Simultaneous measurement of local longitudinal and transverse wave velocities, attenuation, density, and thickness of films by using point-focus ultrasonic spectroscopy
Simultaneous measurement of local longitudinal and transverse wave velocities, attenuation, density, and thickness of films by using point-focus ultrasonic spectroscopy
复制标题
使用点聚焦超声波光谱同时测量薄膜的局部纵波和横波速度、衰减、密度和厚度
DOI：
10.1063/1.4758136
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发表时间：
2012-10-15
影响因子：
3.2
通讯作者：
Chen, Jian
中科院分区：
文献类型：
--
作者：
Ju, Bing-Feng;Bai, Xiaolong;Chen, Jian
本文提出了一种超声技术，用于同时确定一套完整的声学和几何特性的薄膜或薄层中的分层材料嵌入两个已知的材料之间使用点聚焦超声光谱，它提供了一个高的横向分辨率。计算了分层材料的二维谱Rt（θ，ω）的理论模型，它是未知层的六个参数的函数：纵向和横向速度cl，ct，衰减αl，αt，密度ρ和厚度h，这六个参数完全决定了薄膜的性质。实验谱Re（θ，ω）可用V（z，t）技术测量。提出了一种两步算法，将参数搜索过程从一个六维空间分解到两个三维空间。研究了二维谱对单个性质的敏感性及其对实验噪声的稳定性。对250 μm厚的不锈钢膜和不锈钢膜的全套性能进行了测试。
This paper presents an ultrasonic technique for simultaneous determination of the complete set of acoustical and geometrical properties of a film or a thin layer in a stratified material embedded between two known materials using point-focus ultrasonic spectroscopy, which provides a high lateral resolution. The theoretical model of the two-dimensional spectrum Rt(θ,ω) of the stratified material is calculated as a function of six parameters of the unknown layer: longitudinal and transverse velocities cl, ct, attenuation αl, αt, density ρ, and thickness h, which fully determined the properties of the film. The experimental spectrum Re(θ,ω) can be measured by V(z,t) technique. A two-step algorithm is presented to decompose the searching process of parameters from one six-dimensional to two three-dimensional spaces. The sensitivity of the two-dimensional spectrum to individual properties and its stability against experimental noise are studied. The full set properties of a 250 μm thick stainless steel film an...