium and cobalt into the charge powder fused wire system Fe-C-Si-Mn-Cr-Ni-Mo-V, used in cladding assemblies and equipment parts and mechanisms operating under abrasive and abrasive shock loads. the cored wires samples were manufactured in the laboratory conditions and using appropriate powder materials and as a carbonfluoride contained material were used the dust from gas purification of aluminum production.

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Ma, Qiong, and Dong Xie. "Base on Double Thermocouple the Casting Powder Crystallization Measurement." Advanced Materials Research 889-890 (February 2014): 695–98. http://dx.doi.org/10.4028/www.scientific.net/amr.889-890.695.

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This paper proposed the measuring device for the casting powder crystallization and the crystalline proportion test by the double thermocouple. The two different dual platinum-rhodium thermocouple wires are acted as heating element and temperature measurer at the same time, so that, the temperature of both wires apart can be controlled accurately. Adjusting the two wires distance discretionarily, the crystalline state can be observed under the different range of temperature of flux film on the both sides. The fast temperature raising and high efficiency of metering technology is designed for the measurement device and achieved great sense to research the casting powder characters in the crystallizer.

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Mao, Z., X. Zou, X. Wang, X. Liu, and W. Jiang. "Circuit simulation of the behavior of exploding wires for nano-powder production." Laser and Particle Beams 27, no. 1 (January 8, 2009): 49–55. http://dx.doi.org/10.1017/s026303460900007x.

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AbstractThe electrical behavior of exploding wires was obtained by numerically solving the nonlinear differential equation describing the discharge circuit. For metal wires of high conductivity and low sublimation heat, such as copper, aluminum, gold, and silver, the circuit simulation can be well performed based on the resistivity model developed by Tucker in which the resisitivity is expressed by the explicit functions of specific action, i.e., ρ = f(g). For metals such as titanium and zinc with anomalously changing resistivity, i.e., decreasing rather than increasing with the liquid heating, the circuit simulation of the exploding wires can be performed using the implicit relationship between ρ andgthat is read out point by point from the experimentally measured curve. Using the circuit simulation, the rate of the energy deposition in the exploding wires before the explosion can be obtained, which is helpful to choose the right experimental conditions for possible overheating that is desirable for getting smaller nano-powders produced by exploding wires.

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Wu, Y. F., G. Yan, J. S. Li, Y. Feng, Shao Kai Chen, Hui Ping Tang, H. L. Xu, Cheng Shan Li, Ping Xiang Zhang, and Ya Feng Lu. "Influence of Preparation Process on Microstructure, Critical Current Density and T_c of MgB₂/Fe/Cu Wires." Materials Science Forum 546-549 (May 2007): 2031–34. http://dx.doi.org/10.4028/www.scientific.net/msf.546-549.2031.

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The powder-in-tube MgB2 wires were prepared by high energy milling of Mg and B powder. The powder was not mechanically alloyed for 2h short milling time. However, the MgB2 grains in wires were very small (20~100nm) and resemble the dimple after post-heat treatment. The clear evidence for transcrystlline fracture was observed. It indicated that the grain connection was greatly improved and the fluxing pinning was significantly enhanced. Another point to view was no intermediate annealing during the whole rolling process. The influence of the post-heat treatment on the transport current density was studied. Despite the lower Tc of about 35K, the transport current density reached to 3×104A/cm2 at 15K and 3.5T for wires sintered at 700°C.

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24

Mao Zhiguo, 毛志国, 邹晓兵 Zou Xiaobing, 王新新 Wang Xinxin, and 江伟华 Jiang Weihua. "Nano-powder production by electrical explosion of wires." High Power Laser and Particle Beams 22, no. 3 (2010): 691–95. http://dx.doi.org/10.3788/hplpb20102203.0691.

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25

Murzaev, V. P., D. B. Slinko, and Yu N. Shchetinin. "Powder wires for resource-saving electric arc spraying." Sel'skohozjajstvennaja tehnika: obsluzhivanie i remont (Agricultural Machinery: Service and Repair), no. 1 (January 1, 2021): 11–17. http://dx.doi.org/10.33920/sel-10-2101-02.

