Wyniki wyszukiwania - Biblioteka Nauki

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Nanocrystalline iron based powder cores for high frequency applications

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Gramatyka P. , Kolano-Burian A. , Kolano R. , Polak M.

Journal of Achievements in Materials and Manufacturing Engineering

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2006

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tom Vol. 18, nr 1-2

99--102

EN

Purpose: The aim of this paper was to develop a various nanocrystalline powder cores with different polymers as a binder and investigate their magnetic properties (especially permeability and power losses) at high frequency range. Design/methodology/approach: Numerous experimental techniques were used to characterize starting powders: laser particles analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and Mössbauer spectrometry (MS). The dynamic magnetic properties at the frequency range from 50 Hz up to 100 kHz of nanocrystalline iron based powder cores were measured using computerized hysteresis loop tracer Remacomp C-100 and Ferrometr device. Findings: It was found from the experimental studies, that nanocrystalline powder cores proved to be suitable for high frequency applications. Their frequency dependences are comparable to that of permalloy or carbonyl iron powder cores but shows smaller power losses. Research limitations/implications: Further studies should be undertaken in order to produce high density composites with good soft magnetic properties and to find a good compromise between mechanical and magnetic properties for power electronics applications. Practical implications: Developed nanocrystalline powder cores with permeability’s below 100 are potential candidates for a variety of industrial applications, such as electromagnetic interference filters, radio frequency coupling devices, filter inductors and radio frequency tuning cores. Originality/value: Soft magnetic materials have recently regained interest as inductive component which is a result of better raw materials, more developed technologies and a need for the materials from electrical micromotors and low power motors for automation, robotics and other equipments. The present study complements and extends earlier investigations of polymer bonded powders.

2

Wpływ mikrostruktury miedzioniklu CuNi25 na zakres efektu temperatury minimalnej plastyczności (TMP)

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Nowosielski R. , Sakiewicz P. , Gramatyka P.

Rudy i Metale Nieżelazne

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2005

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tom R. 50, nr 1

16-20

PL

Na podstawie przeprowadzonych wysokotemperaturowych prób rozciągania stwierdzono wpływ mikrostruktury, wielkości i kształtu ziarna na plastyczność oraz zakres występowania wysokotemperaturowe- go minimum plastyczności w stopie CuNi25. Badania metalograficzne potwierdziły dane literaturowe stwierdzające, że pękanie w zakresie temperatury minimalnej plastyczności (TMP), przebiega po granicach ziaren oraz najczęściej zarodkuje w obszarze łączenia się granic trzech ziaren oraz przecięcia bliźniaków z granicą ziarna. Analiza składu chemicznego w obszarach granic ziaren i pęknięć wykazuje lokalnie powstawanie obszarów nierównowagowych o zmiennym podwyższonym lub obniżonym, w stosunku do średniej, stężeniu Cu i Ni. Fakt ten może być przyjęty jako jedna z przyczyn pękania materiałów, w zakresie efektu TMP, i potwierdzenie mechanizmów niejednorodnego odkształcenia oraz jego lokalizacji.

EN

On the grounds of the ductility test at elevated temperature was found that exist relation between microstructure, shape and size of grain and effect of ductility minimum temperaturę (DMT), in single-phase cupronickel CuNi25 alloy. Metallographic research confirmed literature studies that cracks nucleate at points of meeting two or three boundaries of grains and cross-cut of twins with border of grain. The non-uniform of chemical composition concentrating in areas of grain boundaries and cracks at elevated temperature was investigated by linear and point Cu and Ni analysis (EDS). This analysis shows that locally areas of not equilibrium formation and concentrates at this places. This fact can be accepted as one of the reason of cracking and non-homogeneous deformation and its location at DMT.

3

Wpływ procesów nanokrystalizacji szkieł metalicznych typu FeCuNbSiB na własności magnetyczne.

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Nowosielski R. , Gramatyka P. , Griner S.

Archiwum Nauki o Materiałach

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2003

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tom T. 24, nr 4

357-371

PL

W pracy przedstawiono wyniki badań wpływu parametrów procesów nanokrystalizacji termicznej, nanokrystalizacji mechanicznej oraz kombinowanej nanokrystalizacji termiczno-mechanicznej na kształtowanie własności magnetycznych stopu Fe73,5Cu1Nb3Si13,5B9. Przeprowadzone badania pozwoliły określić wpływ czasu obróbki cieplnej na przebieg nanokrystalizacji i zmiany własności magnetycznych szkła metalicznego typu FINEMET. Równocześnie określono wpływ czasu wysokoenergetycznego mielenia, temperatury wstępnej i końcowej obróbki cieplnej na przebieg nanokrystalizacji i strukturę uzyskanego materiału proszkowego, średnią średnicę ziaren proszku oraz jego własności magnetyczne.

