A commercially pure (c.p.) nickel powder was consolidated by Medium-Frequency Electrical Resistance Sintering (MF-ERS). In this consolidation technique, a pressure and the heat released by a high-intensity and low-voltage electrical current are concurrently applied to a metal powder mass. A nickel powder with a high tap porosity (86%) and a low applied pressure (only 100 MPa) is chosen in order to be able to obtain compacts with different levels of porosity, to facilitate the study of the porosity influence on the compact properties. The influence of current intensity and heating time on the global porosity values, the porosity and microhardness distribution, and the electrical conductivity of the sintered compacts is studied. The properties of the compacts consolidated by MF-ERS are compared with the results obtained by the conventional powder metallurgy route, consisting of cold pressing and furnace sintering. A universal equation to describe the porosity influence on all the analyzed properties of powder aggregates and sintered compacts is proposed and validated.
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http://dx.doi.org/10.3390/ma13092131 | DOI Listing |
Neuroinformatics
January 2025
Shanghai Berry Electronic Technology Co., Ltd., Shanghai, 200000, China.
In recent years, the modulation of brain neural activity by applied electromagnetic fields has become a hot spot in neuroscience research. Transcranial direct current stimulation (tDCS) and transcranial alternating current stimulation (tACS) are two common non-invasive neuromodulation techniques. However, conventional tACS has limited stimulation effects in the deeper parts of the brain.
View Article and Find Full Text PDFJ Bodyw Mov Ther
October 2024
Postgraduate Program in Physical Education Federal Technological University of Paraná, Physical Education Department, Curitiba, Paraná, Brazil. Electronic address:
Pacing Clin Electrophysiol
December 2024
Department of Cardiology, Nagoya City University Graduate School of Medicine, Nagoya, Japan.
Micromachines (Basel)
July 2024
Department of Physics, Craiova University, A. I. Cuza Street 13, 200585 Craiova, Romania.
This paper presents the fabrication and characterization of plane capacitors utilizing magnetodielectric materials composed of magnetizable microfibers dispersed within a silicone oil matrix. The microfibers, with a mean diameter of about 0.94 μm, comprise hematite (α-FeO), maghemite (γ-FeO), and magnetite (FeO).
View Article and Find Full Text PDFMaterials (Basel)
August 2024
Faculty of Pharmacy, University of Medicine and Pharmacy Craiova, Petru Rareș 2, 200349 Craiova, Romania.
This study aims to develop low-cost, eco-friendly, and circular economy-compliant composite materials by creating three types of magnetorheological suspensions (MRSs) utilizing lard, carbonyl iron (CI) microparticles, and varying quantities of gelatin particles (GP). These MRSs serve as dielectric materials in cylindrical cells used to fabricate electric capacitors. The equivalent electrical capacitance () of these capacitors is measured under different magnetic flux densities (B≤160 mT) superimposed on a medium-frequency electric field ( = 1 kHz) over a period of 120 s.
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