Microstructural and optical properties of MgAl2O4 Spinel: Effect of Mechanical Activation, Yttrium and Graphene addition
Authors
Obradović, Nina
Fahrenholtz, William G.

Corlett, Cole
Filipović, Suzana

Nikolić, Marko G.

Marinković, Bojan A.

Failla, Simone
Sciti, Diletta
Sani, Elisa
Conference object (Published version)
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Magnesium aluminate and other alumina-based spinels attract attention due to their high hardness, high mechanical strength, and low dielectric constant. MgAl2O4 was produced by solid-state reaction between MgO and α-Al2O3 powders. Mechanical activation of 30 minutes in a planetary ball mill was used to increase the reactivity of powders. Yttrium oxide and graphene were added to prevent abnormal grain growth during sintering. Samples were sintered by hot-pressing under vacuum at 1450 °C. Phase composition and microstructure of sintered specimens were characterized by X-ray diffraction analysis and scanning electron microscopy. Rietveld analysis revealed 100 % pure spinel phase in all sintered specimens, and decrease in crystallite size with the addition of yttria or graphene. Density measurements indicated that the mechanically activated specimen reached 99.6 % relative density, while other specimens were above 96.5 % relative density. Furthermore, the highest solar absorbance and highe...st spectral selectivity as a function of temperature were detected for the mechanically activated specimen with graphene addition. Mechanical activation is an efficient method to improve the densification behaviour of MgAl2O4 produced from mixed oxide powders, while additives improve microstructure and optical properties.
Keywords:
MgAl2O4 / solid-state reaction / magnesium aluminate / mechanical activation / yttrium oxide / ball milling / oxide powdersSource:
Program and the Book of abstracts / Serbian Ceramic Society Conference Advanced Ceramics and Application IX : New Frontiers in Multifunctional Material Science and Processing, Serbia, Belgrade, 20-21. September 2021, 2021, 92-92Publisher:
- Belgrade : Serbian Ceramic Society
Funding / projects:
Institution/Community
Институт техничких наука САНУ / Institute of Technical Sciences of SASATY - CONF AU - Obradović, Nina AU - Fahrenholtz, William G. AU - Corlett, Cole AU - Filipović, Suzana AU - Nikolić, Marko G. AU - Marinković, Bojan A. AU - Failla, Simone AU - Sciti, Diletta AU - Sani, Elisa PY - 2021 UR - https://dais.sanu.ac.rs/123456789/11895 AB - Magnesium aluminate and other alumina-based spinels attract attention due to their high hardness, high mechanical strength, and low dielectric constant. MgAl2O4 was produced by solid-state reaction between MgO and α-Al2O3 powders. Mechanical activation of 30 minutes in a planetary ball mill was used to increase the reactivity of powders. Yttrium oxide and graphene were added to prevent abnormal grain growth during sintering. Samples were sintered by hot-pressing under vacuum at 1450 °C. Phase composition and microstructure of sintered specimens were characterized by X-ray diffraction analysis and scanning electron microscopy. Rietveld analysis revealed 100 % pure spinel phase in all sintered specimens, and decrease in crystallite size with the addition of yttria or graphene. Density measurements indicated that the mechanically activated specimen reached 99.6 % relative density, while other specimens were above 96.5 % relative density. Furthermore, the highest solar absorbance and highest spectral selectivity as a function of temperature were detected for the mechanically activated specimen with graphene addition. Mechanical activation is an efficient method to improve the densification behaviour of MgAl2O4 produced from mixed oxide powders, while additives improve microstructure and optical properties. PB - Belgrade : Serbian Ceramic Society C3 - Program and the Book of abstracts / Serbian Ceramic Society Conference Advanced Ceramics and Application IX : New Frontiers in Multifunctional Material Science and Processing, Serbia, Belgrade, 20-21. September 2021 T1 - Microstructural and optical properties of MgAl2O4 Spinel: Effect of Mechanical Activation, Yttrium and Graphene addition SP - 92 EP - 92 UR - https://hdl.handle.net/21.15107/rcub_dais_11895 ER -
