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tom T. 21, Nr 3 (165)
210--213
PL
W pracy badano właściwości magnetyczne kompozytu wytworzonego przy różnym czasie nacisku. Kompozyty do badań wytworzone zostały na bazie amorficznych cząstek stopu Fe62Co12Gd4Ni3B19 i żywicy Epidian 100. Gradacja wypełniacza użyta do wytworzenia kompozytu była tego samego rzędu. Stosowany wypełniacz o strukturze amorficznej jest magnetykiem i cechuje się dobrymi właściwościami magnetycznie miękkimi. Należy nadmienić, że każdy dysk z kompozytu zawierał taką samą ilość metalicznego wypełniacza. Oznacza to, że obserwowana zmiana właściwości magnetycznych, a w szczególności wartość pola koercji oraz magnetycznej polaryzacji nasycenia jest jedynie wynikiem zmian jednego z parametrów ich wytwarzania, czyli czasu prasowania. W wyniku przeprowadzonych badań stwierdzono, że wydłużony czas prasowania mieszanki żywicy Epidian 100 z amorficznymi drobinami znacząco wpływa na poprawę właściwości magnetycznie miękkich uzyskanego kompozytu.
EN
The aim of this paper were studies of the magnetic properties of the composite produced at different times of force pressure. The investigated composites were produced based on particles of amorphous Fe62Co12Gd4Ni3B19 alloys and Epidian 100 resin. The gradation of the filler used to form the composite was in the same order of magnitude. The used filler is amorphous magnetic material characterized by a good soft magnetic properties. It should be noted that each composite disk contained the same amount of metal filler. This means that the observed change in the magnetic properties, especially the coercive field and the saturation magnetic polarization is only a result of changing one of the parameters of their manufacture, namely pressing time. The research found that extended time of pressure of the resin with amorphous particles significantly improved the soft magnetic properties of the resulting composite.
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tom Vol. 73, nr 1
5--12
EN
Purpose: The paper presents results of structural and magnetic properties of Fe78Si11B11 and Fe78Si9B11Y2 alloys in the form of ribbons. The effect of addition of yttrium on the structure and magnetic properties was investigated. Design/methodology/approach: The investigated samples were prepared in the form of ribbons using the melt-spinning method. The material structures were investigated using X-ray diffractometry, Mössbauer spectroscopy and scanning electron microscopy. The magnetic properties were studied using using vibrating magnetometer. Findings: Samples were fabricated using rapid cooling at a rotating copper wheel. Images of fractures of investigated samples obtained by decohesion using same magnifications are similar. The distinct vein like structure or the husk structure are not visible thought they are typical of amorphous and nanocrystalline materials with a high degree of internal stress. Mössbauer spectrum is typical as for amorphous materials that are ferromagnetic. It consists of six lines forming a Zemman's sextet. The hyperfine induction field distribution obtained for this sample shows clearly separated two components: low- and high-field. After the introduction of 2% at. Y to the alloy Fe78Si11B11 in place of Si partial crystallization occurred. The shape of the initial magnetization curves is similar and corresponds to materials with low effective anisotropy. Originality/value: The paper presents some researches of the Fe-based bulk amorphous alloys obtained by the melt-spinning method.
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tom Vol. 61, iss. 1
445--450
EN
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.
