Wyniki wyszukiwania - BazTech

1

Experimental and numerical investigations and optimisation of grain-oriented silicon steel mechanical cutting process

Patyk Radosław, Bohdal Łukasz, Gontarz Szymon

Acta Mechanica et Automatica

|

2022

|

Vol. 16, no. 3

292--300

EN

The process of mechanical cutting of magnetic materials has many advantages in the form of high efficiency with reduced process costs in relation to other cutting technologies; no thermal stresses in the material, which significantly deteriorate the magnetic properties; or the possibility of shaping materials taking into account long cutting lines. In industrial practice, it is very difficult to ensure appropriate conditions for the cutting process and its proper control. Currently, there are no data on the selection of technological parameters of the mechanical shear slitting process of grain-oriented silicon steel in terms of the obtained cutting surface quality and the obtained magnetic properties of the workpiece. The article presents the possibilities of forecasting the characteristic features of the cut edge and selected magnetic properties of grain-oriented silicon steel. For this purpose, proprietary numerical models using FEA (Finite Element Analysis) were used. Then, experimental studies were carried out, and the optimisation task was developed. The developed results enable the correct selection of technological parameters of the process, ensuring the appropriate quality of the cut edge of steel and minimal interference with the magnetic properties.

2

Modelowanie właściwości elektromagnetycznych materiałów nadprzewodnikowych

Sosnowski Jacek

Inżynieria Elektryczna

|

2021

|

nr 5

28--31

PL

W artykule przedstawiono wybrane prace teoretyczno-obliczeniowe zrealizowane przez Autora w Instytucie Elektrotechniki, poświęcone modelowaniu właściwości elektromagnetycznych materiałów nadprzewodnikowych. Przedyskutowano opracowane modele teoretyczne dotyczące transportu prądu przez materiały nadprzewodnikowe zarówno nisko jak i wysokotemperaturowe.

3

Effect of milling time on microstructure of cobalt ferrites synthesized by mechanical alloying

Tomiczek Anna E.

Archives of Materials Science and Engineering

|

2021

|

Vol. 111, nr 1

5--13

EN

Purpose: of this paper is to determine the effect of manufacturing conditions, especially milling time, on the microstructure and phase composition of CoFe2O4 cobalt ferrite. Design/methodology/approach: Cobalt ferrite (CoFe2O4) has been synthesised from a stoichiometric mixture of CoCo3 and α-Fe2O3 powders in a high energy planetary mill. Annealing at 1000°C for 6 hours after milling was used to improve the solid-state reaction. Calcinated samples were analysed by X-ray diffraction (XRD), and transmission electron microscopy (TEM). The relationship between the milling time of powders, their microstructure, as well as their properties were evaluated. Particles size distribution and scanning electron microscopy (SEM) with energy-dispersive X-ray spectroscopy (EDX) examination were also made. Findings: CoFe2O4 ferrites were successfully synthesized by mechanical alloying of α-Fe2O3 and CoCO3 powders. The powder particles had undergone morphological changes with the increasing milling time. However, the milling time does not affect the ferrite formation rate. It is expected that the improvement of fabrication parameters can further enhance the properties of cobalt ferrite presented in this work. Research limitations/implications: Contribute to research on the structure and properties of cobalt ferrites manufactured by mechanical alloying. Practical implications: The reactive milling and subsequently annealing is an efficient route to synthesise cobalt ferrite powder. However, using steel milling equipment risks powder contamination with iron and chromium from the vials and balls. Originality/value: The results of the experimental research of the developed ferrite materials served as the basis for determining material properties and for further investigation.

4

Koncepcja wykorzystania surowców pochodzących z recyklingu do wykonania kompozytowych materiałów ekranujących pole elektromagnetyczne

Jakubas Adam

Przegląd Elektrotechniczny

|

2020

|

R. 96, nr 12

182--185

PL

Współczesny przemysł poszukuje nowych materiałów funkcjonalnych o takich samych lub lepszych właściwościach użytkowych przy jednoczesnym zmniejszeniu obciążenia środowiska naturalnego. Grupa innowacyjnych materiałów, takich jak kompozyty oraz odpowiednia technologia ich produkcji spełnia te oczekiwania. Przeprowadzone badania wstępne wskazują na możliwość zastosowania opracowanej metody do wytwarzania kompozytu metalowo-polimerowego na konstrukcyjne panele i obudowy ekranujące pole elektromagnetyczne.

