TY  - JOUR
AU  - Filipović, Suzana
AU  - Obradović, Nina
AU  - Fahrenholtz, William G.
AU  - Smith, Steven
AU  - Mirković, Miljana M.
AU  - Peleš Tadić, Adriana
AU  - Petrović, Jovana
AU  - Đorđević, Antonije
PY  - 2024
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/12795
AB  - Magnesium titanate ceramics were prepared by reactive spark plasma sintering (SPS) at 1200 °C for 5 min. Prior to sintering, MgO and TiO2 powders were mixed by high energy ball milling (HEBM) for 15, 30, or 60 min. The effect of milling time on phase composition was analyzed by X-ray diffraction (XRD) for milled powders and sintered specimens. The morphology of the sintered ceramics was investigated by scanning electron microscopy (SEM), while elemental distribution was determined by energy dispersive spectroscopy (EDS). The presence of the MgTi2O5 phase was detected in XRD and was confirmed by EDS analysis. Microcracking was observed for specimens prepared with longer milling times and attributed to the coefficient of thermal expansion (CTE) mismatch dominantly due to the anisotropic crystal structure of MgTiO3 phase. The sample milled for 15 min showed the highest Vickers hardness due to less or no microcracking and nearly full density. The dielectric measurements in the range of 10 Hz–250 MHz demonstrated extremely high dielectric permittivity, as high as 104 at 1 kHz. An increase in loss tangents was observed due to oxygen vacancy formation, which was promoted by the vacuum environment during SPS. Oxygen vacancy-related dielectric relaxation was also detected and explained.
T2  - Ceramics International
T1  - Spark plasma sintering of magnesium titanate ceramics
IS  - InPress
DO  - 10.1016/j.ceramint.2024.02.004
ER  - 

@article{
author = "Filipović, Suzana and Obradović, Nina and Fahrenholtz, William G. and Smith, Steven and Mirković, Miljana M. and Peleš Tadić, Adriana and Petrović, Jovana and Đorđević, Antonije",
year = "2024",
abstract = "Magnesium titanate ceramics were prepared by reactive spark plasma sintering (SPS) at 1200 °C for 5 min. Prior to sintering, MgO and TiO2 powders were mixed by high energy ball milling (HEBM) for 15, 30, or 60 min. The effect of milling time on phase composition was analyzed by X-ray diffraction (XRD) for milled powders and sintered specimens. The morphology of the sintered ceramics was investigated by scanning electron microscopy (SEM), while elemental distribution was determined by energy dispersive spectroscopy (EDS). The presence of the MgTi2O5 phase was detected in XRD and was confirmed by EDS analysis. Microcracking was observed for specimens prepared with longer milling times and attributed to the coefficient of thermal expansion (CTE) mismatch dominantly due to the anisotropic crystal structure of MgTiO3 phase. The sample milled for 15 min showed the highest Vickers hardness due to less or no microcracking and nearly full density. The dielectric measurements in the range of 10 Hz–250 MHz demonstrated extremely high dielectric permittivity, as high as 104 at 1 kHz. An increase in loss tangents was observed due to oxygen vacancy formation, which was promoted by the vacuum environment during SPS. Oxygen vacancy-related dielectric relaxation was also detected and explained.",
journal = "Ceramics International",
title = "Spark plasma sintering of magnesium titanate ceramics",
number = "InPress",
doi = "10.1016/j.ceramint.2024.02.004"
}

Filipović, S., Obradović, N., Fahrenholtz, W. G., Smith, S., Mirković, M. M., Peleš Tadić, A., Petrović, J.,& Đorđević, A.. (2024). Spark plasma sintering of magnesium titanate ceramics. in Ceramics International(InPress).
https://doi.org/10.1016/j.ceramint.2024.02.004

Filipović S, Obradović N, Fahrenholtz WG, Smith S, Mirković MM, Peleš Tadić A, Petrović J, Đorđević A. Spark plasma sintering of magnesium titanate ceramics. in Ceramics International. 2024;(InPress).
doi:10.1016/j.ceramint.2024.02.004 .

Filipović, Suzana, Obradović, Nina, Fahrenholtz, William G., Smith, Steven, Mirković, Miljana M., Peleš Tadić, Adriana, Petrović, Jovana, Đorđević, Antonije, "Spark plasma sintering of magnesium titanate ceramics" in Ceramics International, no. InPress (2024),
https://doi.org/10.1016/j.ceramint.2024.02.004 . .

