以ZrSiO4-Al2O3高岭土为主要原料,长石等作为烧结助剂,在1220~1340℃之间制备出了致密的ZrSi04-A120。(5~43wt%Al2O3)复相陶瓷。研究了Al2O3含量、烧结温度对复相陶瓷显微结构及力学性能的影响。结果表明,复相陶瓷的物相包括ZrSiO4-Al2O3适当提高烧结温度有助于试样的致密化;引入的Al2O3通过颗粒增强、裂纹偏转、细晶强化等机制对ZrSiO4陶瓷起到了一定的增强增韧作用。1500℃烧结制得的添加25wt%Al2O3的复相陶瓷具有最佳的力学性能,其抗弯强度达到181MPa,断裂韧性为5.00MPa·m1/2,维氏硬度为7.0GPa。
ZrSiO4-Al2O3 (5- 43 wt%A1203) composite ceramics were prepared by direct sintering zircon, alumina and kaolin during 1220- 1340 ℃ . Feldspar was added as sintering aids. The effects of Al2O3 content, sintering temperature on microstructure and mechanical properties of ZrSiQ-Al2O3 composite ceramics were studied. The result showed that the phase in the samples includes ZrSiQ and Al2O3 An appropriate increase in the sintering temperature was benefit to the densification of the samples Al2O3 can improve the mechanical properties of the compositeceramics by the mechanism of particle reinforcement, crack deflection and refined crystalline strengthening. The ZrSiO4-Al2O3 (25 wt% Al2O3 composite ceramics sintered at 1300℃ have the best mechanical properties, the bending strength, fracturetoughness, vickers hardness of the composite ceramics can reach 181 MPa, 3.00 MPa'm1/2 and 7.0 GPa.