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Published in Philip A. Laplante, Comprehensive Dictionary of Electrical Engineering, 2018
peripheral device a physical mechanism attached to a computer that can be used to store output from the computer, provide input to the computer, or do both. See also I/O device. peripheral processor a computer that controls I/O communications and data transfers to peripheral devices. It is capable of executing programs much like a main computer. See also I/O channel. peripheral transfer a data exchange between a peripheral device and the main computer. peripheral unit a physical mechanism attached to a computer that can be used to store output from the computer, provide input to the computer, or do both. See also I/O device. permalloy a family of ferromagnetic alloys consisting of iron, nickel, and molybdenum that saturate at moderate flux density levels and have a low coercive force. permanent fault a fault that remains in existence indefinitely if no corrective actions are taken. permanent magnet (PM) a magnet that produces an external magnetic field by virtue of the alignment of domains inside the material and retains its magnetism after being subjected to demagnetizing fields. permanent magnet AC motor a generic term used to describe both permanent magnet synchronous motors and brushless DC motors.
Methods of Investigation and Constructional Materials
Published in Janusz Turowski, Marek Turowski, Engineering Electrodynamics, 2017
Janusz Turowski, Marek Turowski
Ferrites are semiconductors (σ = from 1 to 10−9 S/m) created from complex compounds of the ferric oxide (Fe2O3) with oxides of other bivalent metals with the general formula MeO ⋅ Fe2O3, where symbol Me means Ni, Mn, Fe, Co, Li, Mg, Zn, or Cu. They are manufactured by a onefold or twofold burning of mixture of these components in temperatures from 900°C to 1400°C. There are distinguishable soft magnetic ferrites (cores of induction coils and transformers of high frequency) and hard magnetic ferrites (permanent magnets). Ferrites with rectangular hysteresis loops have been used for manufacturing memory elements for computers, magnetic amplifiers, and so on. In magnetic amplifiers (Table 1.7), small power transformers, instrument transformers, and HF coils, apart from silicon sheets, amorphous strips, and ferrites, also so-called permalloys, are used. The permalloys are nickel–iron alloys, with a high relative magnetic permeability and contents of 35–85% of Ni, and the rest is Fe, Mo (molybdenum permalloy), Mn, Cr, or Cu. The great success of the 1980s was the previously mentioned amorphous strips of type METGLASS, so-called “metallic glass” (Table 1.7; Figure 1.24) used for magnetic cores, from low (50 Hz) to high frequency, for example, 100 kHz, and for pulse and signal transformers (alloys 2605 SC, 2605 S-3) for space vehicles of 400 Hz (2605 CO), and others [1.36].
Magnetic Lenses for Electron Microscopy
Published in Orloff Jon, Handbook of Charged Particle Optics, 2017
Permalloy is a good material to use to avoid magnetic hysteresis and to obtain high magnetic-shielding properties. There are two permalloys. One is permalloy C (78% Ni–Fe–Mo–Cu alloy) and the other permalloy B (45% Ni–Fe). The former has the highest permeability in metallic magnetic materials when it is produced as a thin sheet. The Bs of permalloy C is only 0.8 T and the material is quite sensitive to mechanical stress and heat treatment. According to the author’s experience, permalloy B is better than permalloy C as a magnetic lens material. This is because the permeability of permalloy B is high enough that it can be used in a lens, and it is not so sensitive to stress. Moreover, the Bs of permalloy B is about twice that of permalloy C (1.5 T, see Figure 4.11).
