高声衰减树脂基复合材料超声检测方法

ULTRASONIC TESTING METHOD OF HIGH SONIC ATTENUATION RESIN MATRIX COMPOSITE

根据高声衰减树脂基复合材料的特点,采用高能超声激励技术和接收端信号增强技术结合的穿透法对该种材料进行检测。分析了影响超声波幅值的激励电压、超声仪阻尼电阻、激励电信号波形等因素,提出了双极性方波脉冲串的激励方式,设计了接收端的放大电路,确定了检测参数。结果表明:在小于击穿电压的前提下,激励电压与超声波幅值成正比;其他条件不变,超声仪阻尼电阻调至最大时,可激励最大幅值的超声波信号;在同一条件下,不同激励电信号波形激励的超声波幅值大小关系为双极性方波脉冲串>单方波>尖脉冲;提出的方法实现了高声衰减树脂基复合材料的超声检测,且可检测不大于5mm的缺陷。

According to the characteristics of the resin matrix composites with high sonic attenuation,the high energy ultrasonic excitation technology and the signal enhancement technology of the receiving end are used to test the material.The excitation voltage,damping resistance and waveform of the excitation signal are analyzed,the excitation mode of bipolar square wave pulse string is put forward,the amplifier circuit of the receiving end is designed,and the testing parameters are determined.The results show that the excitation voltage is proportional to the ultrasonic amplitude when less than the breakdown voltage.When other conditions are unchanged,the ultrasonic signal with the largest amplitude can be excited when the damping resistance of the ultrasonic instrument is adjusted to the maximum.Under the same condition,the amplitude of ultrasonic wave excited by different waveform sequence from high to low is bipolar square pulse string,single square wave,sharp pulse.The proposed method can test the resin matrix composites with high sonic attenuation,as well as the defects not bigger than 5 mm.