TY  - JOUR
AU  - Obradović, Nina
AU  - Fahrenholtz, William G.
AU  - Filipović, Suzana
AU  - Marković, Smilja
AU  - Blagojević, Vladimir A.
AU  - Lević, Steva
AU  - Savić, Slobodan
AU  - Djordjević, Antonije
AU  - Pavlović, Vladimir
PY  - 2020
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/5344
AB  - Solid-state mechanical activation of MgO and alpha-Al2O3 powders was used to produce MgAl2O4. The cation site occupancy in the resulting MgAl2O4 spinel was investigated using different methods. Differential thermal analysis and thermal gravimetry showed that mechanical activation reduced the spinel formation temperature by around 200 degrees C, and the corresponding activation energy by about 25%. In addition, characteristic temperatures for evaporation of physisorbed water and decomposition of Mg(OH)(2) shifted to lower values, and peaks were more pronounced. Raman spectra were used to characterize the degree of inversion as a function of the sintering temperature for all of the sintered specimens, indicating that the breaking point for ordering of the crystal structure was around 1500 degrees C for non-activated samples, and 1400 degrees C for activated samples.
PB  - Springer, Dordrecht
T2  - Journal of Thermal Analysis and Calorimetry
T1  - Formation kinetics and cation inversion in mechanically activated MgAl2O4 spinel ceramics
EP  - 107
IS  - 1
SP  - 95
VL  - 140
DO  - 10.1007/s10973-019-08846-w
ER  - 

@article{
author = "Obradović, Nina and Fahrenholtz, William G. and Filipović, Suzana and Marković, Smilja and Blagojević, Vladimir A. and Lević, Steva and Savić, Slobodan and Djordjević, Antonije and Pavlović, Vladimir",
year = "2020",
abstract = "Solid-state mechanical activation of MgO and alpha-Al2O3 powders was used to produce MgAl2O4. The cation site occupancy in the resulting MgAl2O4 spinel was investigated using different methods. Differential thermal analysis and thermal gravimetry showed that mechanical activation reduced the spinel formation temperature by around 200 degrees C, and the corresponding activation energy by about 25%. In addition, characteristic temperatures for evaporation of physisorbed water and decomposition of Mg(OH)(2) shifted to lower values, and peaks were more pronounced. Raman spectra were used to characterize the degree of inversion as a function of the sintering temperature for all of the sintered specimens, indicating that the breaking point for ordering of the crystal structure was around 1500 degrees C for non-activated samples, and 1400 degrees C for activated samples.",
publisher = "Springer, Dordrecht",
journal = "Journal of Thermal Analysis and Calorimetry",
title = "Formation kinetics and cation inversion in mechanically activated MgAl2O4 spinel ceramics",
pages = "107-95",
number = "1",
volume = "140",
doi = "10.1007/s10973-019-08846-w"
}

Obradović, N., Fahrenholtz, W. G., Filipović, S., Marković, S., Blagojević, V. A., Lević, S., Savić, S., Djordjević, A.,& Pavlović, V.. (2020). Formation kinetics and cation inversion in mechanically activated MgAl2O4 spinel ceramics. in Journal of Thermal Analysis and Calorimetry
Springer, Dordrecht., 140(1), 95-107.
https://doi.org/10.1007/s10973-019-08846-w

Obradović N, Fahrenholtz WG, Filipović S, Marković S, Blagojević VA, Lević S, Savić S, Djordjević A, Pavlović V. Formation kinetics and cation inversion in mechanically activated MgAl2O4 spinel ceramics. in Journal of Thermal Analysis and Calorimetry. 2020;140(1):95-107.
doi:10.1007/s10973-019-08846-w .

Obradović, Nina, Fahrenholtz, William G., Filipović, Suzana, Marković, Smilja, Blagojević, Vladimir A., Lević, Steva, Savić, Slobodan, Djordjević, Antonije, Pavlović, Vladimir, "Formation kinetics and cation inversion in mechanically activated MgAl2O4 spinel ceramics" in Journal of Thermal Analysis and Calorimetry, 140, no. 1 (2020):95-107,
https://doi.org/10.1007/s10973-019-08846-w . .

TY  - JOUR
AU  - Obradović, Nina
AU  - Pavlović, Vera P.
AU  - Kachlik, Martin
AU  - Maca, Karel
AU  - Olcan, Dragan
AU  - Djordjević, Antonije
AU  - Tshantshapanyan, Ani
AU  - Vlahović, Branislav
AU  - Pavlović, Vladimir
PY  - 2019
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/5098
AB  - Sintering of pure cordierite 2MgO:2Al(2)O(3):5SiO(2), and cordierite with the addition of 5 mass % TeO2 was studied. Green bodies were prepared from powder mixtures mechanically activated in a high-energy planetary mill, shaped by uniaxial (20 MPa) and cold isostatic pressing (1000 MPa). The pressure-less sintering of these specimens was performed at 1350 degrees C for 1 h. High relative density over 95% of the theoretical value was obtained through solid-state reaction and pressure-less sintering of powder activated for 40 min, and for the first time reported in the literature. Phase composition and microstructures of sintered samples were determined by XRD and SEM, coupled with EDS mapping. The real part of the complex relative permittivity of the samples was measured at 200 MHz. The loss tangent of all samples was below the resolution of the measurement setup. A strong correlation between the relative permittivity and the density agrees with previously published data.
PB  - Taylor & Francis Ltd, Abingdon
T2  - Advances in Applied Ceramics
T1  - Processing and properties of dense cordierite ceramics obtained through solid-state reaction and pressure-less sintering
EP  - 248
IS  - 5
SP  - 241
VL  - 118
DO  - 10.1080/17436753.2018.1548150
ER  - 

