Influences of ZrSiO4 doping on microstructure and mechanical properties of Y2SiO5–ZrSiO4 ceramics

Abstract A series of (1-x)Y2SiO5-xZrSiO4 (x = 0, 10, 20, 30, 40, mol. %) ceramics were successfully fabricated at 1500 °C. The influences of ZrSiO4 doping concentration on microstructure, mechanical properties, and sintering behavior of Y2SiO5–ZrSiO4 ceramics were investigated. The results showed that Y2SiO5–ZrSiO4 ceramics were composed of Y2SiO5, Y2Si2O7, and c-ZrO2 three phases. Both the fracture toughness and elastic modulus of Y2SiO5–ZrSiO4 ceramics first increased, and then decreased with the ZrSiO4 doping concentration increasing. In particular, the fracture toughness of 0.7Y2SiO5-0.3ZrSiO4 ceramic was the largest among those Y2SiO5–ZrSiO4 ceramics investigated, which was nearly twice as high as that of pure Y2SiO5. The phase composition and microstructure of 0.7Y2SiO5-0.3ZrSiO4 ceramic remained practically unchanged and the fracture toughness was about 3.04 MPa m1/2 after sintering at 1400 °C for 100 h, indicating that 0.7Y2SiO5-0.3ZrSiO4 ceramic possessed good sintering resistance at 1400 °C.