Piezoelectric material has widely used in various applications with its high liable performance and quite smart electro-mechanical characteristics. However, solutions for number of troubles in strength and behavior of fracture have not sufficiently clarified yet. Among these associated solutions, the double torsion (DT) technique is the particular and effective method to measure toughness of fracture and growth behavior of slow crack in ceramic material. From the results of this work, it obtained the practical feasibility of the DT technique for finding growth behavior of crack initiated by kinds of cyclic electric fatigue on piezoelectric ceramics, and found that the initiated crack is able to propagate by using a relatively lower cyclical voltage than before cases under a constant mechanical load if the DT technique is used. In this study, it is also established the experimental method of the crack propagation by cyclic electric fatigue for the piezoelectric ceramics using DT technique, and found the possibility of the power law based on the classical Paris’ equation for analyzing the result of electric fatigue crack test.

压电材料以其高可靠性和相当灵巧的机电特性而广泛用于各种应用中。然而，关于强度和断裂行为的许多麻烦的解决方案尚未充分阐明。在这些相关解决方案中，双扭转（DT）技术是测量陶瓷材料的断裂韧性和慢速裂纹扩展行为的特殊而有效的方法。从这项工作的结果，它获得了DT技术的实际可行性，该技术可用于发现由压电陶瓷上的各种循环电疲劳引发的裂纹的生长行为，并发现通过使用相对较低的循环电压，该裂纹可以扩展。如果使用DT技术，则比在恒定机械负载下的情况要好。在这个研究中，