@article{
author = "Obradović, Nina and Pavlović, Vera P. and Kachlik, Martin and Maca, Karel and Olcan, Dragan and Djordjević, Antonije and Tshantshapanyan, Ani and Vlahović, Branislav and Pavlović, Vladimir",
year = "2019",
abstract = "Sintering of pure cordierite 2MgO:2Al(2)O(3):5SiO(2), and cordierite with the addition of 5 mass % TeO2 was studied. Green bodies were prepared from powder mixtures mechanically activated in a high-energy planetary mill, shaped by uniaxial (20 MPa) and cold isostatic pressing (1000 MPa). The pressure-less sintering of these specimens was performed at 1350 degrees C for 1 h. High relative density over 95% of the theoretical value was obtained through solid-state reaction and pressure-less sintering of powder activated for 40 min, and for the first time reported in the literature. Phase composition and microstructures of sintered samples were determined by XRD and SEM, coupled with EDS mapping. The real part of the complex relative permittivity of the samples was measured at 200 MHz. The loss tangent of all samples was below the resolution of the measurement setup. A strong correlation between the relative permittivity and the density agrees with previously published data.",
publisher = "Taylor & Francis Ltd, Abingdon",
journal = "Advances in Applied Ceramics",
title = "Processing and properties of dense cordierite ceramics obtained through solid-state reaction and pressure-less sintering",
pages = "248-241",
number = "5",
volume = "118",
doi = "10.1080/17436753.2018.1548150"
}

Obradović, N., Pavlović, V. P., Kachlik, M., Maca, K., Olcan, D., Djordjević, A., Tshantshapanyan, A., Vlahović, B.,& Pavlović, V.. (2019). Processing and properties of dense cordierite ceramics obtained through solid-state reaction and pressure-less sintering. in Advances in Applied Ceramics
Taylor & Francis Ltd, Abingdon., 118(5), 241-248.
https://doi.org/10.1080/17436753.2018.1548150

Obradović N, Pavlović VP, Kachlik M, Maca K, Olcan D, Djordjević A, Tshantshapanyan A, Vlahović B, Pavlović V. Processing and properties of dense cordierite ceramics obtained through solid-state reaction and pressure-less sintering. in Advances in Applied Ceramics. 2019;118(5):241-248.
doi:10.1080/17436753.2018.1548150 .

Obradović, Nina, Pavlović, Vera P., Kachlik, Martin, Maca, Karel, Olcan, Dragan, Djordjević, Antonije, Tshantshapanyan, Ani, Vlahović, Branislav, Pavlović, Vladimir, "Processing and properties of dense cordierite ceramics obtained through solid-state reaction and pressure-less sintering" in Advances in Applied Ceramics, 118, no. 5 (2019):241-248,
https://doi.org/10.1080/17436753.2018.1548150 . .

TY  - JOUR
AU  - Terzić, Anja
AU  - Obradović, Nina
AU  - Kosanović, Darko
AU  - Stojanović, Jovica
AU  - Djordjević, Antonije
AU  - Andrić, Ljubiša
AU  - Pavlović, Vladimir
PY  - 2019
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/5028
AB  - Steatite, as ceramic with composition predominantly resting on magnesium silicate, was produced from economic resources - talc, aluminosilicate clays, and either BaCO3 or feldspar as flux. Titanium dioxide was a doping agent. Four steatite mixtures were mechanically activated in a planetary ball mill for 30, 45 or 60 min, prior to the thermal treatment. Two-step sintering with initial phase set at 1350 degrees C and holding period conducted at 1250 degrees C was applied to initiate diffusion and prevent grain growth. Thereby, a high density ceramic material with low-porous submicron structure was acquired. The effects of TiO2 addition on densification, microstructure, and dielectric characteristics of steatites were monitored. The thermal stability of green mixtures was tested by differential thermal and thermogravimetric analyses. Changes in crystallinity and mineral phase composition were observed by the X-ray diffraction technique. Microstructural visualization with spatial arrangements of individual chemical elements on surface of the sintered ceramics was acquired by scanning electron microscopy accompanied with EDS mapping. In order to test the possibility of employment of the obtained steatites in insulation materials, electrical measurements were conducted by recording variations of the dielectric constant and loss tangent as a function of alternations in the mix-design and the mechanical activation period.
PB  - Elsevier Sci Ltd, Oxford
T2  - Ceramics International
T1  - Effects of mechanical-activation and TiO2 addition on the behavior of two-step sintered steatite ceramics
EP  - 3022
IS  - 3
SP  - 3013
VL  - 45
DO  - 10.1016/j.ceramint.2018.10.120
ER  - 

