激光超声技术是一种非接触式的无损评估方法,其发展前景极为广阔。在本文中,用激光超声技术对牙齿进行检测。本文利用有限元方法对脉冲激光在健康牙齿中激发超声波的原理以及激光激发的超声波在健康牙齿中的温度变化和传播特性进行了理论分析,同时也对激光超声在初期龋齿中传播特性进行了理论研究。本文建立了相应的有限元模型,模拟声表面波在健康牙齿和初期龋齿中的激光热弹激发过程和传播过程并对其进行了数值模拟分析。本文的研究结果为激光超声对初期龋齿进行无损检测提供了理论依据。5374
关键词 激光超声 有限元方法 热弹机制 温度场 牙齿
毕业设计说明书(论文)外文摘要
Title Using the laser ultrasonic surface wave to research the character of human tooth
Abstract
Laser ultrasonic technology is a noncontact, nondestructive evaluation method, and its application scope is widely. In the paper, this method is effective for evaluating the properties of human tooth. By using the finite element method (FEM), laser-generated ultrasound thermoelastically in sound human dental enamel is studied, and using the same method, the propagation and the temperature change of laser ultrasonic wave in sound human dental enamel are also studied, as well as its propagation in early dental caries is also studied. In this paper, by using the finite element method(FEM), a theoretical model is established to simulate the laser thermo- elastic generation and propagation of surface acoustic wave(SAW) in sound human dental enamel and early dental caries, and its numerical simulation analysis is also studied. The conclusion in this paper may provide a theoretical basis for laser ultrasonic nondestructive evaluation of human tooth.
Keywords: Laser ultrasonics, Finite element method, Thermoelastic mechanism, Temperature field, tooth
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