Y-TZP-AlO复相陶瓷的力学性能研究.doc

3Y-TZP-Al2O3复相陶瓷的力学性能研究 3Y-TZP/Al2O3复相陶瓷的力学性能研究 摘 要 ZTA复相陶瓷具有良好的性能，在许多领域都得到广泛的应用。本实验以纳米3Y-TZP和微米Al2O3为主要原料，采用常压烧结法制备致密的纳米ZTA复相陶瓷材料。分别探讨不同氧化锆含量对材料致密化、相组成、显微结构以及力学性能的影响。 实验结果表明，ZTA复相陶瓷的相对密度会随着3Y-TZP含量的升高而先上升后降低。纳米3Y-TZP颗粒能够分布在基体颗粒的晶界，从而使试样的相对密度升高。当3Y-TZP含量为30wt%时，其相对密度达到最高，如烧结温度为1400℃，试样的相对密度高达96.35%。若继续提高3Y-TZP含量，其相对密度因过多的纳米颗粒团聚而下降。并且在一定的烧结温度范围内，ZTA复合陶瓷的相对密度会随着烧结温度的升高而增大。经机械混合后的粉料的晶相组成主要为α-Al2O3和t-ZrO2。而经过高温烧结后，试样中的晶相组成为α-Al2O3、t-ZrO2和一定量的m-ZrO2。在烧结温度范围内，试样中的颗粒会随着烧结温度的升高而增大，Al2O3颗粒随着3Y-TZP含量的增加而变小。纳米级的3Y-TZP颗粒会形成“內晶型”结构。在烧结温度为1450℃时，含30wt%3Y-TZP的试样抗弯强度高达441.22MPa。纳米颗粒抑制颗粒的长大，细晶能够阻碍裂纹的扩展，而提高试样的力学性能。 关键词：3Y-TZP，复相陶瓷，力学性能 I Reseach of Mechanical Properties for the 3Y-TZP/Al2O3 Composite Ceramics Abstract ZTA composite ceramics have been widely used in many areas with the good performance. In the experiment, 3Y-TZP and Al2O3 as raw materials, the dense nano ZTA composite ceramics were prepared by pressureless sintering. Effects of different zirconia content on the densification, microstructure, phase composition and mechanical properties of 3Y-TZP/Al2O3 composite ceramics were investigated. The results show that density of ZTA composite ceramics will first increase and then decrease when the 3Y-TZP content increase. 3Y-TZP nano-particles can be distributed over particles in the matrix grain boundaries, so that the sample density increased. When the 3Y-TZP content was 30wt%, its highest density, such as sintering temperature is 1400℃, the density as high as 96.35%. If you continue to improve the content of 3Y-TZP, the density will decline due to the excessive nano-particle agglomeration. And in a range of Sintering temperature, ceramic density will increase with the increase of sintering temperature. The phase of powder with mechanical mixture mainly composed of α-Al2O3 and t-ZrO2. With high temperature sintering, the phase in specimen is α-Al2O3, t-ZrO2 and m-ZrO2. In the sintering temperature range, particles will become lage