@article{
author = "Terzić, Anja and Obradović, Nina and Kosanović, Darko and Stojanović, Jovica and Djordjević, Antonije and Andrić, Ljubiša and Pavlović, Vladimir",
year = "2019",
abstract = "Steatite, as ceramic with composition predominantly resting on magnesium silicate, was produced from economic resources - talc, aluminosilicate clays, and either BaCO3 or feldspar as flux. Titanium dioxide was a doping agent. Four steatite mixtures were mechanically activated in a planetary ball mill for 30, 45 or 60 min, prior to the thermal treatment. Two-step sintering with initial phase set at 1350 degrees C and holding period conducted at 1250 degrees C was applied to initiate diffusion and prevent grain growth. Thereby, a high density ceramic material with low-porous submicron structure was acquired. The effects of TiO2 addition on densification, microstructure, and dielectric characteristics of steatites were monitored. The thermal stability of green mixtures was tested by differential thermal and thermogravimetric analyses. Changes in crystallinity and mineral phase composition were observed by the X-ray diffraction technique. Microstructural visualization with spatial arrangements of individual chemical elements on surface of the sintered ceramics was acquired by scanning electron microscopy accompanied with EDS mapping. In order to test the possibility of employment of the obtained steatites in insulation materials, electrical measurements were conducted by recording variations of the dielectric constant and loss tangent as a function of alternations in the mix-design and the mechanical activation period.",
publisher = "Elsevier Sci Ltd, Oxford",
journal = "Ceramics International",
title = "Effects of mechanical-activation and TiO2 addition on the behavior of two-step sintered steatite ceramics",
pages = "3022-3013",
number = "3",
volume = "45",
doi = "10.1016/j.ceramint.2018.10.120"
}

Terzić, A., Obradović, N., Kosanović, D., Stojanović, J., Djordjević, A., Andrić, L.,& Pavlović, V.. (2019). Effects of mechanical-activation and TiO2 addition on the behavior of two-step sintered steatite ceramics. in Ceramics International
Elsevier Sci Ltd, Oxford., 45(3), 3013-3022.
https://doi.org/10.1016/j.ceramint.2018.10.120

Terzić A, Obradović N, Kosanović D, Stojanović J, Djordjević A, Andrić L, Pavlović V. Effects of mechanical-activation and TiO2 addition on the behavior of two-step sintered steatite ceramics. in Ceramics International. 2019;45(3):3013-3022.
doi:10.1016/j.ceramint.2018.10.120 .

Terzić, Anja, Obradović, Nina, Kosanović, Darko, Stojanović, Jovica, Djordjević, Antonije, Andrić, Ljubiša, Pavlović, Vladimir, "Effects of mechanical-activation and TiO2 addition on the behavior of two-step sintered steatite ceramics" in Ceramics International, 45, no. 3 (2019):3013-3022,
https://doi.org/10.1016/j.ceramint.2018.10.120 . .

TY  - JOUR
AU  - Filipović, Suzana
AU  - Obradović, Nina
AU  - Marković, Smilja
AU  - Djordjević, Antonije
AU  - Balac, Igor
AU  - Dapcević, Aleksandra
AU  - Rogan, Jelena
AU  - Pavlović, Vladimir
PY  - 2018
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/4712
AB  - Corundum (alpha-alumina) is a suiTab. material for usage in various industry fields owing to its chemical stability, electrical and mechanical features. It is known that properties of ceramics could be modified by addition of different oxides, as well as by changing the consolidation parameters. In this respect, alumina was doped with 1 wt.% of Cr2O3, Mn2O3 and NiO, followed by 1 hour of mechanical activation in a high-energy planetary ball mill. A sensitive dilatometer was used for sintering of powder mixtures up to 1400 degrees C and recording the obtained dilatation. The final density varied between cca. 1.9 and 3.3 g/cm(3). Microstructural changes were detected by SEM measurements. Changes in electrical permittivity and loss tangent were associated with the preparation conditions (types of additives, duration of mechanical activation). For a given mixture, the sintering increases the relative permittivity and decreases losses, exhibiting the optimal values of 8.32 and 0.027, respectively, for the sample activated 60 minutes and sintered, with the addition of MnO2. Mechanical measurements indicate significant differences in strength with the addition of different transition metal oxides. Samples with Mn and Ni, activated and sintered, with strength of 121 and 86 MPa, respectively, have a significantly higher tensile strength than the other tested samples, due to their more compact microstructures.
PB  - Međunarodni Institut za nauku o sinterovanju, Beograd
T2  - Science of Sintering
T1  - Physical Properties of Sintered Alumina Doped with Different Oxides
EP  - 419
IS  - 4
SP  - 409
VL  - 50
DO  - 10.2298/SOS1804409F
ER  - 

@article{
author = "Filipović, Suzana and Obradović, Nina and Marković, Smilja and Djordjević, Antonije and Balac, Igor and Dapcević, Aleksandra and Rogan, Jelena and Pavlović, Vladimir",
year = "2018",
abstract = "Corundum (alpha-alumina) is a suiTab. material for usage in various industry fields owing to its chemical stability, electrical and mechanical features. It is known that properties of ceramics could be modified by addition of different oxides, as well as by changing the consolidation parameters. In this respect, alumina was doped with 1 wt.% of Cr2O3, Mn2O3 and NiO, followed by 1 hour of mechanical activation in a high-energy planetary ball mill. A sensitive dilatometer was used for sintering of powder mixtures up to 1400 degrees C and recording the obtained dilatation. The final density varied between cca. 1.9 and 3.3 g/cm(3). Microstructural changes were detected by SEM measurements. Changes in electrical permittivity and loss tangent were associated with the preparation conditions (types of additives, duration of mechanical activation). For a given mixture, the sintering increases the relative permittivity and decreases losses, exhibiting the optimal values of 8.32 and 0.027, respectively, for the sample activated 60 minutes and sintered, with the addition of MnO2. Mechanical measurements indicate significant differences in strength with the addition of different transition metal oxides. Samples with Mn and Ni, activated and sintered, with strength of 121 and 86 MPa, respectively, have a significantly higher tensile strength than the other tested samples, due to their more compact microstructures.",
publisher = "Međunarodni Institut za nauku o sinterovanju, Beograd",
journal = "Science of Sintering",
title = "Physical Properties of Sintered Alumina Doped with Different Oxides",
pages = "419-409",
number = "4",
volume = "50",
doi = "10.2298/SOS1804409F"
}

