abstract
This study investigated the combination of Direct Ink Writing (DIW) and Flash Sintering of zirconia stabilized with 3 mol. % Y2O3 (3Y-TZP). The samples were printed in two stacking configurations, and flash sintering was performed without current ramp control (FS) and using current ramp (CRFS) for comparison purposes. In both conditions, an electric field of 80 V cm-1 and a current density of 150 mA mm-2 were applied. The physical, microstructural, and mechanical properties of the printed samples were evaluated. The stacking configuration influenced both the grain size gradients and mechanical properties. Furthermore, controlling the current density ramp resulted in a slight homogenization of the grains' size across different regions of the sample (core, edge, and flat surfaces). The presence of zirconia polymorphs, such as ZrO2-t and ZrO2-c, as well as a distorted form of the tetragonal phase (ZrO2-t'), was observed in the samples. These phases were affected by both the printing strategy and the current ramp control during the flash sintering step. In addition, the samples demonstrated typical values of Vickers hardness for 3Y-TZP (ranging from 10.5 to 11.8 GPa) and fracture toughness (ranging from 3.6 to 4.7 MPa m1/2), with a minor current density ramp control influence. Therefore, both FS and CRFS techniques represent viable pathways for producing dense 3D printed ceramic materials.
keywords
ZIRCONIA CERAMICS; ZNO; MICROSTRUCTURE; PHOTOEMISSION; PHASE; FIELD; YSZ
subject category
Materials Science
authors
Nunes, FC; Alves, MFRP; Olhero, SM; Lévaro, NRM; Pallone, EMJA; Santos, C
our authors
Manuel Fellipe Rodrigues Pais Alves
PhD Student
Susana Maria Henriques Olhero
Assistant ProfessorProjects
CICECO - Aveiro Institute of Materials (UIDB/50011/2020)
CICECO - Aveiro Institute of Materials (UIDP/50011/2020)
Associated Laboratory CICECO-Aveiro Institute of Materials (LA/P/0006/2020)
acknowledgements
This study was financed by the grant 22/05031-0 and 22/10604-0, Sao Paulo Research Foundation (FAPESP) , Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior-Brazil (CAPES) -Finance Code 001, and National Council for Scientific and Technological Development (CNPq) , grant 305532-2021-9. The project CICECO-Aveiro Institute of Materials, UIDB/50011/2020, UIDP/50011/2020 & LA/P/0006/2020, financed by national funds through the FCT/MEC (PIDDAC) is also acknowledged. M.F.R.P. acknowledges the FCT for the PhD grant (2021.06615.BD) .r acknowledged. M.F.R.P. acknowledges the FCT for the PhD grant (2021.06615.BD) .