| In the rapid development of science and technology today, medical technology level also got rapid development, and promoted the ultrasonic diagnosis in medical field in occupied a very important position, but the development of science and technology do not stop the step, toward a more extensive space outspread, a higher technical level. The ultrasound medical development, can provide more accurate and more intuitive for ultrasound images, which can make better judgment, improve the medical technology. In the ultrasonic diagnostic equipment, ultrasonic transducer is its core part, its the role is to make the acoustic signal to electrical signal,or make electrical signal to electrical signal, the application principle is the material of transducer namely piezoelectric materials piezoelectric effect and converse piezoelectric effect.Piezoelectric materials research has developed to piezoelectric composite, made up of two main structure, there Main representative are 1-3 a piezoelectric composite, it can satisfy ultrasound diagnosis change to a broadband and pulse, high frequency and extreme, can design and study of theories and more mature. Piezoelectric ceramic although piezoelectric properties, but its hardness, brittle, making up very complex, and cannot bear too mechanical impact. Piezoelectric polymer can overcome the shortcomings of piezoelectric ceramic, its soft, can make into various materials, but the shape of piezoelectric coefficient and electromechanical coupling coefficient is not high, and the piezoelectric ceramic mechanical consumption is also big, this stimulated the people looking for new materials, and found that two kinds of materials according to certain way into composite materials, mixing preparation not only overcome the shortcomings of these two kinds of materials, but also inherited their advantages, thus become the research focus now piezoelectric materials. This paper studies the combined composite materials mainly composed for ferroelectric ceramics and polymer, its structure for ferroelectric ceramics with one-dimensional since even the ways in which the three-dimensional since polymers. On 1-3 piezoelectric materials with factors such as the following: the preparation methods and process of choice, the choice of materials, geometric shapes of piezoelectric phase in composite materials, in volume percentage, piezoelectric ceramic column height-width ratio, etc. The study on the properties of many methods, the most direct method for experimental method, namely, preparation, testing, sample results. This method, but the results have certain limitations, need to do lots of trial and error, and summarizes testing in the actual operation rule, this process may be due to the experimental condition, the influence of many factors, and the experimental results, the time will also need more. Finite element method can overcome these shortcomings, it can make the material properties and Settings for parameter form through the entity modeling analysis results, which not only can rule, provide theoretical basis for the experiment, and the choice of materials for transducer provides a direction.This subject mainly studies the application of ultrasonic transducer is mainly divided into five material chapter.(1) The first chapter for the introduction section, mainly introduce the research background and research topic, put forward the performance parameters of the piezoelectric composites.(2) Chapter 2, mainly talked about the structure and the form of ultrasonic diagnosis, and emphasized its core structure, for after study materials.(3) The third chapter undertake chapter two to introduces the content of materials about the transducer, summarized analysis method about 1-3 piezoelectric composites, put forward the finite element analysis.(4) The fourth chapter, analyzed according to the method of finite element research, and obtained the results.(5) Chapter 5 analyzed the results of the study, and discussed the future research... |
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