By interaction between ultrasonic waves and elastic medium, it has carried much information of material, which are received in the form of ultrasonic echo signals.

• 它是利用超声换能器的振动产生的超声波与弹性介质相互作用,从而携带大量有关材料性能的信息,这种信息以超声回波信号的形式被接收到。