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Wyświetlanie 1-15 z 29
Tytuł:
Higher order reversal curves in some hysteresis models
Autorzy:
Chwastek, K.
Powiązania:
https://bibliotekanauki.pl/articles/140836.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
soft magnetic materials
hysteresis
modelling
Opis:
Some physical concepts important for a hysteresis model (effective field, anhysteretic magnetization) are discussed on the example of Jiles-Atherton model. The Jiles-Atherton model reveals some drawbacks, which make this model more difficult to be applied in electrical engineering. In particular, it does not describe accurately the magnetization curves after a reversal, moreover complex magnetization cycles are poorly represented. On the other hand, the phenomenological description proposed by Takács seems to be a valuable alternative to the Jiles-Atherton formalism. The concept of effective field may be easily incorporated in the description.
Źródło:
Archives of Electrical Engineering; 2012, 61, 4; 455-470
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Structure and Soft Magnetic Properties of the Amorphous Alloys: Fe61Co10Ti3-xY6+xB20 (x = 0,1)
Autorzy:
Błoch, K.
Powiązania:
https://bibliotekanauki.pl/articles/354790.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
structure
soft magnetic properties
amorphous alloys
Opis:
This paper presents studies relating to the structure, soft magnetic properties and thermal stability of the following bulk amorphous alloys: Fe61Co10Ti3-xY6+xB20 (x = 0, 1). On the basis of the performed X-ray diffraction studies and Mössbauer spectroscopy, it was found that investigated samples were amorphous in the as-cast state. The DSC curve obtained for Fe61Co10Ti2Y7B20 alloy exhibited one exothermic peak, while for the Fe61Co10Ti3Y6B20 sample, two peaks were distinguishable. The change in the chemical structure of the investigated alloys has a major effect on their soft magnetic properties; especially on coercivity and saturation magnetization. On the basis of the magnetization curves analysis, the spin wave stiffness parameter Dsp were determined for the investigated alloys.
Źródło:
Archives of Metallurgy and Materials; 2016, 61, 1; 445-450
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of Zr and Nb on the Electrical and Magnetic Properties of the Fe-Zr-Nb-B-Cu Alloy
Autorzy:
Noh, Junghyun
Park, Seungyeon
Hwang, Haejin
Lim, Kyoungmook
Powiązania:
https://bibliotekanauki.pl/articles/350932.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
soft magnetic
magnetic properties
amorphous alloy
nanocrystalline alloy
electrical properties
Opis:
The present study, aims to investigate the effect of minor Zr and Nb alloying on soft magnetic and electrical properties of Fe86 (Zrx Nb1-x )7B6 Cu1 (x=1, 0.75, 0.5, 0.25) alloys. The investigated alloys were prepared through the melt spinning process. Within the examined compositional range (Nb up to 5.25 at%, respectively), the soft magnetic properties and electrical resistivity of the alloys continuously increase with increasing Nb content. However increasing the Nb content further decreases such properties. We could confirm the influence of ratio of Zr and Nb on grain growth and crystallization fraction during crystallization by using the soft magnetic properties and electrical properties.
Źródło:
Archives of Metallurgy and Materials; 2019, 64, 3; 879-882
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Measurement and simulation of a rotational single sheet tester
Autorzy:
Müller, Fabian
Bavendiek, Gregor
Schauerte, Benedikt
Hameyer, Kay
Powiązania:
https://bibliotekanauki.pl/articles/140359.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
finite element method
magnetic hysteresis
magnetization processes
soft magnetic material
Opis:
The accurate prediction of iron losses has become a prominent problem in electromagnetic machine design. The basis of all iron loss models is found in the spatial field-locus of the magnetic flux density (B) and magnetic field (H). In this paper the behavior of the measured BH-field-loci is considered in FEM simulation. For this purpose, a vector hysteresis model is parameterized based on the global measurements, which then can be used to reproduce the measurement system and obtain more detailed insights on the device and its local field distribution. The IEM has designed a rotary loss tester for electrical steel, which can apply arbitrary BH-field-loci occurring during electrical machine operation. Despite its simplicity, the proposed pragmatic analytical model for vector hysteresis provides very promising results.