Filipović, S., Obradović, N., Marković, S., Djordjević, A., Balac, I., Dapcević, A., Rogan, J.,& Pavlović, V.. (2018). Physical Properties of Sintered Alumina Doped with Different Oxides. in Science of Sintering
Međunarodni Institut za nauku o sinterovanju, Beograd., 50(4), 409-419.
https://doi.org/10.2298/SOS1804409F

Filipović S, Obradović N, Marković S, Djordjević A, Balac I, Dapcević A, Rogan J, Pavlović V. Physical Properties of Sintered Alumina Doped with Different Oxides. in Science of Sintering. 2018;50(4):409-419.
doi:10.2298/SOS1804409F .

Filipović, Suzana, Obradović, Nina, Marković, Smilja, Djordjević, Antonije, Balac, Igor, Dapcević, Aleksandra, Rogan, Jelena, Pavlović, Vladimir, "Physical Properties of Sintered Alumina Doped with Different Oxides" in Science of Sintering, 50, no. 4 (2018):409-419,
https://doi.org/10.2298/SOS1804409F . .

TY  - JOUR
AU  - Djordjević, Antonije
AU  - Olcan, Dragan
AU  - Obradović, Nina
AU  - Paunović, Vesna
AU  - Filipović, Suzana
AU  - Pavlović, Vladimir
PY  - 2017
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/4433
AB  - Post-sintering of magnesium titanate ceramics by hot isostatic pressing (HIP) in an oxygen-free atmosphere significantly alters various electrical properties of the product. In particular, the sintered material becomes a semiconductor. The aims of this paper are: to extend our investigations of the electrical properties of this material by expanding the frequency range of measurements, to design interpolation formulas for the frequency dependence of the complex relative permittivity, and to propose HIP-sintered magnesium titanate as a material for thermistors that have a negative-temperature-coefficient resistance (NTCR), as well as for varistors.
PB  - Međunarodni Institut za nauku o sinterovanju, Beograd
T2  - Science of Sintering
T1  - Electrical Properties of Magnesium Titanate Ceramics Post-Sintered by Hot Isostatic Pressing
EP  - 380
IS  - 4
SP  - 373
VL  - 49
DO  - 10.2298/SOS1704373D
ER  - 

@article{
author = "Djordjević, Antonije and Olcan, Dragan and Obradović, Nina and Paunović, Vesna and Filipović, Suzana and Pavlović, Vladimir",
year = "2017",
abstract = "Post-sintering of magnesium titanate ceramics by hot isostatic pressing (HIP) in an oxygen-free atmosphere significantly alters various electrical properties of the product. In particular, the sintered material becomes a semiconductor. The aims of this paper are: to extend our investigations of the electrical properties of this material by expanding the frequency range of measurements, to design interpolation formulas for the frequency dependence of the complex relative permittivity, and to propose HIP-sintered magnesium titanate as a material for thermistors that have a negative-temperature-coefficient resistance (NTCR), as well as for varistors.",
publisher = "Međunarodni Institut za nauku o sinterovanju, Beograd",
journal = "Science of Sintering",
title = "Electrical Properties of Magnesium Titanate Ceramics Post-Sintered by Hot Isostatic Pressing",
pages = "380-373",
number = "4",
volume = "49",
doi = "10.2298/SOS1704373D"
}

Djordjević, A., Olcan, D., Obradović, N., Paunović, V., Filipović, S.,& Pavlović, V.. (2017). Electrical Properties of Magnesium Titanate Ceramics Post-Sintered by Hot Isostatic Pressing. in Science of Sintering
Međunarodni Institut za nauku o sinterovanju, Beograd., 49(4), 373-380.
https://doi.org/10.2298/SOS1704373D

Djordjević A, Olcan D, Obradović N, Paunović V, Filipović S, Pavlović V. Electrical Properties of Magnesium Titanate Ceramics Post-Sintered by Hot Isostatic Pressing. in Science of Sintering. 2017;49(4):373-380.
doi:10.2298/SOS1704373D .

Djordjević, Antonije, Olcan, Dragan, Obradović, Nina, Paunović, Vesna, Filipović, Suzana, Pavlović, Vladimir, "Electrical Properties of Magnesium Titanate Ceramics Post-Sintered by Hot Isostatic Pressing" in Science of Sintering, 49, no. 4 (2017):373-380,
https://doi.org/10.2298/SOS1704373D . .