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One of the promising methods of thermal spraying is the arc spraying. The use of electric arc spraying is particularly eff ective for the protection of metal structures from corrosion, receiving heat resistant, heat-resistant and wear-resistant coatings. This method is also eff ective in the recovery and hardening de tackles tractors, trucks and agricultural machinery. Signifi cantly extend the scope of the arc deposition can be using the new electrode materials in the form of fl ux-cored wires, the cost of which can be reduced by using materials for dying as a band , with factories producing cable products and iron shavings tion of machine-building enterprises.

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26

Chan, Tien Yin, De Xing Wang, Hua Jun Chang, and Chia Liang Chen. "Fabrication of Gas-Permeable Die Materials Having Orthogonally Arrayed Pore Channels." Materials Science Forum 534-536 (January 2007): 961–64. http://dx.doi.org/10.4028/www.scientific.net/msf.534-536.961.

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Defects of components as a result of entrapped gases during an injection process could be minimized with the utilization of a gas-permeable metal die material in the mold, due to its excellent permeability of air. Conventional gas-permeable die materials employ low temperature sintering of loosely packed steel powders with or without the addition of pore-forming polymers, whose microstructures are usually weak and their gas permeability values are also low. In this study, gas-permeable metal die materials are developed using tool steel powder, packed in a mold having the insertion of orthogonally arrayed polymer wires. Linear gas-permeable channels in orthogonal array are thus developed by the burning out of the polymer wires, which yield a large value of air permeability. The value of air permeability can be adjusted by changing the diameter and number density of the polymer wires. The tool steel powder can be made fully dense by supersolidus liquid phase sintering, yielding a microstructure with a wear resistance value much larger than that of the conventional gas-permeable die material.

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27

Mihăilescu, Dănuţ, Marius Cornel Gheonea, and Bogdan Georgescu. "Determining the Coefficients of Fusion and of Weld Deposition at Mechanized Mag-C Welding with Solid Wire and Cored Wires." Applied Mechanics and Materials 657 (October 2014): 301–5. http://dx.doi.org/10.4028/www.scientific.net/amm.657.301.

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In the case of the MAG welding of carbon and low-alloyed steels wires or hollow wires with (rutilic or basic) flux with metallic powder or self-protection are used. In indoors weldings huge quantities of smoke, gases, dust and particles in suspension, etc. get accumulated. These noxious substances produced during the welding process may severely affect the welders health. To improve the welders working conditions, on an international scale, the following are used: welding masks with self-obscurazation and air control; noxious substances vacuum cleaners fitted with filters; MAG welding pistols with gase and smoke absorbing devices. For the improvement of the welders working conditions, producers of welding materials invented hollow wires with (rutilic flux or with metallic powder) with a smoke-reduced emission [1,2,3,4,5].

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28

Borisov, Yu S., A. L. Borisova, N. V. Vihilyanska, I. A. Demyanov, and O. M. Burlachenko. "Electric arc spraying of intermetalic Fe–Al coatings using different solid and powder wires." Paton Welding Journal 2021, no. 3 (March 28, 2021): 16–21. http://dx.doi.org/10.37434/tpwj2021.03.03.

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29

Ibrahim, Sarmad A., Sadeq H. Lafta, and Wafaa A. Hussain. "Impact strength of surface treated SS316L wires reinforced PMMA^**." Journal of the Mechanical Behavior of Materials 30, no. 1 (January 1, 2021): 272–78. http://dx.doi.org/10.1515/jmbm-2021-0029.

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Abstract Stainless steel 316L (SS316L) as a significant bio-material, their wires were used to support the PMMA matrix. Two simple and low-cost surface pretreatments for SS316L wires were performed to enhance denture impact strength: mechanical scratching (treating SS316L wires with SiC powder inside a rotating container) and electrochemical anodizing. Three mechanical scratching samples for different periods of 60, 90 and 120min were prepared. Anodizing technique conditions were: Ethylene glycol with perchloric acid as an anodizing solution, 15V supplying and graphite rod as an anode. Anodizing process involved three pretreating periods of 15, 20, and 30min. All the prepared samples had dimensions of 65 × 10 × 3 mm. SEM technique showed different morphology nature involved holes, scratches and pores with a density of 104/μm2 and a crack length of 60μm. The PMMA reinforced with scratched stainless steel 316L wire surface for 120 min presented the highest impact strength value (42 kJ/m2) with (450.91%) increment. Anodizing samples showed a fluctuating behavior of samples with enhancing in the impact strength of anodizing wire for 20min of about 26.99 kJ/m2, which is still lower than that for scratched samples in average.