TY  - CONF
AU  - Filipović, Suzana
AU  - Obradović, Nina
AU  - Fahrenholtz, William G.
AU  - Smith, Steven
AU  - Mirković, M.
AU  - Peleš, Adriana
AU  - Tadić, Nenad
AU  - Đorđević, Antonije
PY  - 2022
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/10825
AB  - Perovskite ceramic material based on MgTiO3 is used in various types of electronic devices owing to its dielectric properties, high dielectric constant, and low losses. These features can be tailored by setting preparation conditions. Densification of magnesium titanate by Spark Plasma Sintering (SPS) was the aim of this work. First, the mechanical activation in the highenergy ball mill was applied on the powder of MgO-TiO2 mixed in mole ratio 1:1. Prepared powder mixtures, activated for different times, were SPS sintered, at 1200 o C with a heating rate of 100o C/min. After reaching the desired temperature, a uniaxial pressure of 50 MPa was applied, and dwelled at this condition for 5 min, followed by cooling to room temperature at 5o C/min. The starting powders, activated mixtures, and sintered ceramics bodies were investigated by X-ray diffraction, scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS). The presence of the MgTi2O5 phase was noticed for the nonmilled ceramics. In the samples obtained from milled powders, MgTi2O5 was detected in EDS spectra in a lower amount, below the threshold of the XRD method. Dielectric measurements were performed at a wide range of frequencies and temperatures. The highest value of the hardness was obtained from powder milled for 15 min before SPS.
PB  - Belgrade : Serbian Ceramic Society
C3  - Advanced Ceramics and Application : 10th Serbian Ceramic Society Conference : program and the book of abstracts; September 26-27, 2022; Belgrade
T1  - Effect of high energy ball milling on sintering of MgO-TiO2 system
SP  - 88
UR  - https://hdl.handle.net/21.15107/rcub_vinar_10825
ER  - 

@conference{
author = "Filipović, Suzana and Obradović, Nina and Fahrenholtz, William G. and Smith, Steven and Mirković, M. and Peleš, Adriana and Tadić, Nenad and Đorđević, Antonije",
year = "2022",
abstract = "Perovskite ceramic material based on MgTiO3 is used in various types of electronic devices owing to its dielectric properties, high dielectric constant, and low losses. These features can be tailored by setting preparation conditions. Densification of magnesium titanate by Spark Plasma Sintering (SPS) was the aim of this work. First, the mechanical activation in the highenergy ball mill was applied on the powder of MgO-TiO2 mixed in mole ratio 1:1. Prepared powder mixtures, activated for different times, were SPS sintered, at 1200 o C with a heating rate of 100o C/min. After reaching the desired temperature, a uniaxial pressure of 50 MPa was applied, and dwelled at this condition for 5 min, followed by cooling to room temperature at 5o C/min. The starting powders, activated mixtures, and sintered ceramics bodies were investigated by X-ray diffraction, scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS). The presence of the MgTi2O5 phase was noticed for the nonmilled ceramics. In the samples obtained from milled powders, MgTi2O5 was detected in EDS spectra in a lower amount, below the threshold of the XRD method. Dielectric measurements were performed at a wide range of frequencies and temperatures. The highest value of the hardness was obtained from powder milled for 15 min before SPS.",
publisher = "Belgrade : Serbian Ceramic Society",
journal = "Advanced Ceramics and Application : 10th Serbian Ceramic Society Conference : program and the book of abstracts; September 26-27, 2022; Belgrade",
title = "Effect of high energy ball milling on sintering of MgO-TiO2 system",
pages = "88",
url = "https://hdl.handle.net/21.15107/rcub_vinar_10825"
}

Filipović, S., Obradović, N., Fahrenholtz, W. G., Smith, S., Mirković, M., Peleš, A., Tadić, N.,& Đorđević, A.. (2022). Effect of high energy ball milling on sintering of MgO-TiO2 system. in Advanced Ceramics and Application : 10th Serbian Ceramic Society Conference : program and the book of abstracts; September 26-27, 2022; Belgrade
Belgrade : Serbian Ceramic Society., 88.
https://hdl.handle.net/21.15107/rcub_vinar_10825

Filipović S, Obradović N, Fahrenholtz WG, Smith S, Mirković M, Peleš A, Tadić N, Đorđević A. Effect of high energy ball milling on sintering of MgO-TiO2 system. in Advanced Ceramics and Application : 10th Serbian Ceramic Society Conference : program and the book of abstracts; September 26-27, 2022; Belgrade. 2022;:88.
https://hdl.handle.net/21.15107/rcub_vinar_10825 .

Filipović, Suzana, Obradović, Nina, Fahrenholtz, William G., Smith, Steven, Mirković, M., Peleš, Adriana, Tadić, Nenad, Đorđević, Antonije, "Effect of high energy ball milling on sintering of MgO-TiO2 system" in Advanced Ceramics and Application : 10th Serbian Ceramic Society Conference : program and the book of abstracts; September 26-27, 2022; Belgrade (2022):88,
https://hdl.handle.net/21.15107/rcub_vinar_10825 .