Źródło:
Archives of Electrical Engineering; 2019, 68, 1; 173-183
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mössbauer and magnetic studies of FeCoNiCuNbSiB nanocrystalline alloys
Autorzy:
Grabias, A.
Basykh, V.
Ferenc, J.
Cieślak, G.
Kulik, T.
Kopcewicz, M.
Powiązania:
https://bibliotekanauki.pl/articles/146338.pdf
Data publikacji:
2017
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
amorphous ribbons
nanocrystalline alloys
Mössbauer spectroscopy
soft magnetic properties
Opis:
Nanocrystalline Fe80–x–yCoxNiyCu1Nb3Si4B12 alloys were prepared by the annealing of amorphous ribbons. Primary crystallization of the alloys annealed at temperatures of between 500 and 550°C was studied by X-ray diffraction and Mössbauer spectroscopy. Magnetic properties of the alloys were investigated using a hysteresis loop tracer and vibrating sample magnetometer. The annealed ribbons are composed of a two-phase nanostructure consisting of bcc Fe-based grains embedded in an amorphous matrix. Conversion electron Mössbauer spectroscopy (CEMS) measurements reveal a more advanced crystallization process in the surface layers when compared with the volume of the ribbons. The degree of saturation magnetization of the nanocrystalline alloys is of about 1.5 T. The coercive fi eld varies from 1.0 to 6.5 A/m and peaks at an annealing temperature of 525°C. Magnetic softening of the nanocrystalline alloys observed after annealing at 550°C is correlated with a volume fraction of the nanocrystalline bcc phase.
Źródło:
Nukleonika; 2017, 62, 2; 79-84
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Magnetic Properties of (Nia-Znb)X Cu1-X Ferrite Nanoparticle Fabricated by Sol-Gel Process
Autorzy:
Yang, S.
Kim, J.-G.
Powiązania:
https://bibliotekanauki.pl/articles/352091.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Ni-Zn-Cu ferrite
nanoparticle
soft magnetic property
sol-gel
Opis:
In future, more mobile devices with different frequencies will be used at the same time. Therefore, it is expected that the trouble caused by wave interference between devices will be further intensified. In order to prevent this trouble, investigation of selective frequency transmission or absorption material is required. In this paper, magnetic properties of nickel-zinc-copper ferrite nano powder was researched as wave absorber. (Nia-Znb)xCu1-xFe2O4(NZCF) nanoparticles were fabricated by the sol-gel method. The influence of copper substitution on lattice parameter change was analyzed by X-ray diffraction (XRD), particle size was analyzed by scanning electron microscopy (SEM), and Magnetic properties analyzed by vibrating sample magnetometer (VSM). The NZCF and Nickel-zinc ferrite (NZF) lattice parameter difference was 0.028 Å and particle size was calculated as 30 nm with the XRD peak. The VSM results of (Ni0.3-Zn0.3)0.6Cu1-0.6Fe2O4 annealed sample at 700°C for 3hous were 58.5 emu/g (Ms), 22.8 Oe (Hc). It was the most suitable magnetic properties for wave absorber in this investigation.
Źródło:
Archives of Metallurgy and Materials; 2017, 62, 2B; 1197-1200
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wpływ zastosowania różnego rodzaju osnowy w materiałach kompozytowych na ich właściwości magnetyczne
The influence of using various type of binders in composite materials to their magnetic properties
Autorzy:
Jakubas, A.
Dąbrowski, R.
Powiązania:
https://bibliotekanauki.pl/articles/267631.pdf
Data publikacji:
2018
Wydawca:
Politechnika Gdańska. Wydział Elektrotechniki i Automatyki
Tematy:
histereza
kompozyty miękkie magnetycznie
właściwości magnetyczne
Soft Magnetic Composites
magnetic properties
processing
measurements
Opis:
W pracy przeprowadzono analizę wpływu materiału osnowy na właściwości magnetyczne miękkich materiałów kompozytowych (SMC). Badania przeprowadzono na próbkach rdzeni cylindrycznych wykonanych przez autorów z mieszaniny proszku żelaza i różnego rodzaju osnowy. Badania obejmowały wyznaczenie takich parametrów jak indukcja nasycenia Bs, natężenie koercji Hc i stratność. Pomiary wykonano przy różnej częstotliwości wymuszenia.