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30

Bischof, M., H. Leitner, H. Clemens, P. Staron, G. Dehm, A. Voiticek, and W. Knabl. "Microstructure and mechanical properties of Si and YN doped powder metallurgical tantalum." International Journal of Materials Research 95, no. 7 (July 1, 2004): 573–78. http://dx.doi.org/10.1515/ijmr-2004-0111.

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Abstract Tantalum has a wide range of applications due to its high melting temperature, its corrosion resistance and its mechanical and electrical properties. One of these applications are fine wires which are needed for Ta-capacitors. During fabrication of such components, the wires are exposed to high temperatures and, thus, grain growth combined with embrittlement becomes a major problem. In the present work, the effects of doping with small amounts of Si and YN on microstructure and mechanical properties of annealed Ta-wires have been investigated. Doped samples show a higher hardness and strength than samples of pure powder metallurgical (PM) Ta; however, the grain growth kinetics are very similar. Samples doped with Si and samples doped with both Si and YN exhibit almost identical properties.

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31

Lerner, Marat, Alexander Pervikov, Elena Glazkova, Nikolay Rodkevich, Konstantin Suliz, Sergey Kazantsev, Nikita Toropkov, and Olga Bakina. "Synthesis of Ti–Al Bimodal Powder for High Flowability Feedstock by Electrical Explosion of Wires." Metals 12, no. 3 (March 11, 2022): 478. http://dx.doi.org/10.3390/met12030478.

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In this research, Ti–Al bimodal powders were produced by simultaneous electrical explosion of titanium and aluminum wires. The resulting powders were used to prepare powder–polymer feedstocks. Material characterization involving X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and melt flow index (MFI) determination were carried out to characterize bimodal powders obtained and evaluate the influence of the powder composition on the feedstock flowability. The bimodal distribution of particles in powders has been found to be achieved at a current density of 1.2 × 107 A/cm2 (the rate of energy input is 56.5 J/μs). An increase in the current density to 1.6 × 107 A/cm2 leads to a decrease in the content of micron particles and turning into a monomodal particle size distribution. The use of bimodal powders for powder–polymer feedstocks allows to achieve higher MFI values compared with monomodal powders. In addition, the use of electroexplosive synthesis of bimodal powders makes it possible to achieve a homogeneous distribution of micro- and nanoparticles in the feedstock.

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32

Kozyrev, N. A., A. A. Usol’tsev, R. E. Kryukov, A. I. Gusev, and I. V. Osetkovskii. "Operation indices of the new cored wire of Fe−C−Si−Мn−Сr−Ni−Mo system." Ferrous Metallurgy. Bulletin of Scientific , Technical and Economic Information 75, no. 7 (August 8, 2019): 860–68. http://dx.doi.org/10.32339/0135-5910-2019-7-860-868.

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To protect and repair details of equipment, subjected to abrasive and shock-and-abrasive wear, a build-up of hard alloy is widely used to increase the wear resistance of details, operating under abrasion conditions. Cored wires of Fe−C−Si−Мn−Сr−Ni−Mo system of type A and B by MIS classification are the main wires used for wear-resistant build-up in Russia. For effective application of building-up wires it is necessary to know the dependence of built-up layer hardness and its wear resistance on mass share of elements included into the composition of the cored wires systems. Influence of chemical composition of he built-up layer, obtained by the building-up with application of new powder systems of Fe−C−Si−Мn−Сr−Ni−Mo, protected by RF patents, on its physical and mechanical properties studied. Based on the results of the multifactor correlation analysis accomplished, dependences of the built-up layer hardness and its wear resistance on mass share of elements included into the composition of the cored wires of Fe−C−Si−Мn−Сr−Ni−Mo system determined. The dependences obtained were used for forecasting of the built-up layer hardness and its wear resistance at changes of the chemical composition of the built-up layer. The tests of JOY 4LS20 mining machine screw protective plates at Kemerovo region mines, built-up by the elaborated cored wire, showed an increase of the resistance by 19.3% comparing with the analog plates built-up by DRATEC wire.