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tom Vol. 64, nr 2
97--102
EN
Purpose: The aim of this paper were studies of the structure and magnetic properties of the bulk amorphous (Fe0.61Co0.10Zr0.025Hf0.025W0.02Ti0.02B0.20)94Y6 alloy, obtained by suction-casting method. Design/methodology/approach: The microstructure of the as-quenched and annealed at 720K for 15 min samples was studied by X-ray diffractometry and Mössbauer spectroscopy. The transmission Mössbauer spectra for the powdered samples were measured at room temperature using conventional Mössbauer spectrometer working at a constant acceleration with a 57Co(Rh) radioactive source of the 70 mCi in activity. However, the low field magnetic properties such as magnetic susceptibility, its disaccommodation and core losses were measured by a transformer method using a completely automated set up. In susceptibiity and its disaccommodation studies the amplitude of the magnetizing field was 0.26 A/m. Before the measurements the samples were demagnetized in an alternating magnetic field with the amplitude decreasing from 800 A/m to zero during 1.1 s. The core losses and magnetic permeability as a function of the magnetizing field amplitude for the frequency up to 1 kHz were measured. Findings: The rods were fully amorphous which was confirmed by X-ray diffractometry and Mössbauer spectroscopy. On the basis studies of magnetization in high magnetic fields we have stated, that in investigated alloy, in the as-quenched state and after annealing, only structural defects called quasi-dislocation dipoles are present. The disaccommodation phenomenon in the investigated samples of (Fe0.61Co0.10Zr0.025Hf0.025W0.02Ti0.02B0.20)94Y6 alloy , related with the directional ordering of atomic pairs near the free volumes, is not observed. On the basis of the changes in core losses, it can be stated that the studied alloy at low frequencies the total losses are comparable with those observed in classical silicon-iron alloys. Practical implications: Using a vibrating sample magnetometer the magnetization in high magnetic fields was studied (in magnetic field up to 2 T). All investigations carried out for samples in the as-quenched state and after annealing. Originality/value: This paper presents studies relating to the structure and magnetic properties of the bulk amorphous (Fe0.61Co0.10Zr0.025Hf0.025W0.02Ti0.02B0.20) alloy, obtained in the form of rods with 2 mm in diameter and 2 cm long by the suction casting method
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tom Vol. 73, nr 2
80--85
EN
Purpose: The aim of this study was to conduct studies of the magnetic properties for a massive amorphous alloy Fe61Co10Ti3Y6B20. Design/methodology/approach: The investigated samples were prepared in the form of rods by using the suction-casting method. The material structures were investigated using X-ray. The magnetic properties were studied using a completely automated set up for measuring susceptibility and its disaccommodation. The magnetization as a function of magnetizing field was measured using magnetic Faraday's weight as a part of magnetocaloric effect studies. Findings: In the framework of this study, the structure and magnetic properties of the solid amorphous alloy Fe61Co10Ti3Y6B20 was examined. On the basis of the of X-ray diffraction obtained material was found to be amorphous alloy. Magnetic studies were carried out using a fully computerized system for magnetic susceptibility measures and its disaccommodation. It was showed that both susceptibility curve and isochoric disaccommodation curve maximum occurs in the transition from the state of ferromagnetic material into a paramagnetic state. This peak is called the Hopkinson maximum. From the curves of the magnetic susceptibility as a function of the temperature the value of the Curie temperature was established to about 550 K. Using the measurements of magnetisation as a function of magnetic field strength Arrott curves were constructed. The positive slope of the curves demonstrates the fact that the phase transition ferro-para is of the second kind. Using the magnetization curves the change of the magnetic entropy was determined. The biggest change of the magnetic entropy occur near the Curie temperature. Research limitations/implications: Based on studies carried out as part of this work it was found that the magnetic properties of investigated alloy, ie. magnetic susceptibility and its disaccommodation, are showing a clear change near the Curie temperature. Originality/value: The study of magnetic properties and their behavior in the vicinity of the Curie temperature.
EN
The paper presents studies of microstructure, magnetic and mechanical properties of composite prepared on the basis of the bulk amorphous materials. The results presented in this work indicate, that it is possible to generate electrotechnical composite material having a rather high microhardness, which are built in more than 95 wt % of amorphous ferromagnetic metal powder, and the remaining part is Epidian 100 resin. Examined composites were fully amorphous and homogeneous. The homogeneity of the material from which ferromagnetic particles are prepared for composites is an important parameter, which ensures the same properties throughout the entire volume of the composite. Combination of amorphous particles of fraction 100÷200 microns, with the polymeric binder, resulted in a microhardness reduction in relative to the bulk amorphous plate. With increasing weight content of the resin, in the composite, the saturation magnetization significantly decreased, while the coercivity field increased over twentyfold.
PL
W pracy przedstawiono wyniki badań struktury, właściwości magnetycznych i mechanicznych przeprowadzonych dla kompozytów wytworzonych z amorficznych cząstek połączonych żywicą epoksydową. Otrzymane wyniki wskazują, że jest możliwość wytworzenia elektrotechnicznego materiału kompozytowego o dość dużej mikrotwardości zbudowanego w ponad 95% z ferromagnetycznego metalicznego amorficznego proszku, resztę stanowi żywica epidian 100. Badane materiały kompozytowe były w pełni amorficzne i homogeniczne, co oznacza, że rozdrobniony materiał uzyskany z amorficznych płytek miał dobrą jednorodność. Jednorodność materiału, z którego wytwarza się cząstki ferromagnetyczne dla kompozytów jest istotnym parametrem, zapewniającym zachowanie takich samych właściwości w całej objętości kompozytu. Zespolenie amorficznych cząstek o frakcji 100÷200 μm polimerowym lepiszczem wpłynęło na obniżenie mikrotwardości w porównaniu z próbką w postaci płytki. Wraz ze wzrostem zawartości żywicy w kompozycie znacznie zmniejszyła się magnetyzacja nasycenia, natomiast pole koercji wzrosło ponad dwudziestokrotnie.
