压电型声发射传感器的校准方法研究

项目名称： 压电型声发射传感器的校准方法研究

项目编号： No.51205378

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 机械工程学科

项目作者： 何龙标

作者单位： 中国计量科学研究院

项目金额： 25万元

中文摘要： 声发射检测在压力容器等大型结构件的状态监测中具有广泛的应用，压电型声发射换能器是声发射检测的重要部件，其灵敏度的准确校准是实现声发射定量技术的前提，而现有校准方法中的表面脉冲法和互易法所得的灵敏度数据存在较大差异，且电容传感器作为参考传感器，在制作和使用中存在诸多限制。本项目拟：1）引入激光多普勒测振技术实现微小动态位移的精确测量，通过研究脉冲力的大小和波形，优化载荷函数，将不同泊松比条件下Lamb问题中垂直点源问题的解析解与激光多普勒测量值相对照，获得准确的参考位移和参考速度。2）对表面脉冲法引入等效互易常数，即法向振动速度的频率分量与所加力脉冲的频率分量比值，与互易法中的互易常数进行比较，探讨其差异并研究如何修正。压电型声发射传感器校准方法的研究，有助于推进声发射定量技术的应用，完善垂直点源作用下Lamb问题解析解和声发射传感器的互易校准理论。

中文关键词： 声发射；传感器；校准；表面波；激光多普勒测振

英文摘要： Acoustic Emission (AE) technology has been applied widely in pressure vessels, aerospace engineering and other fields, and AE sensor is an indispensable component used to collect information in AE testing. Most AE sensors are piezoelectric transducers. The calibration of piezoelectric AE sensors is the premise of AE quantitative testing. The present research indicated that there were some difference between the sensitivity results calibrated by the surface pulse method and the reciprocity method suggested by the present standards. At the same time the reference capacitance sensor is difficult to develop and remain. This project is aiming to adopt the laser doppler technique to measure the micro-displacement of the medium.With the function modification of the pulse force,the comparison of analytic solution of the Lamb equation under the condition of different possion ratio with the laser measurement result is to be implemented, and the exact reference velocity is expected to be confirmed and used to do the AE sensor calibration. The surface pulse method and reciprocity method, as well as the Longitudinal wave reciprocity and optical method, will be compared with each other . The calculation result by the ratio of the frequency component of the normal velocity to the frequency component of the adding pulse force,

英文关键词： acoustic emission；sensor；calibration；surface wave；laser doppler vibration meter