结合面参数的超声检测方法研究

Contact Parameter Estimation with Ultrasonic Method

为提高超声检测结合面参数的精度,有效去除超声探头聚焦区域的模糊效应,以球-板接触为例对超声检测结合面的方法进行了研究。利用聚焦超声探头扫描球-板接触区域得到了反射率矩阵,并对反射率矩阵进行误差估计,采用最小约束二乘滤波对反射率矩阵进行反卷积,结合构建的反射率-压力曲线,得到了球-板接触的名义接触区域及接触压力分布。利用商业有限元软件建立了球-板接触的有限元模型,以验证所提出的最小约束二乘滤波反卷积的有效性。研究结果表明,与现有维纳反卷积相比,采用最小约束二乘滤波反卷积得到的结合面接触压力分布与有限元模型结果更为吻合,能有效提高超声检测结合面参数的精度。

To improve accuracy of ultrasonic method for detecting joint parameters and remove the blurring effect from ultrasound focal zone, a new deconvolution approach is developed and a sphere plate contact is measured by ultrasonic method as an applying case. The ultrasound reflection map is obtained via scanning the joint surface by a focused ultrasound probe, the error of the ultrasound reflection map is estimated accurately, and the constrained least square filter is used for deconvolution of the reflection map, then the contact pressure is obtained with the reflection coefficient-pressure calibration curve. A finite element model of the sphere plate contact is established to verify the effectiveness. The results show that the contact pressure calculated by the proposed approach is in good agreement with the finite element model results, and is more accurate than that by the common deconvolution with Wiener filtering.