We analysed with different methods the densification of UO2 nanopowders in SPS under constant heating rate (CHR) and isothermal sintering conditions. The apparent activation energy of densification in SPS (75 kJ/mol with CHR method) is significantly smaller than in conventional sintering. It is shown that this is likely not an effect of the applied current. We also observed a threshold stress at 64 MPa for the transition from pressure-insensitive sintering (stress exponent n approximate to 0) to pressure-assisted sintering, suggesting that the contribution of the capillary stresses in such nanopowders is comparable with the typical stress applied in SPS.

Spark plasma sintering of UO2 nanopowders: Pressure, heating rate and current effects / Margueret, A.; Balice, L.; Popa, K.; Holzhäuser, M.; De Bona, E.; Bonani, W.; Bulgheroni, A.; Audubert, F.; Cologna, M.. - In: JOURNAL OF THE EUROPEAN CERAMIC SOCIETY. - ISSN 0955-2219. - 42:13(2022), pp. 6056-6066. [10.1016/j.jeurceramsoc.2022.05.070]

Spark plasma sintering of UO2 nanopowders: Pressure, heating rate and current effects

De Bona E.;Bonani W.;Cologna M.
2022-01-01

Abstract

We analysed with different methods the densification of UO2 nanopowders in SPS under constant heating rate (CHR) and isothermal sintering conditions. The apparent activation energy of densification in SPS (75 kJ/mol with CHR method) is significantly smaller than in conventional sintering. It is shown that this is likely not an effect of the applied current. We also observed a threshold stress at 64 MPa for the transition from pressure-insensitive sintering (stress exponent n approximate to 0) to pressure-assisted sintering, suggesting that the contribution of the capillary stresses in such nanopowders is comparable with the typical stress applied in SPS.
2022
13
Margueret, A.; Balice, L.; Popa, K.; Holzhäuser, M.; De Bona, E.; Bonani, W.; Bulgheroni, A.; Audubert, F.; Cologna, M.
Spark plasma sintering of UO2 nanopowders: Pressure, heating rate and current effects / Margueret, A.; Balice, L.; Popa, K.; Holzhäuser, M.; De Bona, E.; Bonani, W.; Bulgheroni, A.; Audubert, F.; Cologna, M.. - In: JOURNAL OF THE EUROPEAN CERAMIC SOCIETY. - ISSN 0955-2219. - 42:13(2022), pp. 6056-6066. [10.1016/j.jeurceramsoc.2022.05.070]
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11572/445430
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 7
  • ???jsp.display-item.citation.isi??? 4
  • OpenAlex ND
social impact