Mechanism of Sintering YAG/ZrB₂ Multiphase Ceramics with Spark Plasma Sintering

Abstract

Although ZrB₂ has some excellent performances, it is difficult to prepare the high relative-density ZrB₂ ceramics, which limits the application of ZrB₂ materials. To obtain higher relative-density ZrB₂ ceramics for increasing the good oxidation resistance, YAG/ZrB₂ multiphase ceramics is prepared with the spark plasma sintering, the sintering mechanism of preparing YAG/ZrB₂ multiphase ceramic materials is investigated. Al₂O₃ reacts with Y₂O₃ to form YAG above 700°C during the sintering process. YAG is filled and melted the space of ZrB₂ particles to bind the ZrB₂ particles during reaction and sintering process, which increases the density of YAG/ZrB₂ multiphase ceramic materials. The YAG/ZrB₂ multiphase ceramic materials was successfully prepared under sintering temperature of 1700°C, holding temperature time for 4 min, and sintering pressure of 20 MPa; the density is 5.63 g/cm³, the relative density is 99.78%.

Keywords:

• High-temperature materials
• Multiphase ceramics
• Relative density
• Sintering
• YAG
• ZrB₂

ACKNOWLEDGMENTS

The authors are thankful for the financial support provided by the National Science Foundation of China, and for the apparatus provided by The Center for Materials Test of Wuhan University of Technology, China.