TY  - JOUR
AU  - Stanfield, Austin D.
AU  - Smith, Steven M.
AU  - Filipović, Suzana
AU  - Obradović, Nina
AU  - Buljak, Vladimir
AU  - Hilmas, Gregory E.
AU  - Fahrenholtz, William G.
PY  - 2023
UR  - https://dais.sanu.ac.rs/123456789/15143
AB  - Final-stage sintering was analyzed for nominally phase pure zirconium diboride synthesized by borothermal reduction of high-purity ZrO2. Analysis was conducted on ZrB2 ceramics with relative densities greater than 90% using the Nabarro–Herring stress–directed vacancy diffusion model. Temperatures of 1900°C or above and an applied uniaxial pressure of 50 MPa were required to fully densify ZrB2 ceramics by direct current sintering. Ram travel data were collected and used to determine the relative density of the specimens during sintering. Specimens sintered between 1900 and 2100°C achieved relative densities greater than 97%, whereas specimens sintered below 1900°C failed to reach the final stage of sintering. The average grain size ranged from 1.0 to 14.7 μm. The activation energy was calculated from the slope of an Arrhenius plot that used the Kalish equation. The activation energy was 162 ± 34 kJ/mol, which is consistent with the activation energy for dislocation movement in ZrB2. The diffusion coefficients for dislocation motion that controls densification were 5.1 × 10−6 cm2/s at 1900°C and 5.1 × 10−5 cm2/s at 2100°C, as calculated from activation energy and average grain sizes. This study provides evidence that the dominant mechanism for final-stage sintering of ZrB2 ceramics is dislocation motion.
PB  - Wiley
T2  - Journal of the American Ceramic Society
T1  - Final‐stage densification kinetics of direct current–sintered ZrB2
SP  - 5654
EP  - 5661
VL  - 106
IS  - 10
DO  - 10.1111/jace.19212
UR  - https://hdl.handle.net/21.15107/rcub_dais_15143
ER  - 

@article{
author = "Stanfield, Austin D. and Smith, Steven M. and Filipović, Suzana and Obradović, Nina and Buljak, Vladimir and Hilmas, Gregory E. and Fahrenholtz, William G.",
year = "2023",
abstract = "Final-stage sintering was analyzed for nominally phase pure zirconium diboride synthesized by borothermal reduction of high-purity ZrO2. Analysis was conducted on ZrB2 ceramics with relative densities greater than 90% using the Nabarro–Herring stress–directed vacancy diffusion model. Temperatures of 1900°C or above and an applied uniaxial pressure of 50 MPa were required to fully densify ZrB2 ceramics by direct current sintering. Ram travel data were collected and used to determine the relative density of the specimens during sintering. Specimens sintered between 1900 and 2100°C achieved relative densities greater than 97%, whereas specimens sintered below 1900°C failed to reach the final stage of sintering. The average grain size ranged from 1.0 to 14.7 μm. The activation energy was calculated from the slope of an Arrhenius plot that used the Kalish equation. The activation energy was 162 ± 34 kJ/mol, which is consistent with the activation energy for dislocation movement in ZrB2. The diffusion coefficients for dislocation motion that controls densification were 5.1 × 10−6 cm2/s at 1900°C and 5.1 × 10−5 cm2/s at 2100°C, as calculated from activation energy and average grain sizes. This study provides evidence that the dominant mechanism for final-stage sintering of ZrB2 ceramics is dislocation motion.",
publisher = "Wiley",
journal = "Journal of the American Ceramic Society",
title = "Final‐stage densification kinetics of direct current–sintered ZrB2",
pages = "5654-5661",
volume = "106",
number = "10",
doi = "10.1111/jace.19212",
url = "https://hdl.handle.net/21.15107/rcub_dais_15143"
}

Stanfield, A. D., Smith, S. M., Filipović, S., Obradović, N., Buljak, V., Hilmas, G. E.,& Fahrenholtz, W. G.. (2023). Final‐stage densification kinetics of direct current–sintered ZrB2. in Journal of the American Ceramic Society
Wiley., 106(10), 5654-5661.
https://doi.org/10.1111/jace.19212
https://hdl.handle.net/21.15107/rcub_dais_15143

Stanfield AD, Smith SM, Filipović S, Obradović N, Buljak V, Hilmas GE, Fahrenholtz WG. Final‐stage densification kinetics of direct current–sintered ZrB2. in Journal of the American Ceramic Society. 2023;106(10):5654-5661.
doi:10.1111/jace.19212
https://hdl.handle.net/21.15107/rcub_dais_15143 .

