In order to improve the mechanical properties of 8YSZ ceramic, the 8YSZ bimodal particle sizes powders were dry pressed and pressureless sintered. The molding process parameters including the molding pressure, pressure holding time and dosage of binder were optimized. The sintering scheme based on orthogonal test was designed. The influence of the sintering process parameters including sintering temperature, heating rate, holding time, sintering method on the sintering properties and mechanical properties of 8YSZ was discussed and their optimization value were obtained. The results show that the green ceramic with the relative density of 54.9% can be obtained by adopting the optimized molding process parameters with the dosage of PVA of 10%(mass fraction), the forming pressure of 10MPa, the pressure holding time of 30s. The 8YSZ ceramic with the relative density of 98.3% and the bending strength of 100.3MPa can be prepared by adopting the optimized sintering process parameters with the sintering temperature of 1500℃, holding time of 4h, heating rate of 5℃/min, sintering methods of naked burning.
The effect order on experimentspecifications and the optimal level
Experiment specification
Relative density
Bending strength
Sintering temperature
1500℃(A3)
1500℃(A3)
Holding time
4h(C3)
4h(C3)
Heating rate
5℃/min(B2)
5℃/min(B2)
Sintering methods
Uncovered sintering(D3)
Covered sintering(D1)
Table 5 正交实验各影响因素优化结果
Fig.10 优化工艺参数下制备出的试样表面微观形貌图
1
韩敏芳, 彭苏萍. 固体氧化物燃料电池材料及准备[M]. 北京: 科学出版社, 2004.
1
HAN Min-fang, PENG Su-ping. The Solid Oxide Fuel Cell Material and Preparation[M]. Beijing: Science Press, 2004.
2
TEKELI S, ERDOGAN M, AKTAS B Influence of a-Al2O3 addition on sintering and grain grow behaviour of 8 mol% Y2O3-stabilised cubic zirconia(c-ZrO2)[J]. Ceramics International, 2004, 30 (8): 2203- 2209.
ZHOU Hong-ming, LI Miao-lei, GUO Yan-jun, et al Effect of MnO2 activated sintering and properties of 8YSZ at low temperature[J]. Journal of Central South University, 2012, 43 (4): 1254- 1260.
JIANG Hong, GUO Rui-song, REN Jian-xun Effect of ZnO on 8YSZ electrolyte materials sintered property and electrochemical properties[J]. Journal of the Chinese Ceramic Society, 2010, 38 (8): 1434- 1439.
6
CHRISTEL L R, FLORENCE A, DELOGET C, et al Dense yttria stabilized zirconia: sintering and microstructure[J]. Ceramics International, 2003, 29, 151- 158.
7
LEE Shinn-Yih Sintering behavior and mechanical properties of injection-molded zirconia powder[J]. Ceramics International, 2004, 30, 579- 584.
FAN Ji-jun, FAN Yu-tao, CHEN Rong-min, et al Influence of different forming methods on the sintering properties of nano Y-TZP ceramics[J]. Nano Machining Technology, 2006, 3 (1): 32- 35.
HU Yu-yan, HUANG Xiao-wei Study on the properties of the liquid phase sintering of 8YSZ ceramics[J]. Bulletin of the Chinese Ceramic Society, 2007, 26 (6): 1178- 1183.
LI Hong-feng, YU Ze-min, JIN Li-guo, et al The effect of molding pressure on the mechanical properties of ZrO2 ceramics[J]. Journal of Harbin University of Science and Technology, 2004, 9 (6): 44- 46.
LIU Xiao-guang, CHEN Da-ming, TONG Jian-feng, et al Effects of sintering temperature on microstructure and properties of 8%Y2O3-ZrO2 ceramic[J]. Journal of Materials Engineering, 2008, (4): 44- 50.
REN Ji-wen, PENG Pei, ZHANG Hong-hai Study on sintering process of yttrium stabilized zirconia nano powder[J]. Journal of Materials Engineering, 2009, (2): 38- 42.