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Structure and Magnetic Properties of Bi5Ti3FeO15 Ceramics Prepared by Sintering, Mechanical Activation and Edamm Process. A Comparative Study

Jartych E., Pikula T., Mazurek M., Franus W., Lisinska-Czekaj A., Czekaj D., Oleszak D., Surowiec Z., Aksenczuk A., Calka A.

Archives of Metallurgy and Materials

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2016

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Vol. 61, iss. 2A

869--874

EN

Three different methods were used to obtain Bi5Ti3FeO15 ceramics, i.e. solid-state sintering, mechanical activation (MA) with subsequent thermal treatment, and electrical discharge assisted mechanical milling (EDAMM). The structure and magnetic properties of producedBi5Ti3FeO15 samples were characterized using X-ray diffraction and Mössbauer spectroscopy. The purest Bi5Ti3FeO15 ceramics was obtained by standard solid-state sintering method. Mechanical milling methods are attractive because the Bi5Ti3FeO15 compound may be formed at lower temperature or without subsequent thermal treatment. In the case of EDAMM process also the time of processing is significantly shorter in comparison with solid-state sintering method. As revealed by Mössbauer spectroscopy, at room temperature theBi5Ti3FeO15 ceramics produced by various methods is in paramagnetic state.

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Structure and hyperfine interactions in multiferroic Aurivillius Bi m+1Ti3Fe m−3O3m+3 compounds prepared by mechanical activation

Mazurek M., Oleszak D., Czekaj D.

Materials Science Poland

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2014

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Vol. 32, No. 4

676--681

EN

The aim of the study was to determine the structure and hyperfine interactions of Bim+1Ti3Fem−3O3m+3 multiferroic Aurivillius compounds prepared by mechanical activation process. X-ray diffraction and Mössbauer spectroscopy were applied as complementary methods. After the process of mechanical milling, desired Aurivillius phases were not formed, thus, thermal treatment needed to be applied. Heating the product of mechanical activation up to 993 K allowed to obtain Aurivillius phases with relatively large amount of non-reacted hematite. However, after the material was annealed at an elevated temperature of 1073 K, the content of not fully synthesized hematite was significantly reduced. Mössbauer spectroscopy confirmed that Aurivillius compounds remain in paramagnetic state at room temperature.

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Structure and hyperfine interactions of multiferroic Bim+1Ti3Fem-3O3m+3 ceramics prepared by mechanical activation

Mazurek M., Jartych E., Oleszak D.

Nukleonika

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2013

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Vol. 58, No. 1

143-147

EN

The structure and hyperfine interactions in the Bi5Ti3FeO15, Bi6Ti3Fe2O18 and Bi7Ti3Fe3O21 multiferroic ceramics were studied using X-ray diffraction and Mössbauer spectroscopy. Samples were prepared by mechanical activation process in a high-energy ball mill from a mixture of TiO2, Fe2O3 and Bi2O3 oxides as polycrystalline precursor materials. The mechanical milling process was completed by thermal processing. A pure single-phased material was obtained in the case of Bi7Ti3Fe3O21 compound. The proposed mechanical activation technology allows to produce the Aurivillius compounds at lower temperature, by about 50 K, as compared to the solid-state sintering method.

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Hyperfine interactions and irreversible magnetic behavior in multiferroic Aurivillius compounds

Jartych E., Gąska K., Przewoźnik J., Kapusta C., Lisińska-Czekaj A., Czekaj D., Surowiec Z.

Nukleonika

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2013

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Vol. 58, No. 1

47-51

EN

In this work investigations of structure and magnetic properties of conventionally sintered Bim+1Ti3Fem.3O3m+3 compounds with 4 less-than or equal to m less-than or equal to 8 were performed using X-ray diffraction, Mossbauer spectroscopy and vibrating sample magnetometry. Room-temperature Mossbauer spectra of the compounds correspond to a paramagnetic state, however, low temperature measurements (80 K) reveal the antiferromagnetic state with a residual paramagnetic phase. Temperature dependencies of magnetic susceptibility,chi sigma(T), provided magnetic ordering temperatures and revealed an irreversibility in Aurivillius compounds with m greater-than or equal to 5. In the case of Bi5Ti3FeO15 compound the chi sigma(T) dependence shows a paramagnetic behavior down to 2 K. The Bi6Ti3Fe2O18 compound reveals a magnetic ordering at 11 K. The compounds with m = 6-8 show a magnetic ordering at temperatures higher than 200 K. Highly irreversible character of their temperature dependencies of chi sigma indicates a spin-glass type disordered magnetism with frustration due to a random distribution of Fe on Ti at their sites.

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Mössbauer studies of Bi5Ti3FeO15 electroceramic prepared by mechanical activation

Mazurek M., Jartych E., Oleszak D.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 9b

256-258

EN

The present work involves the structure analysis and the determination of hyperfine interactions parameters of multiferroic Bi5Ti3FeO15 electroceramic, prepared by high-energy ball milling of polycrystalline precursors (mixture of the Bi2O3, TiO2 and Fe2O3 simple oxides). This analysis was performed by X-ray diffraction and Mössbauer spectroscopy.

PL

W pracy przedstawiono wyniki badań dla multiferroicznej elektroceramiki Bi5Ti3FeO15 otrzymanej podczas procesu aktywacji mechanicznej (mielenie wysokoenergetyczne polikrystalicznych proszków Bi2O3, TiO2 i Fe2O3). Badania struktury i oddziaływań nadsubtelnych przeprowadzono metodami dyfrakcji promieniowania X oraz spektroskopii efektu Mössbauera.