Soft magnetic composites are often used in the design of electromagnetic converters and electrical machines. Their popularity is due to the ease of molding and the ability to adapt to specific applications. The paper presents magnetic properties of cores made of iron powder and different type of binder. Samples were prepared by compression in temperature dependent from binder / Fe powder mix. Measurement of magnetic parameters revealed an change in magnetic properties with using various types of binders. The presented measurement data show that it is possible to produce of SMC cores with good magnetic properties, using readily available components and in uncomplicated production processes. Cylindrical cores were made with different types of binders, respectively: powder of suspense polyvinyl chloride, powder of polytetrafluoroethylene, powder of polyethylene wax and transformer oil. For the prepared samples we have determined their basic magnetic properties. The analysis of collected measurement data showed a significant relationship between SMC sample forming parameters and their magnetic properties. In addition, the measurements showed a poor dependence of the magnetic properties in developed SMC samples on the excitation frequency. The method of producing a polymer-metal composite described in the article is the subject of patent application P.420850.
Źródło:
Zeszyty Naukowe Wydziału Elektrotechniki i Automatyki Politechniki Gdańskiej; 2018, 59; 65-68
1425-5766
2353-1290
Pojawia się w:
Zeszyty Naukowe Wydziału Elektrotechniki i Automatyki Politechniki Gdańskiej
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Advances in Powder Metallurgy Soft Magnetic Composite Materials
Autorzy:
Bureš, R.
Strečková, M.
Fáberová, M.
Kollár, P.
Füzer, J.
Powiązania:
https://bibliotekanauki.pl/articles/353238.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
resin bonded SMC
soft magnetic ferrites
compaction
microwave sintering
magnetic and mechanical properties
Opis:
Powder metallurgy has grown with the expansion of various industry. Automotive industry had the most strong influence. Today, more than 90% of PM products are used in the transportation industry. Development of new materials such as magnetic materials is expected to meet the new trends of automotive industry, electric and hybrid vehicles. Soft magnetic composites (SMC) are PM materials based on ferromagnetic powder particles covered by electric insulation layer. Concept of SMC’s and PM technologies offer possibility to become faster, use higher frequencies, become smaller and denser, save more energy, achieving high permeability and lower core loss in high frequency region, which is required for soft magnetic materials. Investigation of correlations among compaction parameters, inner structure, magnetic and mechanical properties are presented.
Źródło:
Archives of Metallurgy and Materials; 2017, 62, 2B; 1149-1154
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Operating point resolved loss computation in electrical machines
Autorzy:
von Pfingsten, G.
Ruf, A.
Steentjes, S.
Hombitzer, M.
Franck, D.
Hameyer, K.
Powiązania:
https://bibliotekanauki.pl/articles/141566.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
efficiency maps
material degradation
magnetic losses
magnetic material
behaviour
soft magnetic materials
electrical machines
Opis:
Magnetic circuits of electromagnetic energy converters, such as electrical machines, are nowadays highly utilized. This proposition is intrinsic for the magnetic as well as the electric circuit and depicts that significant enhancements of electrical machines are difficult to achieve in the absence of a detailed understanding of underlying effects. In order to improve the properties of electrical machines the accurate determination of the locally distributed iron losses based on idealized model assumptions solely is not sufficient. Other loss generating effects have to be considered and the possibility being able to distinguish between the causes of particular loss components is indispensable. Parasitic loss mechanisms additionally contributing to the total losses originating from field harmonics, non-linear material behaviour, rotational magnetizations, and detrimental effects caused by the manufacturing process or temperature, are not explicitly considered in the common iron-loss models, probably even not specifically contained in commonly used calibration factors. This paper presents a methodology being able to distinguish between different loss mechanisms and enables to individually consider particular loss mechanisms in the model of the electric machine. A sensitivity analysis of the model parameters can be performed to obtain information about which decisive loss origin for which working point has to be manipulated by the electromagnetic design or the control of the machine.
Źródło:
Archives of Electrical Engineering; 2016, 65, 1; 73-86
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Subsurface structure and magnetic parameters of Fe-Mo-Cu-B metallic glass
Autorzy:
Miglierini, M.
Hasiak, M.
Bujdoš, M.
