RESUMEN
This paper is aimed to study the effect of notch's angle and depth on crack propagation of zirconia ceramics. We fabricated cuboid-shaped zirconia ceramics samples with the standard sizes of 4. 4 mm x 2. 2 mm x 18 mm for the experiments, divided the samples into 6 groups, and prepared notches on these samples with different angles and depth. We placed the samples with loads until they were broke, and observe the fracture curve of each sample. We then drew coordinates and described the points of the fracture curve under a microscope, and made curve fitting by the software-Origin. When the notch angle beta = 90 degrees, the crack propagation is pure type I; when beta = 60 degrees, the crack propagation is mainly type I; and when beta = 30 degrees, the crack propagation is a compound of type I and type III. With the increasing of the notch depth, the effect of notch angles on crack propagation increases. In addition, Notch angle is a very important fracture mechanics parameter for crack propagation of zirconia ceramics. With the increasing of notch depth, the impact of notch angle increases.