圆形钢板中声发射信号响应特征研究

声发射检测技术应用广泛，声发射仪器系统良好的灵敏度是进行声发射检测的重要保障。搭建了一套声源信号检测平台，通过实验和数值分析研究了两种不同声源在圆形钢板中声发射信号的响应特征。实验结果表明，随着与声源距离的增加，不同方向上信号的响应幅值变化趋势基本一致，不同方向间响应幅值的差异主要分布在2.1~8.8 dB。在距离声源0~350 mm时信号响应幅值整体下降速度较快，脉冲激励相较断铅激励产生的信号衰减率低 3% 左右。脉冲信号激励传感器产生的声源拥有更好的稳定性和再现性，本研究对声发射仪器灵敏度测试中声源的选择提供了参考。

Response characteristics of acoustic emission signal in round steel plate

The acoustic emission detection technology has used widely, and the good sensitivity of the acoustic emission instrument system is an important guarantee for the acoustic emission detection. In this paper, a set of sound source signal detection platform is built, and the response characteristics of acoustic emission signals of two different sound sources in a circular steel plate are studied through experiments and numerical analysis. The experimental results show that with the increase of the distance from the sound source, the variation trend of the response amplitude of the signal in different directions is basically the same, and the difference of the response amplitude between different directions is mainly distributed in 2.1~8.8 dB. When the distance from the sound source is 0~350 mm, the overall decrease of the signal response amplitude is faster, and the signal attenuation rate of the pulse excitation is about 3% lower than that of the lead-break excitation. The sound source generated by the pulse signal excitation sensor has better stability and reproducibility. This study provides a reference for the selection of the sound source in the sensitivity test of the acoustic emission instrument.