Powiązania:
https://bibliotekanauki.pl/articles/147390.pdf
Data publikacji:
2015
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
ion bombardment
metallic glasses
Mössbauer spectrometry
soft magnetic properties
surface structure
Opis:
Subsurface properties of 57Fe81Mo9Cu1B9 metallic glass were studied by conversion electron and conversion X-ray Mössbauer spectrometry. They were applied to both surfaces of the ribbons. Deviations in structural surface features are exhibited via different contents of crystalline phases, which were identifi ed as bcc-Fe and magnetite. The presence of small ferromagnetic particles was also suggested from magnetic measurements. An infl uence of irradiation with 130-keV N+ ions on surface properties of the as-quenched alloy is also discussed.
Źródło:
Nukleonika; 2015, 60, 1; 115-119
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Correlations between hyperfine magnetic field and some macroscopic magnetic quantities in mechanosynthesized CoxFeyNiz alloys
Autorzy:
Pikula, T.
Powiązania:
https://bibliotekanauki.pl/articles/147844.pdf
Data publikacji:
2013
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
CoFeNi alloys
hyperfine interactions
mechanical alloying
Mössbauer spectroscopy
soft magnetic materials
Opis:
In this work correlations between some macroscopic magnetic quantities and hyperfine magnetic field (HMF) were studied in the case of mechanosynthesized CoxFeyNiz alloys. The series of twelve samples was prepared by high energy ball milling. As the products of such process, disordered solid solutions with bcc or fcc crystalline lattice type were obtained. The magnetic measurements proved that in this case soft magnetic alloys with relatively high value of saturation magnetization were obtained. The semi-phenomenological relationship between the HMF value and the mean magnetic moment was also found for the studied samples. Moreover, correlations between some magnetic quantities and mean concentration of the 3d+4s electrons were investigated.
Źródło:
Nukleonika; 2013, 58, 1; 153-157
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Thermal annealing of soft magnetic materials and measurements of its magnetoelastic properties
Wyżarzanie materiałów magnetycznie miękkich i metody badania ich właściwości magnetosprężystych
Autorzy:
Szewczyk, R.
Bieńkowski, A.
Salach, J.
Jackiewicz, D.
Švec Sr, P.
Hasko, J.
Švec, P.
Kamiński, M.
Winiarski, W.
Powiązania:
https://bibliotekanauki.pl/articles/276803.pdf
Data publikacji:
2013
Wydawca:
Sieć Badawcza Łukasiewicz - Przemysłowy Instytut Automatyki i Pomiarów
Tematy:
materiały magnetycznie miękkie
wyżarzanie
soft magnetic materials
thermal annealing
magnetoelastic properties
Opis:
Paper presents both methods of the most advanced thermal annealing as well as available methods of testing the magnetoelastic properties of soft magnetic materials for technical applications. Selected features and conditions important for annealing of ring-shaped cores made of the magnetoelastic amorphous ribbons are described and an example of thermomagnetic processing is shown. Unified methodologies for testing of magnetoelastic properties of the frame-shaped and the ringshaped cores, for both compressive and tensile stresses are presented.
W referacie przedstawiono zarówno nową metodę relaksacji termicznej w materiałach magnetycznie miękkich, jak i metody pomiaru charakterystyk magnetosprężystych w tych magnetykach. W referacie przedstawiono także wybrane wyniki pomiaru wpływu procesu relaksacji termicznej w obecności pola magnetycznego na charakterystyki magnesowania stopów amorficznych, jak również wyniki pomiaru charakterystyk magnetosprężystych. Należy podkreślić, że z wykorzystaniem przedstawionej w pracy metodyki możliwy jest pomiar charakterystyk magnetomechanicznych zarówno w zakresie naprężeń ściskających, jak i rozciągających.
Źródło:
Pomiary Automatyka Robotyka; 2013, 17, 2; 513-518
1427-9126
Pojawia się w:
Pomiary Automatyka Robotyka
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Determination Of Power Loss In Fe-Based Soft Magnetic Composites
Wyznaczanie strat mocy w kompozytach magnetyczne miękkich na bazie żelaza
Autorzy:
Jankowski, B.
Kapelski, D.
Ślusarek, B.
Szczygłowski, J.