Design and actual performance of J-PARC 3 GeV rapid cycling synchrotron for high-intensity operation
Published in Journal of Nuclear Science and Technology, 2022
Kazami Yamamoto, Michikazu Kinsho, Naoki Hayashi, Pranab Kumar Saha, Fumihiko Tamura, Masanobu Yamamoto, Norio Tani, Tomohiro Takayanagi, Junichiro Kamiya, Yoshihiro Shobuda, Masahiro Yoshimoto, Hiroyuki Harada, Hiroki Takahashi, Yasuhiro Watanabe, Kota Okabe, Masahiro Nomura, Taihei Shimada, Takamitsu Nakanoya, Ayato Ono, Katsuhiro Moriya, Yoshio Yamazaki, Kazuaki Suganuma, Kosuke Fujirai, Nobuhiro Kikuzawa, Shin-Ichiro Meigo, Motoki Ooi, Shuichiro Hatakeyama, Tomohito Togashi, Kaoru Wada, Hideaki Hotchi, Masahito Yoshii, Chihiro Ohmori, Takeshi Toyama, Kenichirou Satou, Yoshiro Irie, Tomoaki Ueno, Koki Horino, Toru Yanagibashi, Riuji Saeki, Atsushi Sato, Osamu Takeda, Masato Kawase, Takahiro Suzuki, Kazuhiko Watanabe, Tatsuya Ishiyama, Shinpei Fukuta, Yuki Sawabe, Yuichi Ito, Yuko Kato, Kazuo Hasegawa, Hiromitsu Suzuki, Fumiaki Noda
We use DC septum magnets for beam injection and extraction. In particular, the magnetic field of the extraction septum magnets is quite large because it requires to kick a 3 GeV proton beam. We examined the effect of the leakage field on the extraction septum magnets and found that not only the septum magnets but also the dipole magnet, which is located on the 3-NBT line from the RCS to MLF, is a source of the leakage field [80]. In the original design, a magnetic shield was attached between the septum magnet and the vacuum chamber of the circulating line. Furthermore, a magnetic stainless steel had been used for its vacuum chamber to absorb the leakage field [37]. However, that had not been enough to completely suppress the effect of leakage field. Moreover, on the BT line, no countermeasures had been taken against the dipole magnet (Figure 8(a)). Therefore, we developed a permalloy chamber and bellows with high magnetic permeability and replaced not only the duct of the septum magnet but also all the metal ducts and bellows close to the septum magnets and dipole magnet [82]. Consequently, a sufficient shielding effect could be obtained (leakage field was reduced to 3%) and beam trajectory was successfully stabilized [83]. Figure 18 shows the COD before and after replacing the permalloy chamber.
Characterisation of electroplated Ni45Fe55 thin films on n-Si (111)
Published in Surface Engineering, 2019
A. Chenna, N. Benbrahim, L. Hamadou, S. Boudinar, A. Kadri, E. Chainet, Y. Dahmane
The Permalloy film consisting of 80%Ni and 20% Fe was the nickel–iron alloy traditionally used in the magnetic recording manufacture of those devices [10,11]. Recently significant progress was made to elaborate soft NiFe alloys with higher saturation magnetic moment by increasing Fe content in the deposit. In this context, Ni45Fe55 was introduced as a new material in the fabrication of write-heads by IBM in 1997 [12,13]. Another advantage of this almost equi-atomic FeNi alloy is that in particular conditions of deposition and annealing, a phase transformation can occur. This gives rise to the formation of a tetragonal L10 structure which exhibits remarkable magnetic properties identical to those observed in rare earth-based compounds [14,15]
Towards improved electroplating of metal-particle composite coatings
Published in Transactions of the IMF, 2020
(a). The electrical conductivity of solid films can be tailored by several different approaches. Controlled value, thin film resistors can be produced from uniform distributions of an insulator (e.g. alumina, silica or a polymer) in a conducting metal matrix, such as copper. Conducting TiC and WC particles have been codeposited in gold deposits for controlled electrical conductivity and strength.43 Such deposits can contain islands of reasonable conductivity in a matrix of high conductivity gold connector surfaces, avoiding problems of insulating spots at low current loading. CeO2 can be doped by LaO2 particles, enhancing conductivity by introducing oxide ion defects.44(b). In electrochemical technology, ionically conducting materials find use as robust solid electrolytes capable of freely transporting cations or anions while electronic conductors can prove useful as robust scale-able electrodes able to support electron transfer during oxidation or reduction.(c). Solid electrolytes for solid oxide fuel cells (SOFCs) can be produced by doping ZrO2 with yttria particles and controlled optical films of Ni-YSZ (yttria stabilised zirconia) have been characterised.45(d). diamond46 or SiC particles in nickel, cobalt or Ni-Co alloys can be used for semiconductor slicing and dicing, using moving wire or rotating disc blade tools.(e). nanostructured properties47 (a Ni-Fe alloy containing ca. 80 wt% Ni) and Permalloy-magnetite composite coatings have been deposited, having readily controlled magnetic properties.47