Stanfield, Austin D., Smith, Steven M., Filipović, Suzana, Obradović, Nina, Buljak, Vladimir, Hilmas, Gregory E., Fahrenholtz, William G., "Final‐stage densification kinetics of direct current–sintered ZrB2" in Journal of the American Ceramic Society, 106, no. 10 (2023):5654-5661,
https://doi.org/10.1111/jace.19212 .,
https://hdl.handle.net/21.15107/rcub_dais_15143 .

TY  - JOUR
AU  - Stanfield, Austin D.
AU  - Smith, Steven M.
AU  - Filipović, Suzana
AU  - Obradović, Nina
AU  - Buljak, Vladimir
AU  - Hilmas, Gregory E.
AU  - Fahrenholtz, William G.
PY  - 2023
UR  - https://dais.sanu.ac.rs/123456789/15196
AB  - Final-stage sintering was analyzed for nominally phase pure zirconium diboride synthesized by borothermal reduction of high-purity ZrO2. Analysis was conducted on ZrB2 ceramics with relative densities greater than 90% using the Nabarro–Herring stress–directed vacancy diffusion model. Temperatures of 1900°C or above and an applied uniaxial pressure of 50 MPa were required to fully densify ZrB2 ceramics by direct current sintering. Ram travel data were collected and used to determine the relative density of the specimens during sintering. Specimens sintered between 1900 and 2100°C achieved relative densities greater than 97%, whereas specimens sintered below 1900°C failed to reach the final stage of sintering. The average grain size ranged from 1.0 to 14.7 μm. The activation energy was calculated from the slope of an Arrhenius plot that used the Kalish equation. The activation energy was 162 ± 34 kJ/mol, which is consistent with the activation energy for dislocation movement in ZrB2. The diffusion coefficients for dislocation motion that controls densification were 5.1 × 10−6 cm2/s at 1900°C and 5.1 × 10−5 cm2/s at 2100°C, as calculated from activation energy and average grain sizes. This study provides evidence that the dominant mechanism for final-stage sintering of ZrB2 ceramics is dislocation motion.
PB  - Wiley
T2  - Journal of the American Ceramic Society
T1  - Final‐stage densification kinetics of direct current–sintered ZrB2
SP  - 5654
EP  - 5661
VL  - 106
IS  - 10
DO  - 10.1111/jace.19212
UR  - https://hdl.handle.net/21.15107/rcub_dais_15196
ER  - 

@article{
author = "Stanfield, Austin D. and Smith, Steven M. and Filipović, Suzana and Obradović, Nina and Buljak, Vladimir and Hilmas, Gregory E. and Fahrenholtz, William G.",
year = "2023",
abstract = "Final-stage sintering was analyzed for nominally phase pure zirconium diboride synthesized by borothermal reduction of high-purity ZrO2. Analysis was conducted on ZrB2 ceramics with relative densities greater than 90% using the Nabarro–Herring stress–directed vacancy diffusion model. Temperatures of 1900°C or above and an applied uniaxial pressure of 50 MPa were required to fully densify ZrB2 ceramics by direct current sintering. Ram travel data were collected and used to determine the relative density of the specimens during sintering. Specimens sintered between 1900 and 2100°C achieved relative densities greater than 97%, whereas specimens sintered below 1900°C failed to reach the final stage of sintering. The average grain size ranged from 1.0 to 14.7 μm. The activation energy was calculated from the slope of an Arrhenius plot that used the Kalish equation. The activation energy was 162 ± 34 kJ/mol, which is consistent with the activation energy for dislocation movement in ZrB2. The diffusion coefficients for dislocation motion that controls densification were 5.1 × 10−6 cm2/s at 1900°C and 5.1 × 10−5 cm2/s at 2100°C, as calculated from activation energy and average grain sizes. This study provides evidence that the dominant mechanism for final-stage sintering of ZrB2 ceramics is dislocation motion.",
publisher = "Wiley",
journal = "Journal of the American Ceramic Society",
title = "Final‐stage densification kinetics of direct current–sintered ZrB2",
pages = "5654-5661",
volume = "106",
number = "10",
doi = "10.1111/jace.19212",
url = "https://hdl.handle.net/21.15107/rcub_dais_15196"
}

Stanfield, A. D., Smith, S. M., Filipović, S., Obradović, N., Buljak, V., Hilmas, G. E.,& Fahrenholtz, W. G.. (2023). Final‐stage densification kinetics of direct current–sintered ZrB2. in Journal of the American Ceramic Society
Wiley., 106(10), 5654-5661.
https://doi.org/10.1111/jace.19212
https://hdl.handle.net/21.15107/rcub_dais_15196

Stanfield AD, Smith SM, Filipović S, Obradović N, Buljak V, Hilmas GE, Fahrenholtz WG. Final‐stage densification kinetics of direct current–sintered ZrB2. in Journal of the American Ceramic Society. 2023;106(10):5654-5661.
doi:10.1111/jace.19212
https://hdl.handle.net/21.15107/rcub_dais_15196 .