Powiązania:
https://bibliotekanauki.pl/articles/351809.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
magnetic materials
power losses
soft magnetic composites
materiały magnetyczne
straty mocy
miękkie kompozyty magnetyczne
Opis:
The magnetic properties of Fe-based composite materials with different particle sizes were investigated. The results of energy loss density were obtained from measurements of the static (DC) hysteresis cycles ranging from 0,2 to 1,4 T. In turn, the results of power loss density were obtained from measurements of the dynamic (AC) hysteresis cycles ranging from 20 to 400 Hz and at the maximum flux density 0,3; 0,9 and 1,3 T. Two sets of specimens was analyzed in the investigation: the specimens compacted under pressure of 800 MPa and hardened at 500°C and the specimens compacted under different pressure and hardened at 500°C. Specimens of the second set had the same density. The study confirmed the influence of particle size distribution on magnetic properties of Fe-based soft magnetic composites.
Źródło:
Archives of Metallurgy and Materials; 2015, 60, 2B; 1411-1415
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wpływ ciśnienia formowania materiałów kompozytowych na ich właściwości magnetyczne
The influence of molding pressure of the composite materials to their magnetic properties
Autorzy:
Jakubas, A.
Seme, S.
Powiązania:
https://bibliotekanauki.pl/articles/268094.pdf
Data publikacji:
2017
Wydawca:
Politechnika Gdańska. Wydział Elektrotechniki i Automatyki
Tematy:
miękkie kompozyty magnetyczne
właściwości magnetyczne
obróbka
pomiary
soft magnetic composites
magnetic properties
processing
measurements
Opis:
Miękkie kompozyty magnetyczne SMC są często stosowane w projektowaniu przetwornic i maszyn elektrycznych. Swoją popularność zawdzięczają łatwości formowania i możliwości dostosowania do konkretnych zastosowań. W p racy przedstawiono właściwości magnetyczne rdzeni wykonanych z proszku żelaza i suspensyjnego polichlorku winylu. Próbki przygotowywano przez prasowanie na gorąco mieszanki proszku PVC/Fe przy różnych ciśnieniach formowania. Na podstawie wykonanych pomiarów można stwierdzić, że wraz ze wzrostem ciśnienia formowania następuje polepszenie właściwości magnetycznych.
Soft magnetic composites are often used in the design of electromagnetic converters and electrical machines. Their popularity is due to the ease of molding and the ability to adapt to specific applications. The paper presents magnetic properties of cores made of iron powder and suspension polyvinyl chloride. The samples were prepared by hot compression of the PVC / Fe powder mix at various forming pressures. Measurement of magnetic parameters revealed an improvement in magnetic properties with increasing molding pressures. The presented measurement data show that it is possible to produce of SMC cores with good magnetic properties, using readily available components and in uncomplicated production processes. Cylindrical cores were made at different molding pressures, respectively: 234 MPa (30T), 390 MPa (50T), 507 MPa (65T). For the prepared samples we have determined their basic magnetic properties. The analysis of collected measurement data showed a significant relationship between SMC sample forming parameters and their magnetic properties. In addition, the measurements showed a poor dependence of the magnetic properties in developed SMC samples on the excitation frequency. The method of producing a polymer-metal composite described in the article is the subject of patent application P.420850.
Źródło:
Zeszyty Naukowe Wydziału Elektrotechniki i Automatyki Politechniki Gdańskiej; 2017, 54; 97-100
1425-5766
2353-1290
Pojawia się w:
Zeszyty Naukowe Wydziału Elektrotechniki i Automatyki Politechniki Gdańskiej
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The effect of anisotropy in the modified Jiles-Atherton model of static hysteresis
Autorzy:
Chwastek, K.
Szczygłowski, J.
Powiązania:
https://bibliotekanauki.pl/articles/141327.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
materiały magnetycznie miękkie
histereza
anizotropia
modelowanie
soft magnetic materials
hysteresis
anisotropy
modeling
Opis:
An extension of the modified Jiles-Atherton description to include the effect of anisotropy is presented. Anisotropy is related to the value of the angular momentum quantum number J, which affects the form of the Brillouin function used to describe the anhysteretic magnetization. Moreover the shape of magnetization dependent R(m) function is influenced by the choice of the J value.
Źródło:
Archives of Electrical Engineering; 2011, 60, 1; 49-57
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
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