EN

Modern industry is looking for new functional materials with the same or better functional properties while reducing the burden on the natural environment. A group of innovative materials such as composites, which are a combination of components with different and complementary properties and the appropriate technology of their production meets these expectations. The preliminary studies carried out indicate the possibility of using a developed method of producing a metal / polymer composite for the construction panels and casings covering the electromagnetic field.

5

Structural optical and magnetic properties of transition metal doped ZnO magnetic nanoparticles synthesized by sol-gel auto-combustion method

Sarfraz Madiha, Ahmed Nasar, Khizar-ul-Haq, Shahida Shabnam, Khan M. A.

Materials Science Poland

|

2019

|

Vol. 37, No. 2

280--288

EN

Transition metals, such as chromium (Cr) and manganese (Mn) doped zinc oxide (ZnO) magnetic nanoparticles, were synthesized via sole gel auto-combustion method. The prepared magnetic (Zn1−(x+y)MnxCryO, where x, y = 0, 0.02, 0.075) nanoparticles were calcined in an oven at 6000 °C for 2 hours. The morphologies of the nanoparticles were investigated using different techniques. X-ray diffraction (XRD) analysis revealed that the hexagonal wurtzite structure of the synthesized nanoparticles was unaffected by doping concentration. The crystallite size measured by Scherrer formula was in the range of 32 nm to 38 nm at different doping concentrations. Nanosized particles with well-defined boundaries were observed using a field emission scanning electron microscopy (FE-SEM). Fourier transform infrared (FT-IR) spectra showed a wide absorption band around 1589 cm−1 in all the samples, corresponding to the stretching vibration of zinc and oxygen Zn–O bond. A blue shift in optical band gaps from 3.20 eV for ZnO to 3.08 eV for Zn0.85Mn0.75Cr0.75 O nanoparticles was observed in diffuse reflectance spectra, which was attributed to the sp-d exchange interactions. The field-dependent magnetization M-H loops were measured using vibrating sample magnetometer (VSM). The VSM results revealed diamagnetic behavior of the ZnO nanoparticles which changed into ferromagnetic, depending on the doping concentration and particle size. The compositions of Zn, Cr, Mn and O in the prepared samples were confirmed by using the energy dispersive X-ray spectroscopy (EDX). Our results provided an interesting route to improve magnetic properties of ZnO nanoparticles, which may get significant attention for the fabrication of magnetic semiconductors.

6

Doktor Dariusz Mazany – inżynier uniwersalny

Chrzan K. L.

Napędy i Sterowanie

|

2018

|

R. 20, nr 6

100--103

PL

W referacie przedstawiono nietypową karierę zawodową dra inż. Dariusza Mazanego. Już podczas przygotowywania pracy magisterskiej zwrócił uwagę opiekunów swym zaangażowaniem i samodzielnością. Wspólna praca doktorska, wykonywana wraz z Tomaszem Jantą, została ukończona bardzo szybko, zaledwie po 3 latach. Po obronie doktoratu następne 11 lat pracy na Politechnice Wrocławskiej nie były najlepszym okresem. Dopiero po przejściu do ABB Dolmel w 1992 r., początkowo jako stażysta, nastąpił najbardziej twórczy okres w zawodowym życiu Dariusza Mazanego. Do dzisiaj jest on wspominany w tej firmie jako genialny inżynier.

EN

In this paper the unconventional professional career of Dariusz Mazany Ph.D. was described. His angagement in the work and self-dependence were noticed by supervisers. The doctor thesis worked out together with Tomasz Janta was finished very quickly, only just after three years. After getting Ph. D. title, the next 11 years work at Wroclaw University of Technology were not the best period in his professional career. It is only when he joined the ABB Dolmel in 1992, initially as occupaing junior, the most creative period in Dariusz Mazany’s live began. Till now he is remembered in this company (now General Electric Wroclaw) as an engineer of genius.