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33

Student, Mykhajlo, Myroslav Golovchuk, Volodymyr Hvozdetskii, Halyna Veselivska, Sergiy Markovych, and Rostyslav Yatsyuk. "Influence of Composition of Charge Materials of Flux-cored Wires on Mechanical Characteristics and Corrosion Resistance of Electric Arc Coatings." National Interagency Scientific and Technical Collection of Works. Design, Production and Exploitation of Agricultural Machines, no. 50 (2020): 188–95. http://dx.doi.org/10.32515/2414-3820.2020.50.188-195.

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The influence of charge materials of flux-cored wires on their mechanical characteristics, chemical microheterogeneity and corrosion resistance in an aqueous solution of 3% NaCl was established. It is shown that, in contrast to coatings made of solid wires, coatings sprayed using flux-cored wires (PO) have a high chemical heterogeneity. This is due to the fact that the droplets that disperse from the PD melt and form a coating have different chemical compositions. This is caused by incomplete fusion of the charge and steel shell at the ends of the PD during electric arc spraying of coatings. To reduce the chemical micro-heterogeneity, it is proposed to add powders of ferroalloys FeSi, FeMn and self-flux PG-10H-01 to the charge of powder wire containing chromium, boron, carbon-containing components (Cr, FH, PG-100, B4C, FCB) between the components of the charge, homogenize the melt of PD and, as a consequence, reduce the microheterogeneity of the coatings. The presence of chromium, ferrochrome, ferro-silicon and ferromanganese in the charge of PD 90Х17РГС and PD 75Х19Р3ГС2 determines the minimum chemical microheterogeneity of coatings from these wires and, as a result, ensures their high corrosion resistance, which is close to corrosion steel18. To increase the completeness of fusion of the components of the PD charge between itself and its steel shell, it is proposed to add to the PD charge powders of ferroalloys Fe-Mn, Fe-Si, which have a low melting point, able to interact with refractory components of the charge to form low-temperature eutectics. The addition of ferro-silicon, ferromanganese and self-flux alloy PN-10H-01 powders based on ferrochrobor and ferrochrome provided high hardness of electric arc coatings, low heterogeneity in terms of chromium content in coating lamellae and, as a consequence, high corrosion resistance.

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34

Jiang, Xiangcao, Jiupeng Song, Fusheng Peng, Donghong Guo, Yijin Fang, Shaowei Dai, and Bingcan Zhu. "Microstructure and High-Temperature Performance of High K-Doped Tungsten Fibers Used as Reinforcement of Tungsten Matrix." Crystals 12, no. 1 (January 4, 2022): 63. http://dx.doi.org/10.3390/cryst12010063.

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Tungsten (W) fiber-reinforced tungsten (Wf/W) composite with ultra-high strength and high-temperature resistance is considered an attractive candidate material for plasma-facing materials (PFM) in future fusion reactors. The main component of Wf/W composite is tungsten wire, which is obtained through powder metallurgy and the drawing process. In this paper, high potassium (K)-doped tungsten wires with 98 ppm of K and 61 ppm of impurities are prepared using traditional and optimized processing technologies, respectively, and a comparative study with conventional K-doped tungsten wires with 83 ppm of K and 80 ppm of impurities is conducted. The high-temperature mechanical properties as well as the microstructure’s evolution of the prepared tungsten wires are investigated. The results show that the high-temperature performance of K-doped tungsten wires is improved by increasing the K content and by simultaneously reducing the impurities. By adopting small compression deformation and low-temperature processing technology, the high-temperature performance of high K-doped tungsten wires can be further improved. A microstructure analysis indicates that the excellent high-temperature performance is attributed to a combination of the small K bubble size, high K bubble number density, and long K bubble string, which are produced through optimization of the processing technology. A study on the processing technology and the performance of tungsten wires with a high K content and a high purity can provide important information regarding Wf/W composites.

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Serquis, A., L. Civale, D. L. Hammon, X. Z. Liao, J. Y. Coulter, Y. T. Zhu, M. Jaime, et al. "Hot isostatic pressing of powder in tube MgB2 wires." Applied Physics Letters 82, no. 17 (April 28, 2003): 2847–49. http://dx.doi.org/10.1063/1.1571231.

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36

Chevrel, Roger, Maryvonne Hirrien, Marcel Sergent, Michel Couach, Patrick Dubots, and Pierre Genevey. "Cold-powder metallurgy-processed chevrel-phase superconducting wires. II. Reacted “in situ” PbMo6S8 powder." Materials Letters 7, no. 12 (March 1989): 425–27. http://dx.doi.org/10.1016/0167-577x(89)90044-x.

