Effect of Sintering Temperature on Biaxial Flexural Strength of Y-TZP

Objective: , this study aimed to compare the effect of sintering temperature on biaxial flexural strength of Y-TZP.

Methods: , Y-TZP powders with different particle sizes were sintered using various heating schedules to determine the effect on strength. Tosoh TZ-3YSB-E (about 0.2 microns particle size) and TZ-3YB-E (about 0.1 microns particle size) were pressed uniaxially in a 19 mm diameter steel mold @ 78 MPa (11 ksi) and then isostatically pressed at 138 MPa (20 ksi). The blocks were then sintered to approximately 50% theoretical density and sliced to produce discs. Discs were sintered at 1350 ^oC and 1500 ^oC to full density using a Vita ZYrcomatT furnace (Vita Zahnfabrik). Final dimensions of each disc were 14.8 mm diameter and 1.2 mm thick. Specimens were divided into 4 groups; TZ-3YSB-E@1350^oC, TZ-3YSB-E@1500^oC, TZ-3YB-E@1350^oC and TZ-3YB-E@1500^oC.  Based on Tosoh recommendations, 3YSB@1350C discs are “underfired”, and 3YB@1500C discs are “overfired”. Biaxial flexural strength was determined using a ball on three ball apparatus at a cross head speed of 1 mm/min. N = 25/group.

Results: , biaxial Flexural Strength

 

Group	Strength (MPa)	Significant Difference	Weibull Analysis
			Modulus	Characteristic Strength
TZ-3YSB-E 1350 oC	1074.1 ± 85.2	A	15.65	1111.65
TZ-3YSB-E 1500 oC	1149.8 ± 80.8	B	16.06	1186.47
TZ-3YB-E 1350 oC	1151.2 ± 113.5	B	13.29	1198.14
TZ-3YB-E 1500 oC	1111.2 ± 86.7	AB	14.28	1151.13

Data were analyzed with Weibull and ANOVA/Tukey tests (p=0.05). Group with the same letter are Not significantly different.

Conclusion: , sintering temperature may have a significant effect on biaxial flexural strength of TZ-3YSB-E.