TY  - JOUR
AU  - Terzić, Anja
AU  - Obradović, Nina
AU  - Stojanović, Jovica
AU  - Pavlović, Vladimir
AU  - Andrić, Ljubiša
AU  - Olcan, Dragan
AU  - Djordjević, Antonije
PY  - 2017
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/4491
AB  - The focus of the study was on providing insights into interconnections between sintering and development of the crystalline microstructure, and consequently variations in dielectric behavior of four steatites fabricated from a low-cost raw material, i.e. talc. The changes, induced by the alternations of the binders (bentonite, kaolin clay) and fluxing agents (BaCO3, feldspar), were monitored in the temperature range 1000 degrees to 1250 degrees C in which complete densification and re-crystallization of the investigated structures were accomplished. The critical points in the synthesis of steatite materials were assessed by instrumental analyses. Crystallinity changes and mineral phase transition during sintering were monitored by X-ray diffraction technique. Microstructural visualization of the samples and the spatial arrangements of individual chemical elements were achieved via scanning electron microscopy accompanied with EDS mapping. The thermal stability was observed on the green mixtures using differential thermal and thermo gravimetric analyses. Electrical measurements recorded variations of the dielectric constant (epsilon(r)) and loss tangent (tan delta) as a function of the sintering temperature. The investigation highlighted critical design points, as well as the optimal combinations of the raw materials for production of the steatite ceramics for advanced electrical engineering applications.
PB  - Elsevier Sci Ltd, Oxford
T2  - Ceramics International
T1  - Influence of different bonding and fluxing agents on the sintering behavior and dielectric properties of steatite ceramic materials
EP  - 13275
IS  - 16
SP  - 13264
VL  - 43
DO  - 10.1016/j.ceramint.2017.07.024
ER  - 

@article{
author = "Terzić, Anja and Obradović, Nina and Stojanović, Jovica and Pavlović, Vladimir and Andrić, Ljubiša and Olcan, Dragan and Djordjević, Antonije",
year = "2017",
abstract = "The focus of the study was on providing insights into interconnections between sintering and development of the crystalline microstructure, and consequently variations in dielectric behavior of four steatites fabricated from a low-cost raw material, i.e. talc. The changes, induced by the alternations of the binders (bentonite, kaolin clay) and fluxing agents (BaCO3, feldspar), were monitored in the temperature range 1000 degrees to 1250 degrees C in which complete densification and re-crystallization of the investigated structures were accomplished. The critical points in the synthesis of steatite materials were assessed by instrumental analyses. Crystallinity changes and mineral phase transition during sintering were monitored by X-ray diffraction technique. Microstructural visualization of the samples and the spatial arrangements of individual chemical elements were achieved via scanning electron microscopy accompanied with EDS mapping. The thermal stability was observed on the green mixtures using differential thermal and thermo gravimetric analyses. Electrical measurements recorded variations of the dielectric constant (epsilon(r)) and loss tangent (tan delta) as a function of the sintering temperature. The investigation highlighted critical design points, as well as the optimal combinations of the raw materials for production of the steatite ceramics for advanced electrical engineering applications.",
publisher = "Elsevier Sci Ltd, Oxford",
journal = "Ceramics International",
title = "Influence of different bonding and fluxing agents on the sintering behavior and dielectric properties of steatite ceramic materials",
pages = "13275-13264",
number = "16",
volume = "43",
doi = "10.1016/j.ceramint.2017.07.024"
}

Terzić, A., Obradović, N., Stojanović, J., Pavlović, V., Andrić, L., Olcan, D.,& Djordjević, A.. (2017). Influence of different bonding and fluxing agents on the sintering behavior and dielectric properties of steatite ceramic materials. in Ceramics International
Elsevier Sci Ltd, Oxford., 43(16), 13264-13275.
https://doi.org/10.1016/j.ceramint.2017.07.024

Terzić A, Obradović N, Stojanović J, Pavlović V, Andrić L, Olcan D, Djordjević A. Influence of different bonding and fluxing agents on the sintering behavior and dielectric properties of steatite ceramic materials. in Ceramics International. 2017;43(16):13264-13275.
doi:10.1016/j.ceramint.2017.07.024 .

Terzić, Anja, Obradović, Nina, Stojanović, Jovica, Pavlović, Vladimir, Andrić, Ljubiša, Olcan, Dragan, Djordjević, Antonije, "Influence of different bonding and fluxing agents on the sintering behavior and dielectric properties of steatite ceramic materials" in Ceramics International, 43, no. 16 (2017):13264-13275,
https://doi.org/10.1016/j.ceramint.2017.07.024 . .

TY  - JOUR
AU  - Filipović, Suzana
AU  - Obradović, N.
AU  - Pavlović, Vladimir
AU  - Mitrić, M.
AU  - Djordjević, Antonije
AU  - Kachlik, Martin
AU  - Maca, Karel
PY  - 2016
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/4209
AB  - The aim of this study is to explore the influence of the processing route on the structural and physical properties of bulk MgTiO3 ceramics. Commercially available MgO and TiO2 powders were mechanically activated in a planetary ball mill. Green bodies were formed by an isostatic pressure of 300 MPa. The sintering of these samples was done either by the Two-Step Sintering (TSS) approach or by conventional pressureless sintering followed by Hot Isostatic Pressing (post-HIPing). The first set of compacts was sintered by TSS in air at 1300 degrees C for 30 min and the next step was performed at 1200 degrees C for 20 h. The density of the obtained samples after the two-step sintering reached almost 90% of the theoretical density (%TD). The second set of compacts was sintered at 1400 degrees C for 30 min in air. The samples without open porosity were post-sintered by the HIP at 1200 degrees C for 2 h in an argon atmosphere at a pressure of 200 MPa. The density significantly increased up to 96%TD. The differences between samples prepared by these two techniques were also analyzed by XRD and SEM. The lattice vibration spectra were obtained using Raman spectroscopy and they indicate a high degree of lattice disorder, as well as high values of the oxygen vacancy concentration. Electrical characteristic were established in the frequency range from 10 kHz to 10 GHz. The choice of the processing route had considerable influence on structural and physical properties of MgTiO3 ceramics.
PB  - Elsevier Sci Ltd, Oxford
T2  - Ceramics International
T1  - Effect of consolidation parameters on structural, microstructural and electrical properties of magnesium titanate ceramics
EP  - 9898
IS  - 8
SP  - 9887
VL  - 42
DO  - 10.1016/j.ceramint.2016.03.088
ER  - 