7

Analiza charakterystyk tarczowego silnika indukcyjnego wykorzystującego różne materiały magnetyczne rdzeni stojana i wirnika

Wolnik T.

Maszyny Elektryczne : zeszyty problemowe

|

2017

|

Nr 2 (114)

189--195

PL

Z uwagi na zwiększenie efektywności energetycznej, ograniczenie kosztów produkcji lub zwiększenie gęstości mocy maszyn elektrycznych, poszukiwane są rozwiązania konstrukcyjne z wykorzystaniem różnych materiałów magnetycznych. Celem niniejszej pracy jest przedstawienie i analiza wyników pomiarowych z badań silnika tarczowego indukcyjnego wykorzystującego 3 różne rdzenie magnetyczne stojana lub wirnika tj. stojan wykonany z taśmy amorficznej, stojan i wirnik wykonany z blachy M470-50A oraz wirnik wykonany z litej stali.

EN

Due to the need for increased of energy efficiency, reduction of production costs or increased of power density in electrical machines the construction solutions using different magnetic material are researched. The purpose of this paper is to present and analyze the test results of axial flux induction motor equiped with 3 different stator or rotor magnetic cores. These are stator made of amorphous tape, stator and rotor made of M470-50A sheet and rotor made of solid steel.

8

Safe transport of magnets by air freight

Kozłowski A.

Logistyka

|

2017

|

nr 5

35--39

PL

Artykuł przedstawia problematykę właściwej interpretacji przesyłek zawierających materiały magnetyczne, jako materiały niebezpieczne w transporcie lotniczym. Autor na podstawie własnego przypadku nadania przesyłki zawierającej magnesy opisuje sposób pomiaru pola magnetycznego emitowanego z przesyłki oraz procedurę formalną jej klasyfikacji do jednego z trzech typów określających poziom zagrożenia, zgodnie z wymaganiami IATA. W pracy przedstawiono sposoby ograniczania emisji pola magnetycznego na zewnątrz przesyłki poprzez zastosowanie ekranowania. Niezależnie od wielkości pola magnetycznego emitowanego z przesyłki, rozważono stopień rzeczywistego zagrożenia dla urządzeń nawigacyjnych współczesnych samolotów, dochodząc do ciekawych wniosków i spostrzeżeń.

EN

This paper presents the consideration of proper interpretation of shipments containing magnetic materials as hazardous materials in air transport. The author, on the basis of his own case of sending a package containing magnets, introduces the way of measuring the magnetic field emitted from the shipment as well as describes the formal procedure for its classification into one of the three hazard classification types, as required by IATA. The methods of reducing the magnetic field emission outside the shipment by applying magnetic shielding is shown in the paper. Regardless of the magnitude of the magnetic field emitted from the shipment, the degree of actual danger to the navigation instruments of modern aircraft has been considered, coming to interesting conclusions and observations.

9

Electromagnetic launcher aviation gun of the future

Adamski M., Skura K., Adamski M.

Journal of KONES

|

2017

|

Vol. 24, No. 4

7--16

EN

The electromagnetic rail launcher is a type of high-energy weapon that uses a strong magnetic field to project missiles. To create this field, a current pulse source is needed to provide sufficiently high voltages and currents. The study thoroughly examines the principle of electromagnetic operation of the rail launcher, with particular emphasis on how to achieve the highest electromagnetic field strength. The analysis has been subjected to the source of the impulse current and the tendency of their development in the near future. The subject of the appropriate rails selection and their mutual arrangement has been touched up to attain adequate strength against the harmful effects associated with the flow of high currents. Considerations have been taken to protect the rails from the harmful effects of large-scale current flows, and the topic of the projectile itself to the electromagnetic field was raised. The rapid development of technology over the last few years indicates that high-energy weapons will be the basic weapon of all types of forces in the near future. The development of electromagnetic railroads requires the solution of many mechanical problems and harmful phenomena.

10

Wyznaczanie mocy strat w rdzeniu dławika pracującego w przetwornicy boost

Detka K., Górecki K.