@conference{ author = "Obradović, Nina and Fahrenholtz, William G. and Corlett, Cole and Filipović, Suzana and Nikolić, Marko G. and Marinković, Bojan A. and Failla, Simone and Sciti, Diletta and Sani, Elisa", year = "2021", abstract = "Magnesium aluminate and other alumina-based spinels attract attention due to their high hardness, high mechanical strength, and low dielectric constant. MgAl2O4 was produced by solid-state reaction between MgO and α-Al2O3 powders. Mechanical activation of 30 minutes in a planetary ball mill was used to increase the reactivity of powders. Yttrium oxide and graphene were added to prevent abnormal grain growth during sintering. Samples were sintered by hot-pressing under vacuum at 1450 °C. Phase composition and microstructure of sintered specimens were characterized by X-ray diffraction analysis and scanning electron microscopy. Rietveld analysis revealed 100 % pure spinel phase in all sintered specimens, and decrease in crystallite size with the addition of yttria or graphene. Density measurements indicated that the mechanically activated specimen reached 99.6 % relative density, while other specimens were above 96.5 % relative density. Furthermore, the highest solar absorbance and highest spectral selectivity as a function of temperature were detected for the mechanically activated specimen with graphene addition. Mechanical activation is an efficient method to improve the densification behaviour of MgAl2O4 produced from mixed oxide powders, while additives improve microstructure and optical properties.", publisher = "Belgrade : Serbian Ceramic Society", journal = "Program and the Book of abstracts / Serbian Ceramic Society Conference Advanced Ceramics and Application IX : New Frontiers in Multifunctional Material Science and Processing, Serbia, Belgrade, 20-21. September 2021", title = "Microstructural and optical properties of MgAl2O4 Spinel: Effect of Mechanical Activation, Yttrium and Graphene addition", pages = "92-92", url = "https://hdl.handle.net/21.15107/rcub_dais_11895" }
Obradović, N., Fahrenholtz, W. G., Corlett, C., Filipović, S., Nikolić, M. G., Marinković, B. A., Failla, S., Sciti, D.,& Sani, E.. (2021). Microstructural and optical properties of MgAl2O4 Spinel: Effect of Mechanical Activation, Yttrium and Graphene addition. in Program and the Book of abstracts / Serbian Ceramic Society Conference Advanced Ceramics and Application IX : New Frontiers in Multifunctional Material Science and Processing, Serbia, Belgrade, 20-21. September 2021 Belgrade : Serbian Ceramic Society., 92-92. https://hdl.handle.net/21.15107/rcub_dais_11895
Obradović N, Fahrenholtz WG, Corlett C, Filipović S, Nikolić MG, Marinković BA, Failla S, Sciti D, Sani E. Microstructural and optical properties of MgAl2O4 Spinel: Effect of Mechanical Activation, Yttrium and Graphene addition. in Program and the Book of abstracts / Serbian Ceramic Society Conference Advanced Ceramics and Application IX : New Frontiers in Multifunctional Material Science and Processing, Serbia, Belgrade, 20-21. September 2021. 2021;:92-92. https://hdl.handle.net/21.15107/rcub_dais_11895 .
Obradović, Nina, Fahrenholtz, William G., Corlett, Cole, Filipović, Suzana, Nikolić, Marko G., Marinković, Bojan A., Failla, Simone, Sciti, Diletta, Sani, Elisa, "Microstructural and optical properties of MgAl2O4 Spinel: Effect of Mechanical Activation, Yttrium and Graphene addition" in Program and the Book of abstracts / Serbian Ceramic Society Conference Advanced Ceramics and Application IX : New Frontiers in Multifunctional Material Science and Processing, Serbia, Belgrade, 20-21. September 2021 (2021):92-92, https://hdl.handle.net/21.15107/rcub_dais_11895 .