烧结温度对振荡压力烧结工艺制备高性能氧化锆陶瓷的影响

Effect of Sintering Temperature on the Structures and Properties of High Quality Zirconia Ceramics under Oscillatory Pressure

摘要:

本文采用新型振荡压力烧结技术制备了高性能氧化锆陶瓷,并系统研究了该工艺中烧结温度对于氧化锆陶瓷中致密度、晶粒尺寸、微观结构以及力学性能的影响关系。结果表明：振荡压力烧结工艺中,随着烧结温度的提高,氧化锆试样致密度变化不明显,但晶粒尺寸在不断增加,试样表面均几乎无气孔,当目标温度达到1300℃时,氧化锆陶瓷的硬度和抗弯强度均最大,分别为16.6GPa和1455MPa。相比常压和热压烧结工艺,振荡压力的引入明显降低了氧化锆陶瓷的致密化温度,且获得了更高的力学强度和断裂可靠性。

Abstract:

In this paper, oscillatory pressure sintering technique (OPS) was used to prepare high quality zirconia ceramics. The effects of sintering temperature on the density, grain size, microstructure and mechanical properties of zirconia ceramics were firstly investigated. The results show that under the application of oscillatory pressure, the variation of relative densities is not obvious while the grain sizes significantly increase during the increased sintering temperature. All specimens reached a nearly full density as there was scarcely any pores on the polished surface. The highest hardness and bending strength of 16.6 GPa and 1455 MPa, respectively, are reached when the target temperature reaches 1300°C. Compared with conventional pressureless and hot pressure sintering process, the introduction of oscillatory pressure significantly reduces the densification temperature of zirconia ceramics, and evidently enhances mechanical strength and fracture reliability.