Abstract
Alumina (Al 2O 3) and alumina–yttria stabilized zirconia (YSZ) composites containing 3 and 5 mass% ceria (CeO 2) were prepared by spark plasma sintering (SPS) at temperatures of 1350–1400 °C for 300 s under a pressure of 40 MPa. Densification, microstructure and mechanical properties of the Al 2O 3 based composites were investigated. Fully dense composites with a relative density of approximately 99% were obtained. The grain growth of alumina was inhibited significantly by the addition of 10 vol% zirconia, and formation of elongated CeAl 11O 18 grains was observed in the ceria containing composites sintered at 1400 °C. Al 2O 3–YSZ composites without CeO 2 had higher hardness than monolithic Al 2O 3 sintered body and the hardness of Al 2O 3–YSZ composites decreased from 20.3 GPa to 18.5 GPa when the content of ZrO 2 increased from 10 to 30 vol%. The fracture toughness of Al 2O 3 increased from 2.8 MPa m 1/2 to 5.6 MPa m 1/2 with the addition of 10 vol% YSZ, and further addition resulted in higher fracture toughness values. The highest value of fracture toughness, 6.2 MPa m 1/2, was achieved with the addition of 30 vol% YSZ.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
