摘要
基于超声波在层状介质中传播规律,建立理论声压透射系数Tp与材料弹性模量E的相关性.采用超声水浸技术测定微米厚薄板的双透射信号,通过信号分析获得实验声压透射系数Te,应用非线性最小二乘法反演薄板的弹性模量,并与声速法测量得到的弹性模量进行比较.结果表明:将反演的弹性模量代入到Tp中,发现在有效频带范围内Tp与Te吻合较好;反演获得的弹性模量值与声速法测定结果较接近,偏差介于1.4%和8.2%之间;实验证明了该方法可作为薄层材料弹性模量检测方法的一种补充.
The correlation between the acoustic pressure transmitting coefficient and elastic modulus of the material was established according to the law of ultrasonic wave propagating in the layered medium. The double-transmission signal was obtained by ultrasonic immerse-water technique and the acoustic pressure transmitting coefficient was measured by means of signal analysis. By the application of nonlinear least-squares optimization technique, the elastic modulus of the sheet metal was inversed and compared with those obtained by the velocity method. The results show that: theoretical values of the acoustic pressure transmitting coefficient are consistent with the experimental data, the values of elastic modulus obtained by the inversion method have a good agreement with the results of the velocity method, and the deviation lies between 1.4% and 8. 2%. Therefore, this method can be a supplement for the measurement of elastic modulus of lamellar materials.
出处
《测试技术学报》
2009年第2期106-111,共6页
Journal of Test and Measurement Technology
关键词
声压透射系数
弹性模量
非线性最小二乘法
反演
pressure transmitting coefficient
elastic modulus
nonlinear least-squares method
inversion
作者简介
付千发(1982-),男,硕士生,主要从事材料超声无损检测与评价研究通信作者:李萍(1969-),女,副教授,主要从事材料超声无损检测与评价研究.