EN
The fabrication method and magnetic properties of Sm12.5Co66.5Fe8Cu11Si2 alloy are presented in this article. The samples were produced by rapid quenching of the liquid alloy onto a rotating, copper wheel (the so-called ‘melt-spinning’ method) and they had a thin ribbon shape. The microstructure of the samples was investigated by measurements of diffraction patterns for powdered samples, in order to obtain data from the entire volume of the sample. It was found, that samples were composed of different amounts of Sm2Co17, SmCo5 and SmCo7 phases, depending on the linear velocity of the copper wheel used during the fabrication process. The magnetic measurements were performed using a vibrating sample magnetometer (LakeShore VSM) working with an external magnetic field of up to 2 T. It was found that the obtained ribbons displayed relatively good hard magnetic properties, such as remanence μ0MR, and high resistance to demagnetization fields JHC.
PL
W pracy badano wpływ warunków wytwarzania na własności magnetyczne i skład fazowy stopu Sm12.5Co66.5Fe8Cu11Si2 w stanie po zestaleniu. Próbki stopu zostały otrzymane przy użyciu metody szybkiego chłodzenia na miedzianym wirującym bębnie (ang. melt-spinning) i miały postać cienkich taśm. Badania struktury zostały wykonane przy użyciu dyfraktometru rentgenowskiego. W celu otrzymania danych z całej objętości próbki badania składu fazowego zostały przeprowadzone dla sproszkowanych próbek. Dla otrzymanych dyfraktogramów przeprowadzono analizę jakościową i ilościową (Rietvelda) składu fazowego. Na podstawie otrzymanych wyników stwierdzono, że próbki składały się z różnych zawartości faz Sm2Co17, SmCo5 i SmCo7. Nawet niewielkie zmiany w szybkości chłodzenia skutkują znacznymi różnicami w składzie fazowym stopu. Własności magnetyczne próbek zostały wyznaczone przy użyciu magnetometru wibracyjnego (LakeShore VSM), przy zastosowaniu zewnętrznego pola magnetycznego o wartości 2T. Różna zawartość faz oraz rozmiary ziaren w otrzymanych próbkach powodowały znaczne różnice w wartościach parametrów magnetycznych.
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Content available remote Properties of chirped periodic layered medium with metamaterial layers
45%
EN
Purpose: The purpose of the article was to investigate the absorption and reflectance properties of chirped periodic layered medium with metamaterial layers. Design/methodology/approach: The use of the algorithm TMM (Transfer Matrix Method) allows to determine the absorption and reflectance for the quasi one-dimensional multilayer structures. Can be analysed structure constructed with RHM (right-handed materials) and LHM (left-handed materials) with layers of any thickness and arranged in any way. It is possible to analyse lossy dispersive materials. Findings: In all the cases studied linear shift in the peaks with an increase in the k coefficient was observed. In all cases there was a shift to higher wavelengths. Noted an increase in the intensity and broadening half-width of the peaks. Research limitations/implications: The simulation was carried out only for the binary structure in the visible light range. Practical implications: Computer simulations allow us to design material with specified properties at a lower cost. The use of chirped periodic layered media allows to shift and broadening of the peak in the required range of work for mirrors or filter. Originality/value: Absorption and reflectance for chirped periodic layered systems using metamaterials layers have not yet been thoroughly investigated. Research can contribute to the implementation of mirrors with specific nonlinear properties.
PL
W pracy przedstawiono wyniki badań strukturalnych oraz magnetycznych kompozytów otrzymanych na bazie stopu o składzie chemicznym Fe67Co10Ni1W2B20 i żywicy epoksydowej. Badane próbki miały kształt walców oraz posiadały ten sam udział objętościowy żywicy epoksydowej (klej Epidian 100). Wytworzony stop o składzie chemicznym Fe67Co10Ni1W2B20 został niskoenergetycznie rozkruszony w moździerzu, a następnie poddany analizie sitowej i podzielony na trzy frakcje: 20-50 µm, 50-100 µm oraz 100-200 µm. Tak otrzymane proszki stopów zostały połączone z żywicą epoksydową. Określono wpływ wielkości cząstek proszku i osnowy na właściwości magnetyczne kompozytów.