EN

The correlation between structure and magnetic properties of FINEMET alloy was studied. The samples were prepared by three techniques: controlled thermal nanocrystallization (heat treatment); high-energy ball milling of nanocrystalline ribbons (obtained by annealing at 823 K for 1 h) and high-energy ball milling of amorphous ribbons. Strong influence of annealing temperatures, annealing time and milling time on structure, powder particle size and soft magnetic properties of Fe73,5Cu1Nb3Si13,5B9 alloy was observed.

4

Soft magnetic composite based on nanocrystalline Fe73.5Cu1Nb3Si13.5B9 and Fe powders

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Gramatyka P. , Nowosielski R. , Sakiewicz P. , Raszka T.

Journal of Achievements in Materials and Manufacturing Engineering

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2006

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tom Vol. 15, nr 1-2

27--31

EN

Purpose: The main aim of this study is the producing of toroidal shape soft magnetic composite cores from nanocrystalline Fe73,5Si13,5Nb3Cu1B9 and Fe powders insulated with epoxy resin and to investigate the density and content of powder response of the soft magnetic properties. Design/methodology/approach: Examination of magnetic properties of SMC was made on the Ferrometr device. The magnetic parameters were determined from hysteresis loops, permeability as a function of applied magnetic field and core losses as a function of magnetic induction characteristics. Findings: The results of experimental studies demonstrated a correlation between the increase density and the improvement of the magnetic properties of the composite. Research limitations/implications: The measurements of magnetic permeability should be conducted in a wide range of frequency. Practical implications: The usability of composite cores as inductive component in electronic industry depends upon further investigations. Originality/value: Soft magnetic composites based on iron powders are essential elements in today’s electronic world. As far as we know, composites materials based on nanocrystalline material as soft magnetic materials have not been examined yet.

5

Recycling of waste electrical and electronic equipment

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Gramatyka P. , Nowosielski R. , Sakiewicz P.

Journal of Achievements in Materials and Manufacturing Engineering

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2007

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tom Vol. 20, nr 1-2

535-538

EN

Purpose: This paper describes the current status of waste electrical and electronic equipment recycling and disposal in Europe, and its impact on the environment, human health and the economy. Design/methodology/approach: The production of electric and electronic equipment is one of the fastest growing areas. This development has resulted in an increase of WEEE. Increased recycling of WEEE is supposed to limit the total quantity of waste going to final disposal. Findings: based on comprehensive bibliography, this article reviewed the implementation of strategies of WEEE treatment and the recovery technologies of WEEE. Research limitations/implications: Further studies should be undertaken in order to develop integrated WEEE recycling and disposal systems. Practical implications: In view of the environmental problems involved in the management of WEEE, many countries and organizations have drafted national legislation to improve the reuse, recycling and other forms of recovery of such waste so as to reduce disposal. Recycling of WEEE is an important subject not only from the point of waste treatment but also from the recovery of valuable materials. The study of WEEE properties is important for a further recycling and eventual reuse.

6

Magnetic properties of polymer bonded nanocrystalline powder

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Gramatyka P. , Nowosielski R. , Sakiewicz P.

Journal of Achievements in Materials and Manufacturing Engineering

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2007

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tom Vol. 20, nr 1-2

115-118

EN

Purpose: The aim of this paper was to develop a dielectromagnetic based on nanocrystalline Fe73.5Cu1Nb3Si13.5B9 powder bonded with organo-silicon polymer and to investigate the powder particle size and content of polymer response of the magnetic properties. Design/methodology/approach: The dynamic magnetic properties at the frequency range from 50 Hz up to 100 kHz of nanocrystalline iron based powder cores were measured using computerized hysteresis loop tracer Remacomp C-100 and Ferrometr device. Findings: It was found from the experimental studies, that nanocrystalline powder cores proved to be suitable for high frequency applications. Their frequency dependences are comparable to that of carbonyl iron powder cores but shows smaller power losses. Research limitations/implications: Further studies should be undertaken in order to produce high density composites with good soft magnetic properties and to find a good comprise between mechanical and magnetic properties for power electronics applications. Practical implications: Developed nanocrystalline powder cores with permeability's below 100 are potential candidates for a variety of industrial applications, such as electromagnetic interference filters, radio frequency coupling devices, filter inductors and radio frequency tuning cores. Originality/value: Soft magnetic materials have recently regained interest as inductive component which is a result of better raw materials, more developed technologies and a need for the materials from electrical micromotors and low power motors for automation, robotics and other equipments. The present study complements and extends ealier investigations of polymer bonded powders.