Yttria-stabilized tetragonal zirconia prepared using gel casting and two-stage sintering

Figures & data

Figure 1. Rheological behaviors of the YTZP slurries added with different amounts of dispersants (a) D-821A; (b) CE64.

Table 1. Comparison of the slurry viscosity of the result with those reported in the literature.

particle size	dispersant	solid content (vol%)	pH	Viscosity (Pa s)	reference
94 nm	CE64 0.2 wt%	45	10	0.24 @0.1 s^−1	this study
60 nm	CE64 0.5 wt%	20	8	7.5 @0.1 s^−1	[21]
95 nm	NH4PAA	45	7.1	7.5 @5 s^−1	[24]
100 nm	NH4PAA 1 wt%	14.2	8	4.5 @0.1 s^−1	[25]

Figure 2. Cumulative particle size distribution of the YTZP slurry added with 0.2 wt% CE64.

Figure 3. (a) Effect of the solid content on the rheological behaviors of YTZP slurries with 0.2 wt% CE64; (b) Effect of adding different organic components on the viscosity of the YTZP slurry.

Figure 4. (a) FTIR spectroscopies of the products obtained by mixing EGDGE and DPTA for various reaction time (0 min to 30 min); (b) Effect of CE64 addition on the polymerization rate measured by FTIR spectroscopy; (c) Effect of HQ addition on the polymerization rate measured by FTIR spectroscopy.

Figure 5. Effects of different curing temperatures and gelation times on the viscosity (at the shear rate of 10s⁻¹) of the slurry with 45 vol% solid content (the mixture of EGDGE, DPTA, HQ, and 0.2 wt% CE64).

Figure 6. SEM microstructure of the green body prepared by gel casting and CIP process.

Figure 7. Variation of the shrinkage and instantaneous relative density with the temperature for the YTZP green body.

Figure 8. SEM microstructure of the polished surface following thermal etching (1200°C for 30 min) of a two-stage sintered (first stage sintering temperature: 1300°C, second stage sintering temperature: 1240°C for 24 hours) YTZP ceramic.

Figure 9. Cumulative grain size distribution of YTZP ceramics after two-stage sintering (first stage sintering temperature:1300°C, the second stage sintering: 1240°C for 24 h).

Figure 10. XRD pattern of the YTZP ceramic after two-stage sintering.

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