EN
The paper presents the results of the structural and magnetic studies of composites obtained on the Basic of the alloy Fe67Co10Ni1W2B20 and epoxy resin (glue Epidian 100). The resulting alloy with chemical composition Fe67Co10Ni1W2B20 was low-energy crushed in a mortar, and then subjected to a sieve analysis and divided into three fractions: 20-50 microns, 50-100 microns and 100-200 microns. The thus obtained alloy powders were combined with an epoxy resin. Were identified: powder particle size and the magnetic properties of the matrix composites.
12
Content available remote Infrared transmission in aperiodic structures
45%
EN
Purpose: The analysis of the electromagnetic wave transmission having a wave length near infrared propagating in multilayer structures made of materials GaP and CaF2. Analyzed was the influence of periodicity distribution of layers in the material properties and the presence of photonic forbidden gap for selected wavelengths of the electromagnetic wave. Design/methodology/approach: Maps transmission, which was performed by the analysis were obtained using a matrix method. Was investigated wave propagation wavelength range of infrared radiation in periodic binary multilayers and aperiodic Severin and Thue-Morse superlattices. Findings: It has been shown the structure of the transmission band depending on the type of polarization of the multilayer system. Properties of Thue-Morse superlattices were similar to binary superlattices but differed from the behavior of electromagnetic waves in aperiodic Severin superlattices. Research limitations/implications: The simulation was not considered the impact of losses in the material for propagating electromagnetic wave. Practical implications: Multilayer materials, which have photonic band gap, can be used as filters for electromagnetic radiation can improve the performance of night vision or electromagnetic waves multiplexers. Originality/value: Transmission properties of multilayers were examined in visible light but not for infrared light.
EN
In this paper, the results of investigations are presented, into the microstructure and magnetic properties of the following amorphous alloys in the as-quenched state: Fe82Zr7Nb2Cu1B8 and Fe86Zr4Y3Nb1Cu1B5. The studied material was produced in the form of thin ribbons of 3 mm width and 20 μm thickness. The structure and microstructure of the samples have been investigated by means of Mössbauer spectrometry and X-ray diffractometry. In addition, the magnetic properties of these materials have been determined, i.e. the low-field magnetic susceptibility, and the magnetisation as a function of temperature and magnetising field. On the basis of the performed investigations, it has been found that a minor change in the quantities of elements favouring amorphisation, such as: Zr and Y, has an influence on the value of the Curie temperature and the magnetic properties of the resulting alloys. It should be noticed that the changes, introduced in the chemical composition of the alloys, don’t change the combined volume of these elements, i.e. Zr7 and Zr4Y3.
PL
W pracy przedstawiono wyniki badań struktury i mikrostruktury oraz właściwości magnetycznych stopów amorficznych Fe82Zr7Nb2Cu1B8, Fe86Zr4Y3Nb1Cu1B5 w stanie po zestaleniu w postaci cienkich taśm o szerokości 3 mm i grubości 20 μm. Strukturę oraz mikrostrukturę próbek badano wykorzystując spektrometrię mössbauerowską i spektroskopię rentgenowską. Dokonano również pomiarów właściwości magnetycznych, takich jak: niskopolowa podatność magnetyczna, magnetyzacja w funkcji temperatury i funkcji pola magnesującego. Na podstawie przeprowadzonych badań stwierdzono, że niewielka zmiana amorfizatorów takich jak: cyrkon i itr znacząco wpływa na wartość temperatury Curie, a także wpływa na właściwości magnetyczne tych stopów. Należy zwrócić szczególną uwagę na fakt, że wprowadzone zmiany składowe nie zmieniają ich ilości tzn. Zr7 i Zr4Y3.
EN
The paper presents the results of study of filtration properties of aperiodic multilayer systems constructed according to the Thue-Morse algorithm. The study consisted of electromagnetic wave propagation simulation in range of 300÷700 nm depending on the angle of incidence relative to the normal of superlattice's surface. First simulation of propagation for the ideal structure was performed in which the thickness of the individual layers were 150 nm, and then defects in the form of small variations in the thickness of the layer (in the range of ± 7%) were applied. The study revealed that the band gaps are highly correlated with the thicknesses of the individual layers, the type and arrangement of used material. With the increase in generation also increases the number of transmission bands, and their half-width decreases. Manufacture inaccuracies have small influence on the transmission maxima but strongly affect the interband spaces.
