Elżbieta Jartych | Lublin University of Technology (original) (raw)
Uploads
Papers by Elżbieta Jartych
Journal of Metastable and Nanocrystalline Materials, 2000
ABSTRACT
Non-Crystalline and Nanoscale Materials, 1998
Materials Science-Poland, 2013
ABSTRACT The aim of this work was to prepare BiFeO3 by modified solid-state sintering and mechani... more ABSTRACT The aim of this work was to prepare BiFeO3 by modified solid-state sintering and mechanical activation processes and to investigate the structure and hyperfine interactions of the material. X-ray diffraction and Mössbauer spectroscopy were applied as complementary methods. In the case of sintering, BiFeO3 phase was obtained from the mixture of precursors with 3 and 5 % excess of Bi2O3 during heating at 1023 K. Small amounts of impurities such as Bi2Fe4O9 and sillenite were recognized. In the case of mechanical activation, the milling of stoichiometric amounts of Bi2O3 and Fe2O3 followed by isothermal annealing at 973 K resulted in formation of the mixture of BiFeO3, Bi2Fe4O9, sillenite and hematite. After separate milling of individual Bi2O3 and Fe2O3 powders, mixing, further milling and thermal processing, the amount of desired BiFeO3 pure phase was significantly increased (from 70 to 90 %, as roughly estimated). From Mössbauer spectra, the hyperfine interaction parameters of the desired BiFeO3 compound, paramagnetic impurities of Bi2Fe4O9 and sillenite were determined. The main conclusion is that the lowest amount of impurities was obtained for BiFeO3 with 3 % excess of Bi2O3, which was sintered at 1023 K. However, in the case of mechanical activation, the pure phase formed at a temperature by 50 K lower as compared to solid-state sintering temperature. X-ray diffraction and Mössbauer spectroscopy revealed that for both sintered and mechanically activated BiFeO3 compounds, thermal treatment at elevated temperature led to a partial eliminating of the paramagnetic impurities.
Thin iron films with different thickness were prepared by electrodeposition. The surface morpholo... more Thin iron films with different thickness were prepared by electrodeposition. The surface morphology of the films and their local magnetic properties were studied using optical microscopy and conversion electron Mössbauer spectroscopy (CEMS). The CEMS spectra revealed an in-plane magnetic anisotropy in the iron films. Some differences between the isomer shifts of the electrodeposited iron and ␣-Fe associated with internal stresses were observed. Besides ␣-Fe, a component with a large value of the hyperfine magnetic field was registered for iron films thinner than 180 nm. It probably originates from the iron nuclei having copper atoms in the nearest neighbourhood.
Journal of Alloys and Compounds, 2002
Structural and magnetic properties of bulk amorphous alloys Fe74Al4Ga2P12B4Si4 (A), Fe76Al4P12B4S... more Structural and magnetic properties of bulk amorphous alloys Fe74Al4Ga2P12B4Si4 (A), Fe76Al4P12B4Si4 (B), Fe80P12B4Si4 (C) and Fe74Al4Ga2P8B4Si8 (D) fabricated by a single-roller melt-spinning method were studied using X-ray diffraction (XRD), differential scanning calorimetry (DSC), magnetic measurements and Mössbauer spectroscopy (MS). The supercooled liquid region up to 45 K was determined from the DSC spectra. Magnetic and MS measurements revealed strong ferromagnetic
Using the 57Fe Mössbauer spectroscopy, a local atomic order in nanocrystalline alloys of iron wit... more Using the 57Fe Mössbauer spectroscopy, a local atomic order in nanocrystalline alloys of iron with Al, Ni, W and Mo has been determined. Alloys were prepared by mechanical alloying method. Analysis of Mössbauer spectra was performed on the basis of the local environment model in terms of Warren–Cowley parameters. It was shown that impurity atoms are not randomly distributed in the volume of the first and the second co-ordination spheres of 57Fe nuclei and they form clusters.
Journal of Metastable and Nanocrystalline Materials, 2000
ABSTRACT
Non-Crystalline and Nanoscale Materials, 1998
Materials Science-Poland, 2013
ABSTRACT The aim of this work was to prepare BiFeO3 by modified solid-state sintering and mechani... more ABSTRACT The aim of this work was to prepare BiFeO3 by modified solid-state sintering and mechanical activation processes and to investigate the structure and hyperfine interactions of the material. X-ray diffraction and Mössbauer spectroscopy were applied as complementary methods. In the case of sintering, BiFeO3 phase was obtained from the mixture of precursors with 3 and 5 % excess of Bi2O3 during heating at 1023 K. Small amounts of impurities such as Bi2Fe4O9 and sillenite were recognized. In the case of mechanical activation, the milling of stoichiometric amounts of Bi2O3 and Fe2O3 followed by isothermal annealing at 973 K resulted in formation of the mixture of BiFeO3, Bi2Fe4O9, sillenite and hematite. After separate milling of individual Bi2O3 and Fe2O3 powders, mixing, further milling and thermal processing, the amount of desired BiFeO3 pure phase was significantly increased (from 70 to 90 %, as roughly estimated). From Mössbauer spectra, the hyperfine interaction parameters of the desired BiFeO3 compound, paramagnetic impurities of Bi2Fe4O9 and sillenite were determined. The main conclusion is that the lowest amount of impurities was obtained for BiFeO3 with 3 % excess of Bi2O3, which was sintered at 1023 K. However, in the case of mechanical activation, the pure phase formed at a temperature by 50 K lower as compared to solid-state sintering temperature. X-ray diffraction and Mössbauer spectroscopy revealed that for both sintered and mechanically activated BiFeO3 compounds, thermal treatment at elevated temperature led to a partial eliminating of the paramagnetic impurities.
Thin iron films with different thickness were prepared by electrodeposition. The surface morpholo... more Thin iron films with different thickness were prepared by electrodeposition. The surface morphology of the films and their local magnetic properties were studied using optical microscopy and conversion electron Mössbauer spectroscopy (CEMS). The CEMS spectra revealed an in-plane magnetic anisotropy in the iron films. Some differences between the isomer shifts of the electrodeposited iron and ␣-Fe associated with internal stresses were observed. Besides ␣-Fe, a component with a large value of the hyperfine magnetic field was registered for iron films thinner than 180 nm. It probably originates from the iron nuclei having copper atoms in the nearest neighbourhood.
Journal of Alloys and Compounds, 2002
Structural and magnetic properties of bulk amorphous alloys Fe74Al4Ga2P12B4Si4 (A), Fe76Al4P12B4S... more Structural and magnetic properties of bulk amorphous alloys Fe74Al4Ga2P12B4Si4 (A), Fe76Al4P12B4Si4 (B), Fe80P12B4Si4 (C) and Fe74Al4Ga2P8B4Si8 (D) fabricated by a single-roller melt-spinning method were studied using X-ray diffraction (XRD), differential scanning calorimetry (DSC), magnetic measurements and Mössbauer spectroscopy (MS). The supercooled liquid region up to 45 K was determined from the DSC spectra. Magnetic and MS measurements revealed strong ferromagnetic
Using the 57Fe Mössbauer spectroscopy, a local atomic order in nanocrystalline alloys of iron wit... more Using the 57Fe Mössbauer spectroscopy, a local atomic order in nanocrystalline alloys of iron with Al, Ni, W and Mo has been determined. Alloys were prepared by mechanical alloying method. Analysis of Mössbauer spectra was performed on the basis of the local environment model in terms of Warren–Cowley parameters. It was shown that impurity atoms are not randomly distributed in the volume of the first and the second co-ordination spheres of 57Fe nuclei and they form clusters.