@article{
author = "Filipović, Suzana and Obradović, N. and Pavlović, Vladimir and Mitrić, M. and Djordjević, Antonije and Kachlik, Martin and Maca, Karel",
year = "2016",
abstract = "The aim of this study is to explore the influence of the processing route on the structural and physical properties of bulk MgTiO3 ceramics. Commercially available MgO and TiO2 powders were mechanically activated in a planetary ball mill. Green bodies were formed by an isostatic pressure of 300 MPa. The sintering of these samples was done either by the Two-Step Sintering (TSS) approach or by conventional pressureless sintering followed by Hot Isostatic Pressing (post-HIPing). The first set of compacts was sintered by TSS in air at 1300 degrees C for 30 min and the next step was performed at 1200 degrees C for 20 h. The density of the obtained samples after the two-step sintering reached almost 90% of the theoretical density (%TD). The second set of compacts was sintered at 1400 degrees C for 30 min in air. The samples without open porosity were post-sintered by the HIP at 1200 degrees C for 2 h in an argon atmosphere at a pressure of 200 MPa. The density significantly increased up to 96%TD. The differences between samples prepared by these two techniques were also analyzed by XRD and SEM. The lattice vibration spectra were obtained using Raman spectroscopy and they indicate a high degree of lattice disorder, as well as high values of the oxygen vacancy concentration. Electrical characteristic were established in the frequency range from 10 kHz to 10 GHz. The choice of the processing route had considerable influence on structural and physical properties of MgTiO3 ceramics.",
publisher = "Elsevier Sci Ltd, Oxford",
journal = "Ceramics International",
title = "Effect of consolidation parameters on structural, microstructural and electrical properties of magnesium titanate ceramics",
pages = "9898-9887",
number = "8",
volume = "42",
doi = "10.1016/j.ceramint.2016.03.088"
}

Filipović, S., Obradović, N., Pavlović, V., Mitrić, M., Djordjević, A., Kachlik, M.,& Maca, K.. (2016). Effect of consolidation parameters on structural, microstructural and electrical properties of magnesium titanate ceramics. in Ceramics International
Elsevier Sci Ltd, Oxford., 42(8), 9887-9898.
https://doi.org/10.1016/j.ceramint.2016.03.088

Filipović S, Obradović N, Pavlović V, Mitrić M, Djordjević A, Kachlik M, Maca K. Effect of consolidation parameters on structural, microstructural and electrical properties of magnesium titanate ceramics. in Ceramics International. 2016;42(8):9887-9898.
doi:10.1016/j.ceramint.2016.03.088 .

Filipović, Suzana, Obradović, N., Pavlović, Vladimir, Mitrić, M., Djordjević, Antonije, Kachlik, Martin, Maca, Karel, "Effect of consolidation parameters on structural, microstructural and electrical properties of magnesium titanate ceramics" in Ceramics International, 42, no. 8 (2016):9887-9898,
https://doi.org/10.1016/j.ceramint.2016.03.088 . .

TY  - JOUR
AU  - Obradović, Nina
AU  - Filipović, Suzana
AU  - Djordjević, Nataša
AU  - Kosanović, Darko
AU  - Marković, Smilja
AU  - Pavlović, Vladimir
AU  - Olcan, Dragan
AU  - Djordjević, Antonije
AU  - Kachlik, Martin
AU  - Maca, Karel
PY  - 2016
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/4019
AB  - The mechanical activation can help reduce production costs and modify cordierite-based materials. In this study, the structure and electrical properties of the mechanically activated MgO-Al2O3-SiO2 system have been analyzed. The mixtures of MgO-Al2O3-SiO2 powders were mechanically activated in a planetary ball mill for time periods ranging from 0 to 160 min. Structural investigations were performed on the obtained powders. The effects of activation and a two-step sintering process on the microstructure and crystal structure were investigated by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The thermal stability was analyzed using DTA. Electrical measurements showed variations of the dielectric constant (epsilon(r)) and loss tangent (tan delta) as a function of the time of mechanical treatment.
PB  - Elsevier Sci Ltd, Oxford
T2  - Ceramics International
T1  - Effects of mechanical activation and two-step sintering on the structure and electrical properties of cordierite-based ceramics
EP  - 13918
IS  - 12
SP  - 13909
VL  - 42
DO  - 10.1016/j.ceramint.2016.05.201
ER  - 

