Spatially resolved acoustic spectroscopy for fast noncontact imaging of material microstructure.
Spatially resolved acoustic spectroscopy for fast noncontact imaging of material microstructure.
复制标题
用于材料微观结构快速非接触成像的空间分辨声波谱。
作者：
S. Sharples;M. Clark;M. Somekh
我们开发了一种非接触式、非破坏性技术，该技术使用激光产生和检测的表面声波来快速确定局部声速，以绘制多颗粒材料的微观结构。光学条纹以固定频率激发表面波，并且产生效率由条纹间距与激发区域中的声波波长匹配的紧密程度决定。钛合金的图像，使用该技术获得。讨论了提高目前0.8mm横向分辨率的方法，并实验证明了测量速度变化的能力，其精度为3300分之一。
We have developed a noncontact and nondestructive technique that uses laser-generated and detected surface acoustic waves to rapidly determine the local acoustic velocity, in order to map the microstructure of multi-grained materials. Optical fringes excite surface waves at a fixed frequency, and the generation efficiency is determined by how closely the fringe spacing matches the acoustic wavelength in the excitation region. Images of titanium alloys are presented, acquired using the technique. Methods to improve the current lateral resolution of 0.8mm are discussed, and the ability to measure velocity change to an accuracy of one part in 3300 is experimentally demonstrated.