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Zhang, Guo Qing, Hui Huang, and Xi Peng Xu. "An Experimental Study on Brazing of Diamonds onto Thin Steel Wires." Key Engineering Materials 443 (June 2010): 537–42. http://dx.doi.org/10.4028/www.scientific.net/kem.443.537.

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An experimental investigation was carried out to braze diamond abrasives onto thin steel wires, in which case the brazing was conducted in the vacuum and under high temperatures by using a nickel-based powder as brazing alloy. The morphologies and microstructures of the brazed wires were observed and the comprehensive mechanical properties of the brazed wires were tested. The brazed wires were also used to cut such brittle materials as ceramics, glass, and natural stone. It is shown that a typical phenomenon of brazing alloy’s climbing around the diamond grains was observed in brazing the wires. Through observing the cross-section of brazed wires, it is observed that there is a good bonding between the brazing alloy and the body of steel wires. The crystal grains of the steel wires grew significantly after brazing. Through observing the morphologies of the diamond wires and the surfaces of four workpiece materials, few diamond pull-outs were found on the wires and the kerfs on the workpiece materials were basically flat.

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38

Sobrero, C. E., M. T. Malachevsky, and A. Serquis. "Core Microstructure and Strain State Analysis in MgB2Wires with Different Metal Sheaths." Advances in Condensed Matter Physics 2015 (2015): 1–6. http://dx.doi.org/10.1155/2015/297363.

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We present a detailed analysis of the effect of the sheath materials on the microstructure and superconducting properties of MgB2wires produced by the powder-in-tube method (PIT). We reduced commercial MgB2powder by attrition milling in nitrogen atmosphere using tungsten carbide balls and obtained powders with grain sizes lower than 150 nm and different strain states through this process. Several Ti, stainless steel, and copper monofilamentary wires were prepared using these powders by the PIT method. We investigated different thermal treatments and mechanical paths during the processing of the wires for the enhancement of the critical currents. The superconducting properties were determined by magnetization measurements in a SQUID magnetometer. The correlation between the thermal treatments, structure, and superconducting properties is discussed.

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Osetkovskiy, I. V., N. A. Kozyrev, and R. E. Kryukov. "Abrasive Wear Resistance Comparative Analysis of the Metal Surfaced by Flux Cored Wires Systems Fe-C-Si-Mn-Ni-Mo-W-V and Fe-C-Si-Mn-Cr-Ni-Mo-V." Materials Science Forum 906 (September 2017): 1–7. http://dx.doi.org/10.4028/www.scientific.net/msf.906.1.

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In the article is shown the comparative analysis between structures of surfaced by the flux coded wire metal systems Fe-C-Si-Mn-Cr-Ni-Mo-V and Fe-C-Si-Mn-Ni-Mo-W-V. These powder wires are supposed to be used in recovering details and equipment components and machines, that works in conditions of intensive abrasive – shock wear. Manufacturing and surfacing of flux cored wires samples were made in laboratory conditions. Defined chemical composition of the surfaced metal. Deposited metal samples hardness and wear resistance were researched. In the course of deposited meta surface metallographic analysis were made following metallographic researches: defined nature and level of nonmetallic oxides impurity, type and morphology of the microstructure, grain size of surfaced samples. Estimation of the chemical composition components influence on the hardness and wear resistance were obtained.

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40

Coetsee, Theresa, and Frederik De Bruin. "Reactions at the molten flux-weld pool interface in submerged arc welding." High Temperature Materials and Processes 40, no. 1 (January 1, 2021): 421–27. http://dx.doi.org/10.1515/htmp-2021-0051.

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Abstract In submerged arc welding (SAW) of chromium (Cr) containing steels, Cr is usually added to the weld metal from the weld wire, and not from the welding flux. Manufacturing of weld wires of specific compositions is expensive and time consuming and cannot closely match all the desired alloy compositions. Therefore, the weld wire chemistry is usually over matched to the base plate composition. Better matching between the weld metal and base plate is possible if the weld metal incorporates Cr from Cr containing metal powder, instead of sourcing Cr from weld wire of limited Cr content. Because Cr is easily oxidised, the oxygen partial pressure in SAW must be controlled. This work illustrates the control of the oxygen potential at the molten flux-weld pool interface by using aluminium (Al) powder addition. The controlled oxygen potential at the molten flux-weld pool interface ensures increased Cr powder transfer into the weld pool, without interfering with oxygen transfer from the plasma arc to the weld pool. The objective of this work is to use targeted powder additions to better control Cr reactions in SAW to improve Cr metal transfer to the weld metal and maintain an acceptable level of oxygen in the weld metal.