@article{
author = "Obradović, Nina and Filipović, Suzana and Djordjević, Nataša and Kosanović, Darko and Marković, Smilja and Pavlović, Vladimir and Olcan, Dragan and Djordjević, Antonije and Kachlik, Martin and Maca, Karel",
year = "2016",
abstract = "The mechanical activation can help reduce production costs and modify cordierite-based materials. In this study, the structure and electrical properties of the mechanically activated MgO-Al2O3-SiO2 system have been analyzed. The mixtures of MgO-Al2O3-SiO2 powders were mechanically activated in a planetary ball mill for time periods ranging from 0 to 160 min. Structural investigations were performed on the obtained powders. The effects of activation and a two-step sintering process on the microstructure and crystal structure were investigated by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The thermal stability was analyzed using DTA. Electrical measurements showed variations of the dielectric constant (epsilon(r)) and loss tangent (tan delta) as a function of the time of mechanical treatment.",
publisher = "Elsevier Sci Ltd, Oxford",
journal = "Ceramics International",
title = "Effects of mechanical activation and two-step sintering on the structure and electrical properties of cordierite-based ceramics",
pages = "13918-13909",
number = "12",
volume = "42",
doi = "10.1016/j.ceramint.2016.05.201"
}

Obradović, N., Filipović, S., Djordjević, N., Kosanović, D., Marković, S., Pavlović, V., Olcan, D., Djordjević, A., Kachlik, M.,& Maca, K.. (2016). Effects of mechanical activation and two-step sintering on the structure and electrical properties of cordierite-based ceramics. in Ceramics International
Elsevier Sci Ltd, Oxford., 42(12), 13909-13918.
https://doi.org/10.1016/j.ceramint.2016.05.201

Obradović N, Filipović S, Djordjević N, Kosanović D, Marković S, Pavlović V, Olcan D, Djordjević A, Kachlik M, Maca K. Effects of mechanical activation and two-step sintering on the structure and electrical properties of cordierite-based ceramics. in Ceramics International. 2016;42(12):13909-13918.
doi:10.1016/j.ceramint.2016.05.201 .

Obradović, Nina, Filipović, Suzana, Djordjević, Nataša, Kosanović, Darko, Marković, Smilja, Pavlović, Vladimir, Olcan, Dragan, Djordjević, Antonije, Kachlik, Martin, Maca, Karel, "Effects of mechanical activation and two-step sintering on the structure and electrical properties of cordierite-based ceramics" in Ceramics International, 42, no. 12 (2016):13909-13918,
https://doi.org/10.1016/j.ceramint.2016.05.201 . .

TY  - JOUR
AU  - Obradović, Nina
AU  - Filipović, Suzana
AU  - Djordjević, Nataša
AU  - Kosanović, Darko
AU  - Pavlović, Vladimir
AU  - Olcan, Dragan
AU  - Djordjević, Antonije
AU  - Kachlik, Martin
AU  - Maca, Karel
PY  - 2016
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/4026
AB  - Cordierite-based ceramic materials are attracting much interest for their various applications in industry, for manufacturing multilayer circuit boards, catalytic converters, filters, thermal insulation, kiln furniture, components of portable electronic devices, etc. In order to reduce production costs and modify cordierite-based materials, mechanical activation can be used. In this study, microstructural and electrical properties of mechanically activated MgO-Al2O3-SiO2 system have been analyzed. The mixtures of MgO-Al2O3-SiO2 powders were mechanically activated in a planetary ball mill for the time periods from 0 to 160 min. Morphological investigations have been performed on the obtained powders. The effects of activation and two-step sintering process on microstructure were investigated by scanning electron microscopy (SEM). Electrical measurements showed variations of the dielectric constant (epsilon(r)) and loss tangent (tan delta) as a function of time of mechanical treatment.
PB  - Međunarodni Institut za nauku o sinterovanju, Beograd
T2  - Science of Sintering
T1  - Microstructural and Electrical Properties of Cordierite-based Ceramics Obtained After Two-step Sintering Technique
EP  - 165
IS  - 2
SP  - 157
VL  - 48
DO  - 10.2298/SOS1602157O
ER  - 

@article{
author = "Obradović, Nina and Filipović, Suzana and Djordjević, Nataša and Kosanović, Darko and Pavlović, Vladimir and Olcan, Dragan and Djordjević, Antonije and Kachlik, Martin and Maca, Karel",
year = "2016",
abstract = "Cordierite-based ceramic materials are attracting much interest for their various applications in industry, for manufacturing multilayer circuit boards, catalytic converters, filters, thermal insulation, kiln furniture, components of portable electronic devices, etc. In order to reduce production costs and modify cordierite-based materials, mechanical activation can be used. In this study, microstructural and electrical properties of mechanically activated MgO-Al2O3-SiO2 system have been analyzed. The mixtures of MgO-Al2O3-SiO2 powders were mechanically activated in a planetary ball mill for the time periods from 0 to 160 min. Morphological investigations have been performed on the obtained powders. The effects of activation and two-step sintering process on microstructure were investigated by scanning electron microscopy (SEM). Electrical measurements showed variations of the dielectric constant (epsilon(r)) and loss tangent (tan delta) as a function of time of mechanical treatment.",
publisher = "Međunarodni Institut za nauku o sinterovanju, Beograd",
journal = "Science of Sintering",
title = "Microstructural and Electrical Properties of Cordierite-based Ceramics Obtained After Two-step Sintering Technique",
pages = "165-157",
number = "2",
volume = "48",
doi = "10.2298/SOS1602157O"
}