PL
W pracy przedstawiono wyniki badań właściwości filtracyjnych dla aperiodycznych układów wielowarstwowych zbudowanych zgodnie z algorytmem Thue-Morse’a. Badania polegały na symulacji propagacji fali elektromagnetycznej o długościach leżących w przedziale od 300÷700 nm w zależności od kąta padania względem normalnej do powierzchni badanej supersieci. Przeprowadzono symulację propagacji dla struktury idealnej, w której grubości poszczególnych warstw wynosiły 150 nm, a następnie wprowadzano defekty w postaci niewielkiej zmiany grubości warstw (w zakresie ±7%). Badania ujawniły, że przerwy pasmowe są silnie skorelowane z grubością poszczególnych warstw, typem użytego materiału oraz jego ułożeniem. Wraz ze wzrostem liczby generacji rośnie także liczba pasm transmisji, a ich szerokość połówkowa maleje. Niedokładności wytworzenia w niewielki sposób wpływają na maksima transmisji, ale silnie oddziałują na przestrzenie międzypasmowe.
15
Content available remote Transmission in combination of structures
38%
EN
Purpose: The paper investigated the effect of the combination of two structures on the transmission of electromagnetic waves as a multilayer filter. Examined how the combination of two structures affect the properties of the filter. As a component materials of structures used both right-handed material (RHM) and left-handed (LHM). Design/methodology/approach: Analysis was performed using a matrix method for calculating the superlattice transmission. The influence of combination of two types of multilayer systems: periodic (binary superlattice) and aperiodic (Severin’s and Thue-Morse’s superlattices). Findings: Studies have shown the structure of the transmission band of the structures, which is dependent on the polarization of the incident wave. Combination of various structures are not commutative, and therefore their transmission maps are not equal. Research limitations/implications: The structures analyzed in the work consisted of a lossless material, isotropic and non-dispersive. An important analysis would be lossy dispersive materials. You should also examine the impact would have a separating layer structure and the influence of defects on transmission properties of superlattices. Practical implications: The test structures may be used as filters of electromagnetic radiation. Placing the filter characteristics of the two structures allows pre-filtering an electromagnetic wave, in order to obtain a structure suitable for applications. Originality/value: The paper shows how combination of two periodic and aperiodic structures affect the propagation of electromagnetic waves in a multi-layered system. The analysis was based on the determination of unpolarized transmission maps for complex structures.
16
Content available remote The influence of pressure to the stresses inside the plough body
38%
EN
Purpose: The aim of the study was to examine the structure of the plough body and determining areas most susceptible to damage. Design/methodology/approach: The analysis was performed using Finite Element Analysis (FEA) in AutoDesk Inventor Professional 2015. Characteristics of the materials that make up the individual parts correspond to the materials used for the production in the AGRO-MASZ company. Findings: Studies have shown the greatest stress distribution in the mouldboard shin, mouldboard and leg. Highest stresses on mouldboard occur in the area, which is also the most exposed to the abrasive wear. Research limitations/implications: It seems important to carefully examine the areas of the largest abrasive wear analysed plows bodies. Practical implications: FEA analysis allows pre-testing of the properties of the part before manufacturing. Creating a model and adding forces and pressures to it allows for huge savings for companies. It is possible to find weaknesses in designed products before they cause problems. In the production of bodies for ploughs critical is the selection of suitable material and then subjecting it to specialist heat treatment. Originality/value: Article allowed the estimation of the plow body stress of AGRO-MASZ company, the analysis of which has not yet been published. The studies allow for the continuous improvement of the quality of ploughs.
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Content available remote The influence of extinction coefficient on transmission in binary multilayer
32%
EN
Purpose: The influence of the extinction coefficient for transmission, reflectance and absorption in multilayer binary. Reps cluster was equal to 7 It was built of two types of materials. First was a NaCl equivalent with a refractive index described by nA=1.544-ik , and as second was GaAs lossless metamaterial equivalent Design/methodology/approach: Research was carried out using the map of: transmitting, reflectance and absorption of the electromagnetic wave. Maps determined using the matrix method. Findings: It is shown that the higher the extinction coefficient, which is responsible for the absorption of electromagnetic waves, decreases the transmittance and reflectance of the multilayer system at the same time increasing its absorption. Research limitations/implications: Would be a reasonable correlation between the results of the transmission, reflectance and absorption obtained using numerical methods with with experiment. Practical implications: Taking into account the extinction coefficient allows for a better representation of the real multilayer structures. Quasi one-dimensional superlattices can be used as filters or multiplexers electromagnetic waves. Originality/value: In the literature the most frequently analyzed lossless structure. Taking into account the extinction coefficient allows for better study the properties of the tested materials.
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