Feasibility study on characterization of non-Gaussian rough surface by ultrasonic reflection method with the Kirchhoff theory
Feasibility study on characterization of non-Gaussian rough surface by ultrasonic reflection method with the Kirchhoff theory
复制标题
DOI：
10.1299/mej.16-00162
复制
发表时间：
2016-07
影响因子：
4.4
通讯作者：
M. N. F. Saniman;I. Ihara
中科院分区：
文献类型：
--
作者：
M. N. F. Saniman;I. Ihara
对材料非高斯粗糙表面的超声表征进行了基础性研究。在本研究中，推导了垂直入射时的超声反射系数、均方根粗糙度RQ和偏斜度RSK(衡量高度分布的对称性程度)之间的理论关系。在推导过程中，对粗糙表面的非高斯高度分布进行了有效的高斯曲线拟合，从而可以利用粗糙表面波散射的基尔霍夫理论。为了验证该关系式的有效性，在中心频率为0.35 MHz的正常入射配置下，对一系列具有不同RQ和RSK值的砂纸进行了空气耦合超声脉冲回波测量。根据测得的每一种砂纸的超声波反射系数，由推导出的与砂纸偏斜度的已知值的关系式估计了砂纸的RQ值，并与机械针式轮廓仪测量的值进行了比较。结果表明，超声波法和测针轮廓仪测得的RQ值基本吻合。从而证明了推导出的理论关系的正确性。
The fundamental study on the ultrasonic characterization of non-Gaussian rough surface of a material is carried out. In this study, a theoretical relationship among ultrasonic reflection coefficient at normal incidence, root mean square roughness Rq, and skewness Rsk (which is the measure of symmetrical level of a height distribution) has been derived. In the derivation, a Gaussian curve fitting to the non-Gaussian height distribution of a rough surface is effectively performed so that the Kirchhoff theory of wave scattering from a rough surface can be utilized. In order to verify the validity of the derived relationship, air-coupled ultrasonic pulse-echo measurements with normal incident configuration at center frequency of 0.35 MHz have been conducted to a series of sandpapers having various Rq and Rsk values. From the measured ultrasonic reflection coefficient of each sandpaper, the Rq values of the sandpapers have been estimated from the derived relationship with known values of skewness of the sandpapers and then compared to those measured by a mechanical stylus profiler. It is found that the Rq values estimated by the ultrasonic method and the stylus profiler almost agree with each other. Thus, the validity of the derived theoretical relationship is demonstrated.