Obradović, N., Filipović, S., Djordjević, N., Kosanović, D., Pavlović, V., Olcan, D., Djordjević, A., Kachlik, M.,& Maca, K.. (2016). Microstructural and Electrical Properties of Cordierite-based Ceramics Obtained After Two-step Sintering Technique. in Science of Sintering
Međunarodni Institut za nauku o sinterovanju, Beograd., 48(2), 157-165.
https://doi.org/10.2298/SOS1602157O

Obradović N, Filipović S, Djordjević N, Kosanović D, Pavlović V, Olcan D, Djordjević A, Kachlik M, Maca K. Microstructural and Electrical Properties of Cordierite-based Ceramics Obtained After Two-step Sintering Technique. in Science of Sintering. 2016;48(2):157-165.
doi:10.2298/SOS1602157O .

Obradović, Nina, Filipović, Suzana, Djordjević, Nataša, Kosanović, Darko, Pavlović, Vladimir, Olcan, Dragan, Djordjević, Antonije, Kachlik, Martin, Maca, Karel, "Microstructural and Electrical Properties of Cordierite-based Ceramics Obtained After Two-step Sintering Technique" in Science of Sintering, 48, no. 2 (2016):157-165,
https://doi.org/10.2298/SOS1602157O . .

TY  - JOUR
AU  - Obradović, N.
AU  - Nikolić, M.V.
AU  - Nikolić, N.
AU  - Filipović, Suzana
AU  - Mitrić, M.
AU  - Pavlović, Vladimir
AU  - Nikolić, P.M.
AU  - Djordjević, Antonije
AU  - Ristić, M.M.
PY  - 2012
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/3052
AB  - Mixtures of BaCO3, ZnO and TiO2 powders, with molar ratio of 1:2:4, were mechanically activated for 20, 40 and minutes in a planetary ball mill. The resulting powders were compacted into pellets and isothermally sintered at 1250 degrees C for 2h with a heating rate of 10 degrees C/min. X-ray diffraction analysis of obtained powders and sintered samples was performed in order to investigate changes of the phase composition. The microstructure of sintered samples was examined by scanning electron microscopy. The photoacoustic phase and amplitude spectra of sintered samples were measured as a function of the laser beam modulating frequency using a transmission detection configuration. Fitting of experimental data enabled determination of photoacoustic properties including thermal diffusivity. Based on the results obtained correlation between thermal diffusivity and experimental conditions, as well the samples microstructure characteristics, was discussed.
PB  - Međunarodni Institut za nauku o sinterovanju, Beograd
T2  - Science of Sintering
T1  - Synthesis of Barium-zinc-titanate Ceramics
EP  - 71
IS  - 1
SP  - 65
VL  - 44
DO  - 10.2298/SOS1201065O
ER  - 

@article{
author = "Obradović, N. and Nikolić, M.V. and Nikolić, N. and Filipović, Suzana and Mitrić, M. and Pavlović, Vladimir and Nikolić, P.M. and Djordjević, Antonije and Ristić, M.M.",
year = "2012",
abstract = "Mixtures of BaCO3, ZnO and TiO2 powders, with molar ratio of 1:2:4, were mechanically activated for 20, 40 and minutes in a planetary ball mill. The resulting powders were compacted into pellets and isothermally sintered at 1250 degrees C for 2h with a heating rate of 10 degrees C/min. X-ray diffraction analysis of obtained powders and sintered samples was performed in order to investigate changes of the phase composition. The microstructure of sintered samples was examined by scanning electron microscopy. The photoacoustic phase and amplitude spectra of sintered samples were measured as a function of the laser beam modulating frequency using a transmission detection configuration. Fitting of experimental data enabled determination of photoacoustic properties including thermal diffusivity. Based on the results obtained correlation between thermal diffusivity and experimental conditions, as well the samples microstructure characteristics, was discussed.",
publisher = "Međunarodni Institut za nauku o sinterovanju, Beograd",
journal = "Science of Sintering",
title = "Synthesis of Barium-zinc-titanate Ceramics",
pages = "71-65",
number = "1",
volume = "44",
doi = "10.2298/SOS1201065O"
}

Obradović, N., Nikolić, M.V., Nikolić, N., Filipović, S., Mitrić, M., Pavlović, V., Nikolić, P.M., Djordjević, A.,& Ristić, M.M.. (2012). Synthesis of Barium-zinc-titanate Ceramics. in Science of Sintering
Međunarodni Institut za nauku o sinterovanju, Beograd., 44(1), 65-71.
https://doi.org/10.2298/SOS1201065O

Obradović N, Nikolić M, Nikolić N, Filipović S, Mitrić M, Pavlović V, Nikolić P, Djordjević A, Ristić M. Synthesis of Barium-zinc-titanate Ceramics. in Science of Sintering. 2012;44(1):65-71.
doi:10.2298/SOS1201065O .

Obradović, N., Nikolić, M.V., Nikolić, N., Filipović, Suzana, Mitrić, M., Pavlović, Vladimir, Nikolić, P.M., Djordjević, Antonije, Ristić, M.M., "Synthesis of Barium-zinc-titanate Ceramics" in Science of Sintering, 44, no. 1 (2012):65-71,
https://doi.org/10.2298/SOS1201065O . .