Modification Effect of Nanometre Zirconia on Ca-PSZ Ceramics

Abstract

The modified calcium oxide partially stabilized zirconia ceramics were fabricated using ZrO2 powder as raw materials, CaO as stabilizer, and nanometre zirconia as modification agent. The relationship between additive amount of nanometre zirconia and the performance of Ca-PSZ ceramics were researched via testing the physical properties, analyzing mineral phase composition, and observing microstructure of the samples. The results show that the introduction of nanometre zirconia powder has a significant effect on the physical properties of Ca-PSZ, with an addition of 8wt%, bulk density was up to 5.08 g/cm3, and the compressive strength reached 381 MPa. Compared with the unmodified Ca-PSZ sample, the porosity of the modified Ca-PSZ samples decreased by 40%, and the compressive strength increased by 70%. The introduction of nanometre zirconia has an inhibitory effect on the abnormal growth of zirconia grains and improves the densification of the Ca-PSZ ceramics. Through the formation of intragranular structure, nanometre zirconia can induce transgranular fracture and weaken crystalline fracture, thereby increasing the strength of the Ca-PSZ ceramics.