Figure 3.16 shows the micro morphol

Figure 3.16 shows the micro morphology of the carbon fiber bridging, and the central bridging of the carbon fiber. When the carbon fiber with high aspect ratio is distributed evenly in zirconia matrix, the direction of the main crack propagation is easy to cross with the direction of carbon fiber. Usually, a bridge region composed of many fibers will be formed at the crack tip, which will produce bridging effect. The carbon fiber in the bridge region is perpendicular to the crack growth direction or at a certain angle. The carbon fiber connects the zirconia mechanism on both sides of the crack. When the crack needs to continue to expand, the carbon fiber will play an obstacle role, which will make the crack consume more energy during the process of crack growth. Because the bridge fiber in this area is the same thickness and fineness, it is the bridge in the middle of carbon fiber. When the middle part of carbon fiber acts as the bridging medium, it is shown that both sides of the bridge area on the carbon fiber are closely connected with the zirconia ceramic matrix. If the carbon fiber is pulled out or pulled out, more external load is needed to provide tensile stress, so the bridge joint in the middle of the fiber can greatly improve the fracture toughness of the material.