Stanfield, Austin D., Smith, Steven M., Filipović, Suzana, Obradović, Nina, Buljak, Vladimir, Hilmas, Gregory E., Fahrenholtz, William G., "Final‐stage densification kinetics of direct current–sintered ZrB2" in Journal of the American Ceramic Society, 106, no. 10 (2023):5654-5661,
https://doi.org/10.1111/jace.19212 .,
https://hdl.handle.net/21.15107/rcub_dais_15196 .

TY  - JOUR
AU  - Obradović, Nina
AU  - Fahrenholtz, William G.
AU  - Filipović, Suzana
AU  - Corlett, Cole
AU  - Đorđević, Pavle
AU  - Rogan, Jelena
AU  - Vulić, Predrag J.
AU  - Buljak, Vladimir
AU  - Pavlović, Vladimir B.
PY  - 2019
UR  - https://dais.sanu.ac.rs/123456789/6949
AB  - Single phase MgAl2O4 was made from a one-to-one molar ratio of MgO and Al2O3 powders mixed using ball-milling. Mixtures of MgO and Al2O3 were subsequently treated in planetary ball mill for 30, 60, 90 and 120 minutes in air. The aim of this study was to examine phase composition, microstructure, and densification behavior of sintered specimens. After sintering in dilatometer at 1500 °C, the powder was converted to single phase MgAl2O4. The results show that mechanical activation improved the densification behavior of MgAl2O4 sintered specimens, and it reduced the onset temperature for sintering by approx. 100 oC. Based on dilatometer data, powders were subsequently densified at 1450 oC by hot pressing. Almost аll specimens exhibited full density, while sample activated for 30 minutes showed the fastest densification rate.
PB  - ETRAN
T2  - Science of Sintering
T1  - Characterization of MgAl2O4 sintered ceramics
SP  - 363
EP  - 376
VL  - 51
IS  - 4
DO  - 10.2298/SOS1904363O
UR  - https://hdl.handle.net/21.15107/rcub_dais_6949
ER  - 

@article{
author = "Obradović, Nina and Fahrenholtz, William G. and Filipović, Suzana and Corlett, Cole and Đorđević, Pavle and Rogan, Jelena and Vulić, Predrag J. and Buljak, Vladimir and Pavlović, Vladimir B.",
year = "2019",
abstract = "Single phase MgAl2O4 was made from a one-to-one molar ratio of MgO and Al2O3 powders mixed using ball-milling. Mixtures of MgO and Al2O3 were subsequently treated in planetary ball mill for 30, 60, 90 and 120 minutes in air. The aim of this study was to examine phase composition, microstructure, and densification behavior of sintered specimens. After sintering in dilatometer at 1500 °C, the powder was converted to single phase MgAl2O4. The results show that mechanical activation improved the densification behavior of MgAl2O4 sintered specimens, and it reduced the onset temperature for sintering by approx. 100 oC. Based on dilatometer data, powders were subsequently densified at 1450 oC by hot pressing. Almost аll specimens exhibited full density, while sample activated for 30 minutes showed the fastest densification rate.",
publisher = "ETRAN",
journal = "Science of Sintering",
title = "Characterization of MgAl2O4 sintered ceramics",
pages = "363-376",
volume = "51",
number = "4",
doi = "10.2298/SOS1904363O",
url = "https://hdl.handle.net/21.15107/rcub_dais_6949"
}

Obradović, N., Fahrenholtz, W. G., Filipović, S., Corlett, C., Đorđević, P., Rogan, J., Vulić, P. J., Buljak, V.,& Pavlović, V. B.. (2019). Characterization of MgAl2O4 sintered ceramics. in Science of Sintering
ETRAN., 51(4), 363-376.
https://doi.org/10.2298/SOS1904363O
https://hdl.handle.net/21.15107/rcub_dais_6949

Obradović N, Fahrenholtz WG, Filipović S, Corlett C, Đorđević P, Rogan J, Vulić PJ, Buljak V, Pavlović VB. Characterization of MgAl2O4 sintered ceramics. in Science of Sintering. 2019;51(4):363-376.
doi:10.2298/SOS1904363O
https://hdl.handle.net/21.15107/rcub_dais_6949 .

Obradović, Nina, Fahrenholtz, William G., Filipović, Suzana, Corlett, Cole, Đorđević, Pavle, Rogan, Jelena, Vulić, Predrag J., Buljak, Vladimir, Pavlović, Vladimir B., "Characterization of MgAl2O4 sintered ceramics" in Science of Sintering, 51, no. 4 (2019):363-376,
https://doi.org/10.2298/SOS1904363O .,
https://hdl.handle.net/21.15107/rcub_dais_6949 .