浆料的固相含量对注凝成型氧化锆增韧氧化铝陶瓷的影响

EFFECT OF SOLID VOLUME FRACTION OF SLURRIES ON PROPERTIES OF ZIRCONIA- TOUGHENED ALUMINA COMPOSITE CERAMICS BY GELCASTING

研究了浆料的固相体积分数对注凝成型氧化锆增韧氧化铝(zirconia toughenedalumina,ZTA)生坯和烧结样品物理力学性能的影响。实验所用Al2O3和ZrO2的质量比为80∶20。用压汞法分析了生坯的孔结构,结果表明:高固相体积分数浆料制备的生坯孔结构呈双峰分布。SEM和XRD研究显示了高固相体积分数浆料制备的烧结体具有结构致密、ZrO2分布均匀和tZrO2含量高等特点。采用55%固相体积分数的桨料制备的坯体,经1600℃烧结2h后,ZTA样品的抗弯强度和断裂韧性分别达631.5MPa和7.64MPa·m1/2。

The effect of solid volume fraction in slurries on physico-mechanical properties was investigated for zirconia-toughened alumina (ZTA) green and sintering bodies prepared by gelcasting process. The mass ratio of Al2O3 and ZrO2 was 80:20 in experiment. The pore structures of green bodies were analyzed with the mercury intrusion method. The results indicate that pore distribution of green bodies prepared by slurries with high solid volume fraction appears double peaks. SEM photographs and XRD patterns show that sintered samples made by slurries with high solid volume fraction have a higher densification structure, homogeneous distribution of ZrO2 particle and higher content of t-ZrO2, phase. The bending strength and fracture toughness of the ZTA ceramics prepared by the slurry with 55% solid volume fraction and sintered at 1600°C for 2 h can be reached to 631.5 MPa and 7.64 MPa &middot m1/2, respectively.