Zeszyty Naukowe Akademii Morskiej w Gdyni

|

2016

|

nr 95

117--128

PL

W artykule rozważano problem wyznaczania mocy strat w dławiku pracującym w przetwornicy boost. Przeanalizowano literaturowe zależności, uwzględniające straty mocy w rdzeniu i w uzwojeniu elementów magnetycznych oraz obliczono moce strat w rdzeniu i w uzwojeniu wybranych dławików. Wykorzystując skupiony model termiczny, obliczono temperaturę rdzenia, a uzyskane wyniki porównano z wynikami pomiarów. Badania przeprowadzono dla dławika zawierającego rdzeń, wykonany ze sproszkowanego żelaza przy dwóch wartościach częstotliwości kluczowania. Z przeprowadzonych badań wynika, że całkowite straty mocy w dławiku są znacznie większe od sumy strat mocy w rdzeniu i uzwojeniu obliczonych na podstawie wzorów literaturowych.

EN

The paper considers the problem of calculating the power losses in the inductor operating in the boost converter. The literature dependences take into account losses in the core and in the windings of the magnetic elements was analyzed and calculated losses in the core and the winding. Based on the thermal model the temperature of inductor core is calculated and obtained results are compared with the results of measurements. The research were conducted for the inductor containing the core made of powder iron at two values of frequency. Obtained results show that the total power losses of inductor is much greater than the sum of the power losses in the core and in the winding calculated based on the literature formulas.

11

Rozwój technologii magnetycznych w wydobyciu gazu łupkowego

Zawadzki J., Bogacki J.

Systemy Wspomagania w Inżynierii Produkcji

|

2016

|

z. 1 (13)

25--37

PL

W pracy zaprezentowano obecne i potencjalne możliwości zastosowania materiałów i metod magnetycznych w poszukiwaniach i eksploatacji złóż gazu łupkowego. Ponadto, w nawiązaniu do głównego celu, naszkicowano sposoby poszukiwań, a także eksploatacji złóż gazu łupkowego, w tym omówiono zasadę procesu szczelinowania hydraulicznego.

EN

The paper presents the current and potential use of magnetic materials and methods of shale gas exploration and exploitation. Furthermore, with reference to the main objective, the principle of the hydraulic fracturing process, as a way of shale gas exploration, was outlined.

12

One step paired electrochemical synthesis of iron and iron oxide nanoparticles

Ordoukhanian J., Karami H., Nezhadali A.

Materials Science Poland

|

2016

|

Vol. 34, No. 3

655--658

EN

In this study, a new one step paired electrochemical method is developed for simultaneous synthesis of iron and iron oxide nanoparticles. iron and iron oxide are prepared as cathodic and anodic products from iron (ii) sulfate aqueous solution in a membrane divided electrolytic cell by the pulsed current electrosynthesis. Because of organic solvent-free and electrochemical nature of the synthesis, the process could be considered as green and environmentally friendly. The reduction of energy consumption and low cost are the other significant advantages of this new method that would have a great application potential in the chemical industry. The nanostructure of prepared samples was characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The magnetic properties were studied by vibrating sample magnetometer (VsM).

13

A new method for quantifying the nanoscale magnetic domains

Li Z., Hong Y., Zhang J., Li X.

Materials Science Poland

|

2016

|

Vol. 34, No. 4

924--927

EN

In this work, a signal transformation method to quantitatively analyze fine magnetic structures in nanometer length scales measured by magnetic force microscopy has been developed. Nanosized magnetic domains, magnetic charges with reconstructed polarity as well as quantified magnetic field contours of samples (such as ordered FePt dot arrays, hard magnetic thin films and polycrystalline La0.7Sr0.3 MnO3 (LSMO) films ) were investigated based on the basic principles of deconvolution and micromagnetics. The present technique is crucial for the analysis of fine magnetic structures, and is important for the development of next generation magnetic recording industry.

14

Solvothermal synthesis and magnetic properties of beta-Co2P nanorods

Li T., Liao J. P., Wang Y. F.

