Study on Fracture Behavior of Alumina Ceramics Toughened by Combining In Situ Growth Abnormal Grains, 3Y-TZP and Cu

Abstract

α-Al2O3 powders, a small amount of 3Y-TZP and Cu powders were used as principle materials in which adequate amount of TiO2-MgO-CAS system additives were added by wet grinding .The compacts were prepared by hot-pressed sintering. The results showed that the fracture toughness was significantly enhanced by synergistic toughening of in-situ growth abnormal grain, phase transformation and metal particles. Under the sinter condition of 30MPa and 1550 for 1h, the maximum fracture toughness reached to 7.90MPa·m1/2 and the bending strength is in advance of 600Mpa, which was one time higher than un-toughen alumina ceramics. The effects of multiphase synergistic toughening on the fracture toughness of alumina ceramic were investigated; meanwhile, the fracture behavior and the mechanisms of toughening were analyzed.