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Pandheeradi, M., S. P. Vaze, D. W. Yuan, and H. A. Kuhn. "Modeling and Experimental Validation of Superconductor Tape Rolling." Journal of Manufacturing Science and Engineering 123, no. 4 (August 1, 2000): 665–73. http://dx.doi.org/10.1115/1.1371929.

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Efficient, defect-free manufacturing of high-temperature superconducting (HTS) wires and tapes is critical to a variety of defense and electrical power applications. To contribute to the improvement of these manufacturing operations, an analytical and experimental study of the early stages of the multipass rolling process for transforming HTS wires into tapes was conducted. The rolling process was simulated by a three-dimensional (3D) finite element model that uses the Drucker-Prager Cap plasticity model to represent the powder core and a Von-Mises plasticity model with isotropic hardening to represent the silver sheath. The predicted cross-sectional geometry of the tapes is compared with experiments. The results show that the tape cross-sectional geometry and powder core sizes can be predicted accurately. Further, alternate boundary conditions were found to have minimal effect on the predicted cross-sectional geometry for the range of reductions considered, even though the frictional shear stress distributions were significantly different.

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42

Bozheyev, Farabi, Vladimir V. An, and Yuriy Irtegov. "Properties of Copper and Molybdenum Sulfide Powders Produced by Self-Propagating High-Temperature Synthesis." Advanced Materials Research 872 (December 2013): 191–96. http://dx.doi.org/10.4028/www.scientific.net/amr.872.191.

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Copper and molybdenum sulfide nanopowders were prepared by self-propagating high-temperature synthesis in argon. The initial copper powder and molybdenum powder were produced by electric spark dispersion in hexane and by electrical explosion of wires (EEW) in argon, respectively. The powders were studied by electron microscopy, X-ray diffraction and Raman spectroscopy. The copper sulfide main phase is hexagonal 2H-CuS, whereas hexagonal 2H-MoS2 and rhombohedral 3R-MoS2 are characteristic for molybdenum disulfide. The lattice parameters of copper and molybdenum sulfides were calculated. The average particle size of copper sulfide and molybdenum disulfide powders was about 50 nm and 80 nm, respectively.

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43

Коzyrev, N. A., R. E. Kryukov, A. S. Nepomnyaschikh, A. A. Usol’tsev, and М. V. Popova. "V. Development of new powder wires for building-up. A powder wire based on dust of gas cleaning systems of silicomanganese." Ferrous Metallurgy. Bulletin of Scientific , Technical and Economic Information, no. 9 (September 25, 2018): 101–6. http://dx.doi.org/10.32339/0135-5910-2018-9-101-106.

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A new powder wire developed by using dust of gas cleaning systems of silicomanganese production plant and powder of gas cleaning systems of aluminum production at different proportion of components. As components the following was used: dust of gas cleaning systems of aluminum production plant, % (mas.): 21–46.23 Al2O3; 18–27 F; 8–15 Na2O; 0.4–6 K2O; 0.7–2.3 CaO; 0.5–2.48 Si2O; 2.1–3.27 Fe2O3; 12.5–30.2 Ctotal; 0.07–0.9 MnO; 0.06–0.9 MgO; 0.09–0.19 S; 0.1–0.18 P, and dust of gas cleaning systems of silicomanganese production plant, % (mas.): 2.43 Al2O3; 1.32 Na2O; 5.56 K2O; 6.4 CaO; 29.19 SiO2; 0.137 BaO; 7.54 MgO; 0.23 S; 0.04 P; 1.067 Fe; 27.69 Mn; 2.687 Zn; 3.833 Pb.The building-up was done under a flux, made of slag of silicomanganese plant of Zapadno-Sibirsky steel-works, havin the chemical composition (%, mas.): 6.91–9.62 Al2O3; 22.85–31.70 CaO; 46.46–48.16 SiO2; 0.27–0.81 FeO; 6.48–7.92 MgO; 8.01–8.43 MnO; 0.28–0.76 F; 0.26–0.36 Na2O; 0.62 K2O; 0.15–0.17 S; 0.01 P. The building-up mode selected. Samples wear tests were carried out at machine 2070 СМТ-1. Chemical composition of the built-up metal was determined at spectrometer ДФС-71. The hardness of built-up layers was measured by hardness meter МЕТ-ДУ. The estimation of nonmetallic inclusions was made as per GOST 1778– 70 by optical microscope Olympus GX-51.Quality indices studied and coefficients of manganese recovery at different proportions of components calculated. Statistical processing of the study results was made, statistical curves of influence of component compositions on properties of built-up layer constructed.