Materials Science Poland

|

2015

|

Vol. 33, No. 2

312--316

EN

Hexagonal high temperature phase beta-Co2P nanorods with a diameter of around 50 nm were synthesized via a mild solvothermal route. The reaction was carried out at 180 degrees C using cobalt chloride hexahydrate (CoCl2 center dot 6H(2)O) as Co source and yellow phosphorous as P source. The composition, structure as well as morphology were characterized by X-ray diffraction (XRD), X-ray photoemission spectroscopy (XPS) and transmission electron microscopy (TEM). The magnetic susceptibility curve indicates that the beta-Co2P nanorods show canted antiferromagnetic state, different from the paramagnetic state of orthorhombic low temperature phase beta-Co2P.

15

Pomiary dynamicznych pętli histerezy konstrukcyjnej stali prototypowej

Koteras D., Tomczuk B.

Maszyny Elektryczne : zeszyty problemowe

|

2015

|

Nr 3 (107)

151--154

PL

W niniejszej pracy przedstawiono sposób pomiaru dynamicznych pętli histerezy dla stali o nowatorskim składzie przeznaczonej na nabiegunniki maszyn elektrycznych, a szczególnie generatorów wiatrowych. Pomiary wykonano dla dwóch częstotliwości zasilania, a mianowicie f1=10 Hz oraz f2=50 Hz. Porównano wartości strat mocy w rdzeniu otrzymane z całkowania pola powierzchni pętli histerezy oraz metodą bezpośredniego pomiaru poboru mocy ze źródła zasilającego uzwojenie próbki stalowej.

EN

The measurement tests of the dynamic hysteresis loops for the innovative composition casting steel. In measurements designed for poles of the electrical machines, especially wind generators, were presented in this paper. The measurements were performed for two frequencies of power supplying f1=10 Hz and f2=50 Hz. The power core losses obtained by integration of the dynamic hysteresis loop surfaces have been compared with those obtained by direct measurements of the source power supplying the steel probe winding.

16

Determination Of Power Loss In Fe-Based Soft Magnetic Composites

Jankowski B., Kapelski D., Ślusarek B., Szczygłowski J.

Archives of Metallurgy and Materials

|

2015

|

Vol. 60, iss. 2B

1411--1415

EN

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.

17

Parametric optimization of NiFe2O4 nanoparticles synthesized by mechanical alloying

Hajalilou A, Hashim M, Ebrahimi-Kahrizsangi R., Kamari H M, Kanagesan S.

Materials Science Poland

|

2014

|

Vol. 32, No. 2

281--291

EN

In this study, the Taguchi robust design method is used for optimizing ball milling parameters including milling time, rotation speed and ball to powder weight ratio in the planetary ball milling of nanostructured nickel ferrite powder. In fact, the current work deals with NiFe2O4 nanoparticles mechanochemically synthesized from NiO and Fe2O3 powders. The Taguchi robust design technique of system optimization with the L9 orthogonal array is performed to verify the best experimental levels and contribution percentages (% r) of each parameter. Particle size measurement using SEM gives the average particle size value in the range of 59 – 67 nm. X-ray diffraction using Cu Ka radiation is also carried out to identify the formation of NiFe2O4 single phase. The XRD results suggest that NiFe2O4 with a crystallite size of about 12 nm is present in 30 h activated specimens. Furthermore, based on the results of the Taguchi approach the greatest effect on particle size (42.10 %) is found to be due to rotation speed followed by milling time (37.08 %) while ball to powder weight ratio exhibits the least influence.

18

Synthesis of Magnetic Materials from Natural Carbon Precursors ‒ a Review

Zubrik A., Lovas M., Matik M., Stefusova K., Hredzak S.

