Study On The Preparation And Properties Measuring Of The Piezoelectric Ceramic Fiber

With the development of piezoelectric materials research, the performance of 1-3 piezoelectric fiber composites is more and more important. Especially after the orthotropic characteristics ability of the 1-3 piezoelectric fiber composites has been developed, it has more potential applications in sensing and driving field. There are reasons of two aspects that affect the performance of 1-3 piezoelectric fiber composites . First, the performance of the polymer is used for making composite materials; second, the performance of the piezoelectric fibers. If, in the same conditions, the better the performance of piezoelectric fiber, the better their final performance. So, the performance of piezoelectric fiber plays an important role in 1-3 piezoelectric fiber composites. Seeking for the better performance of the piezoelectric fiber is the focus of current research. At the same time, how to measure the piezoelectric properties of the latest piezoelectric fiber has become an important issue in the course of research and production . Because of these problems, the specific content of this thesis has the following components:First, there are two different methods to prepare piezoelectric ceramic fibers. One is prepared by extrusion process, the other is the activated carbon template method to produce ceramic fibers. Used the extrusion process method as the main preparation methods, the types of piezoelectric ceramic fibers have a diameter of 250μm, length of the 150mm and good piezoelectric properties. The diameter of piezoelectric ceramic fibers prepared by the activated carbon template method is much smaller than prepared by extrusion process, only the 25μm, and the fiber surface is smooth, straight fibers can automatically into the beam. This preparation method has high potential value to study.Second, A piezoelectric properties measure method of minor diameter piezoelectric ceramic fiber has been developed. The basic theory of piezoelectric materials has been introduced, the performance characteristics of piezoelectric ceramic fibers and 1-3 piezoelectric composite materials have been analyzed, and several measurement methods of piezoelectric constants are analyzed. All of these provide theory basis for measuring the piezoelectric constants of piezoelectric ceramic fibers. Basing on 1-3 piezoelectric fiber composites micromechanics model of uniform field theory, a new type of piezoelectric ceramic fibers measuring piezoelectric stress constants method has been designed. Through simulation analysis, parameters of the key structure of the measurement method has been analyzed, and the measurement requirements of the test conditions have been obtained.Third, prepared 1-3 piezoelectric fiber composites specimens using the ceramic fibers obtained by extrusion process and measured its piezoelectric stress constants. The measurement results shows that this measurement method is feasible and the piezoelectric ceramic fibers obtained by extrusion process have good piezoelectric properties.