矩阵换能器超声三维成像方法研究*

针对常规超声检测难以直观地显示被检对象缺陷的形状及走向等问题,开展矩阵换能器超声三维成像方法研究。超声三维成像技术具有直观显示被测对象内部缺陷三维特征的优点,基于矩阵换能器的超声三维成像方法具有扫查速度快、分辨率高等优点,是当前超声三维成像技术的研究热点。本文介绍了矩阵换能器体扫查原理及其控制方法;提出了矩阵换能器体扫查时三维体数据采集方法和数据融合算法;基于矩阵换能器和相控阵板卡系统对铝标样等试样进行了体扫查检测实验,采用等值面和体绘制两种算法对缺陷进行三维成像,并对单一缺陷进行了定量分析,定量精度较高。研究结果表明,矩阵换能器超声三维成像方法能够表征缺陷的三维形貌特征,在无需移动换能器的情况下便可实现缺陷三维检测,是超声三维检测的有效方法。

Research on three dimensional imaging method using ultrasonic matrix array transducer

Aiming at the problems that conventional ultrasonic detection technology is difficult to directly display the shape and direction of the defect in the tested object and etc., three dimensional ultrasonic imaging method using matrix array transducer is studied. The three dimensional imaging ultrasonic technologies can directly display the 3D feature information of the defect inside the specimen, and can help to analyze the specimen. One of the technologies is based on ultrasonic matrix array transducer, which has the advantages of fast scanning speed and high 3D spatial resolution. The three dimensional imaging method based on ultrasonic matrix array transducer is introduced. Firstly, the volume scanning principle and the control method of the matrix array transducer, including calculating delay focusing law and ultrasonic field are introduced. Secondly, the 3D volume data collecting method and data fusion method are introduced. The volume scanning detection experiment on the aluminum specimen with flat bottom hole defect were conducted based on the matrix array transducer and phased array card system. The 3D imaging of the specimen defect was achieved with isosurface and volume rendering algorithms; the quantitative analysis of a single defect was conducted, and high accuracy was achieved. The study results show that the proposed three dimensional ultrasonic imaging method can exhibit the 3D shape characteristics of the specimen, and achieve the 3D test of the defect without requiring to move the transducer, which is an effective 3D ultrasound detection method.