Inżynieria Mineralna

|

2014

|

R. 15, nr 2

127--130

EN

Preparation methods, properties and utilization of magnetic materials based on natural carbon precursors are summarized in this short review. Magnetic material is defined as the composite material consist of carbon substance coming from natural precursor such as coal/biomass and magnetic substance. Various processes can be applied to prepare magnetic materials. Pyrolysis of the biomass/coal together with iron ions and coprecipitation of Fe2+/Fe3+ with charcoal are mostly used methods for synthesis of magnetic biochar. The pyrolysis is defined as a thermal degradation in the absence of oxygen, which converts a raw material into different reactive intermediate products: solid (char), liquid and gaseous products. Especially, microwave pyrolysis of natural materials with iron ions is one of the best techniques offering homogenous, rapid and energetically efficient heating system to produce magnetic material. After the synthesis, iron particles are incorporated to the pore carbon structure and can form (especially in thermal process) microparticles as well as nanosized particles with defined structure possessing magnetic properties, high pore volume and high specific surface area. Magnetic carbon is used mainly as an excellent sorbent material mainly for organic pollutants and heavy metals. Moreover, solid/liquid magnetic separation as a rapid and effective technique can be applied in removal of used magnetic biochar from aqueous solution after sorption process. After sorption and pre-concentration, the magnetic sorbent can be effectively regenerated e.g. by high temperature (organic pollutants such as azodyes, pesticides) and leaching methods (inorganic contaminates).

PL

W tym krótkim przeglądzie streszczono metody przygotowywania, właściwości i wykorzystanie materiałów magnetycznych opartych na maturalnych prekursorach węgla. Materiały magnetyczne są zdefiniowane jako materiał kompozytowy składający się z substancji węglowej pochodzących z naturalnych prekursorów takich jak węgiel/biomasa i substancji magnetycznej. Różne procesy mogą być zastosowane do przygotowania materiałów magnetycznych. Piroliza biomasy/węgla wraz z jonami żelaza i współstrąceniem Fe2+/Fe3+ z węglem drzewnym są najczęściej używanymi metodami syntezy magnetycznego biowęgla. Piroliza jest zdefiniowana jako rozkład termalny bez udziału tlenu, który przetwarza surowiec w różne reaktywne produkty pośrednie: stałe (karbonizat), płynne i gazowe produkty. Szczególnie piroliza mikrofalowa materiałów naturalnych z jonami żelaza jest jedną z najlepszych technik oferującą homogeniczny, szybki i energetycznie efektywny system ogrzewania do produkcji materiałów magnetycznych. Po syntezie, jony żelaza są włączane do struktury porowatej węgla i mogą tworzyć (szczególnie w procesach termicznych) mikrocząsteczki jak i nanocząsteczki o zdefiniowanej strukturze posiadające właściwości magnetyczne, dużą objętość porów i dużą powierzchnię właściwą. Węgiel magnetyczny jest używane głównie jako doskonały sorbent głównie dla organicznych zanieczyszczeń i metali ciężkich. Ponadto, magnetyczna separacja substancji stałych od ciekłych może być zastosowana jako szybka i efektywna technika usuwania zużytego biowęgla magnetycznego z roztworów wodnych po procesie sorpcji. Po sorpcji i wstępnej koncentracji, sorbent magnetyczny może być efektywnie zregenerowany np. za pomocą wysokiej temperatury (zanieczyszczenia organiczne takie jak barwniki azowe, pestycydy) i metodami ługowania (zanieczyszczenia nieorganiczne).

19

Magnetyzm i materiały magnetyczne

Gierlotka S.

Wiadomości Elektrotechniczne

|

2013

|

R. 81, nr 4

34--35

20

One-pot synthesis of magnetic γ-Fe2O3 nanoparticles in ethanol-water mixed solvent

Wu Z. G., Wang Y.

Materials Science Poland

|

2013

|

Vol. 31, No. 4

577--580

EN

Maghemite (g-Fe2O3) nanoparticles were synthesized via a low-temperature solution-based method using ferric chloride hexahydrate and ferrous chloride tetrahydrate as precursors in the mixed solvent of ethanol and water. X-ray diffraction, energydispersive X-ray spectroscopy, and Fourier transform infrared spectroscopy revealed that the obtained product was pure gFe2O3. Transmission electron microscopy showed the morphology of the nanoparticles to be approximately spherical in shape with an average diameter of 11 nm. Magnetization measurements indicated the dry powders exhibit ferromagnetic behavior with a maximum saturation magnetization of 41.1 emu/g at room temperature.