声发射检测灵敏度校准声源实验分析

在声发射技术的应用中,传感器的工作频率和灵敏度对AE检测的结果具有决定性的作用,传感器的校准是AE定量研究的基础,也是声发射检测技术研究中的重要课题。根据二级校准的相关要求设计了三个不同声源的实验:落球、断铅和压断毛细玻璃管法。通过重复性实验,测量了不同大小的钢球从不同高度下落;不同粗细、硬度以及不同长度的铅芯的断裂;不同粗细的毛细玻璃管被压断产生的脉冲声源,分别比较以上三个实验在不同状态条件下产生的脉冲声源信号,分析其实时特征和频谱特征(峰值,上升时间),通过计算确定其不确定度和稳定度,总结优化操作方法,同时分析了实验误差。在此基础上得出最适合做声发射传感器灵敏度校准的脉冲声源,为声发射传感器校准中的参考声源提供性能评判的依据。

Experimental analysis on sound sources of calibrating acoustic emission sensitivity

In the application of acoustic emission（AE）technology,operating frequency and sensitivity of sensor has a decisive role in the results of AE test,and AE Calibration serves as the basis for the calibration of quantitative research. In this paper,three different sound sources of experiment were designed according to secondary calibration of acoustic emission sensors：falling balls,pressuring off pencils and breaking the glass capillary. Through repeated experiments,firstly the pulse sound source signal generated by the three different experiments with different conditions were mersured,and the real-time features and spectral characteristics（peak value,rise time） were analyzed and compared. Then the most suitable pulse source in the emission sensor sensitivity calibration was determined,and the method of optimizing operation was summarized,so as to provide a basis for the evaluation of sound source signals in AE sensor calibration,Finally,the error during the experiment of acoustic emission sensors calibration was also addressed.