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Katagiri, Kazumune, Ryuya Takaya, Koichi Kasaba, Kyoji Tachikawa, Yutaka Yamada, Satoshi Shimura, Naoki Koshizuka, and Kazuo Watanabe. "Stress–strain effects on powder-in-tube MgB2tapes and wires." Superconductor Science and Technology 18, no. 12 (November 7, 2005): S351—S355. http://dx.doi.org/10.1088/0953-2048/18/12/021.

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45

Nogueira, Natacha Andréia, Anne Hitome Yonamine, Dayse Iara dos Santos, Jung Ho Kim, and Shi Xue Dou. "Characterization of Superconducting BSCCO/CaSiO₃ and BSCCO/CaZrO₃ Ag PIT Wires." Advanced Materials Research 975 (July 2014): 106–10. http://dx.doi.org/10.4028/www.scientific.net/amr.975.106.

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The addition of two compounds, calcium silicate and calcium zirconate was tested, in the preparation of Bi: 2212 silver sheathed wires by powder-in-tube method, which were successfully tested previously in processing chips. The wires were treated in an atmosphere of O2/Ar using partial melting method. The characterizations were structural and on their electrical and magnetic properties. As the results, transition temperatures were higher than the expected for this stage, ranged from 105K (BSCCO880) to 116K (+Si883). The critical current densities encountered in transport and magnetization measurements were improved in comparison with the wires without addition.

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46

Jiang, Jing Hua, Ai Bin Ma, Xin Du Fan, Ming Zi Gong, and Liu Yan Zhang. "Sherardizing and Characteristic of Zinc Protective Coating on High-Strength Steel Bridge Cable Wires." Advanced Materials Research 97-101 (March 2010): 1368–72. http://dx.doi.org/10.4028/www.scientific.net/amr.97-101.1368.

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Zinc protective coatings on high carbon SWRH82B-1 steel were sherardized to markedly improve corrosion resistance of the high-strength steel bridge cable wires (SBCW). Sherardizing parameters have been optimized by optical microscopy (OM) /scanning electron microscopy (SEM), X-ray diffraction (XRD) and potentiodynamic polarization tests. The sherardizing coatings are composed of the loose outer layer (§-FeZn13 phase) and the dense inner layer (δ- FeZn7 phase) with higher hardness. Addition of Y2O3 activator slightly increases the corrosion resistance of sherardized steel wire in comparison with CeO2. A thicker coating corresponds to a higher sherardizing temperature or a longer heating duration, but an extra thick coating is unfavorable for thru-microcrack existed in the inner layer. Good quality of sherardized wires ( higher corrosion resistance and longer duration than conditional hot-dip-galvanized one) can be produced with the zinc-rich powder containing 7.5wt.% CeO2 activator and 25wt. % SiO2 filler under 400°Cfor 6h.

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47

Imaduddin, Agung, Cindy Al Kindi Saragih, Pius Sebleku, Sigit Dwi Yudanto, Heri Nugraha, Hariyati Lubis, Hilda Ayu Marlina, et al. "Low Critical Temperature at 10K on (Bi,Pb)-Sr-Ca-Cu-O Wire with the TiO₂ Doped Using Stainless Steel Tubes." Key Engineering Materials 855 (July 2020): 227–33. http://dx.doi.org/10.4028/www.scientific.net/kem.855.227.

