Artigo de peri??dico
Liquid-phase flash sintering 8YSZ with alkali halide sintering aids
Registro en:
0955-2219
12
40
10.1016/j.jeurceramsoc.2020.03.022
0000-0002-8598-279X
94.83
88.50
Autor
DIAZ, J.C.C.A.
MUCCILLO, R.
Resumen
The properties of ZrO2: 8 mol% Y2O3 (8YSZ) ceramics with LiF and KCl sintering aids for liquid phase formation
during electric field-assisted sintering were studied. Sintering experiments were carried out at 650 ??C under
200 V cm???1 AC electric field by varying current density, current application time, as well as LiF and KCl contents.
Pellets sintered with KCl addition had cavities, cracks and fractures. Pellets sintered with 15 wt.% LiF, on
the other hand, were homogeneous after thermal removal of LiF upon Joule heating. Low electric current
densities coupled with longer application times produced homogeneous specimens. Three different stages were
identified during sintering experiments: (i) LiF melting with the electric field applied at furnace temperatures
lower than its melting point, (ii) shrinkage due to liquid phase formation and LiF removal, (iii) final densification
due to grain growth and pore elimination. The electrical behavior and an estimate of the porosity were carried
out by electrochemical impedance spectroscopy measurements. Conselho Nacional de Desenvolvimento Cient??fico e Tecnol??gico (CNPq) Funda????o de Amparo ?? Pesquisa do Estado de S??o Paulo (FAPESP) CNPq: 302357/2018-1; 305889/2018-4 FAPESP: 13/07296-2; 18/13620-0