Abstract
With diversification of electronic components in recent years, many piezoelectric ceramics are used for the machine structure. However, the research in the past has put the accent on the improvement in the material characteristic, and the mechanical characteristic is not so clear. In this study, it evaluates near the fatigue crack using the nondestructive methods, the X-ray diffraction method and the atomic force microscope, it discussed about the effect of domain switching on the crack propagation by it. During the course of the applied load, the damage field is formed in the crack tip, and it was guessed that domain switching has had a great effect on the crack propagation process.