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Bi-type superconductor is a high-temperature superconductor with mainly applied in the field of electricity. Silver is used as a wire sheath which causes the price of this wire production to be high. In this study Bi(Pb)-Sr-Ca-Cu-O (BPSCCO) wires were made by using stainless-steel (SS316) tubes which is cheaper and is not change its properties by the temperature of the formation of BPSCCO at 860°C. The preparation of superconducting wire is done by the Powder-In-Tube method, sintering and withdrawing/ rolling process. TiO2 powder was added to analyze the effect on the formation of BPSCCO. Based on analyzing results, there is a dominant impurity phase that has been formed, namely Fe2.5Ti0.5O4. We found that in the use of stainless-steel tubes and the TiO2 powder (5wt%), 2223 phase was not formed. Although, small amounts of Bi2Sr2CaCu2O8 (2212) and Bi10Sr10Cu5O29 (2201) phases were found. Resistance versus temperature test using cryogenic equipment results indicate that there are symptoms of a low critical temperature around 10 K. 2212 and 2201 phases are thought to cause a low critical temperature in the samples, even though the decrease in electrical resistance does not reach zero. While the morphology of superconducting wire is quite well characterized from fairly even grains and only a small amount of porosity is formed.

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48

Gusev, A. I., N. A. Kozyrev, I. V. Osetkovskiy, and A. A. Usoltsev. "Developing New Powder Wire for Surfacing Details which Works in the Wear Resistance Conditions." Materials Science Forum 927 (July 2018): 126–33. http://dx.doi.org/10.4028/www.scientific.net/msf.927.126.

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The paper presents the influence of chemical compositions and structure of the deposited metal on its hardness and wear resistance in abrasive-shock conditions. Metal Was deposited by the arc powder wire automatic welding. The studies have shown that increasing nikel contain to 0.65% in the surfaced steel and cobalt additive while reducing carbon contain to 0.17-0.23%, provides martensite and former austenite grain size disintegration. In consequence of multivariate correlation analysis, it was determined dependence to the hardness of the deposited layer and the wear resistance of the mass fraction of the elements included in the flux-cored wires of the system Fe-C-Si-Mn-Cr-Mo-Ni-V-Co. Obtained dependences could be used in predicting hardness and wear resistance of the deposited metal while changing welding metal chemical composition.

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Dandliker, R. B., R. D. Conner, and W. L. Johnson. "Melt infiltration casting of bulk metallic-glass matrix composites." Journal of Materials Research 13, no. 10 (October 1998): 2896–901. http://dx.doi.org/10.1557/jmr.1998.0396.

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The authors describe a technique for melt infiltration casting of composites with a metallic-glass matrix. We made rods 5 cm in length and 7 mm in diameter. The samples were reinforced by continuous metal wires, tungsten powder, or silicon carbide particulate preforms. The most easily processed composites were those reinforced with tungsten and carbon steel continuous wire reinforcement. The Zr41.2Ti13.8Cu12.5Ni10.0Be22.5 matrix was quenched to a glass after infiltrating the reinforcement. We analyzed the microstructure of the composites by x-ray diffraction and scanning electron microscopy. The measured porosity was less than 3% and the matrix was about 97% amorphous material.

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BALAMURUGAN, S., T. NAKAMURA, K. OSAMURA, I. MUTA, and T. HOSHINO. "ANNEALING EFFECTS ON STRUCTURAL AND SUPERCONDUCTING PROPERTIES OF MgB2/Fe WIRES." Modern Physics Letters B 18, no. 16 (July 10, 2004): 791–802. http://dx.doi.org/10.1142/s0217984904007323.

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We report the results of annealing effects on structural and superconducting properties (Tc and Jc) of various MgB 2/ Fe wires that are produced by different conditions. Good quality superconducting MgB 2/ Fe wires are fabricated by the powder-in-tube (PIT) technique at ambient pressure. XRD data confirms that they are hexagonal MgB 2 structure. All the annealed samples show higher Tc values in the range of 34.6–38.4 K with Jc higher than the as-rolled wire. The annealed samples show significant change in the Jc values as well as in micro-structural features due to variable sintering temperature. On annealing at 1050°C for 10 min, we obtain the best quality sample with a Jc of 37.2 kA/cm 2 at 33.1 K and self-field with a maximum Tc of 38.4 K. Among the samples annealed at 1050°C for 5–20 min, the 20 min sample shows lower Jc. Longer annealing time (at 1050°C) reduced Jc, indicating a possible interfacial reaction between the Fe sheath and the MgB 2 core.

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Journal articles on the topic 'Powder wires'

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