摘要
利用有限元法(FEM)对板状材料中激光激发的超声导波进行了理论研究。考虑激光作用过程中材料热物理参数随温度变化的特性,用有限元方法数值模拟激光在板状材料中激发瞬态温度场,建立热弹机制下超声导波的产生和传播的有限元模型。在激光单脉冲能量不变的情况下,超声导波信号的峰值幅度随着脉冲激光的聚焦半径的减小则逐渐增大;同时缩小聚焦半径也可以提高超声导波的频带宽度。
This text utilizes the law of finite element （FEM） to carry on the theoretical research to the ultra acoustic conductance wave that the laser excited in the tabular material. Result of study indicate laser form pulse under the situation that energy does not change, ultra acoustic conducatance peak value range, wave of signal reduce and not crescent with focus radius, pulse of laser, Narrow at the same time and focus on the bandwidth that the radius can improve the ultra acoustic conductance wave too.
出处
《煤炭技术》
CAS
2005年第10期102-103,共2页
Coal Technology
关键词
激光超声
有限元法
超声导波
laser supersound
the law of finite element
exceed the acoustic conductance wave
