超声相控线阵探头参数对波束形成的影响研究

Influence Study of Dimensional Parameters of Linear Phased Array Transducer on Beam Forming

超声探伤是工业中常用的一种无损检测方法,在实际探伤过程中,正确选择超声波探头参数对探伤效果十分明显,具有重要意义。以往为了表征探头特性,常引入探头参数对指向性的影响,但探头类型不尽相同,指向性函数的类型也有所不同。为减小主瓣宽度角,降低旁瓣幅度,保证探伤效果,文中基于波束形成算法理论,建立回波合成信号模型,优化参数使其简化,模型简单,通过仿真分析了不同超声相控线阵探头的阵元数、阵元间距、宽度以及探头频率对波束形成的影响并总结出规律,有助于选择探头参数,为超声相控线阵探头的设计提供了依据。

Ultrasonic flaw detection is a commonly used industrial non-destructive testing method. In the actual testing process, the correct choice of parameters on the ultrasonic probe is of key important. In the past, to characterize the probe character- istics, the directional effects on the probe parameters are often introduced. But the type of the probeis different, and types of diree- tivity function are different. In order to reduce side lobes, minimize the width of main lobe and ensure testing resuhs, based on algo- rithm theory, this paper established and simplified a simple synthetic echo signal model. The influence of different array element number, element spacing, element width and frequency of the probe on beam forming field produced by a linear phased array trans- ducer were systematically analyzed through the emulation mode. It can be used to guide the correct choice of parameters of the de- tection probe, thus providing the basis for the design of linear phased array transducer.