压电膜片传感器的声发射特性研究

Study on Acoustic Emission Characteristics of Piezoelectric Film Sensor

现代自动化工业中,声发射传感器已被广泛应用于材料损伤监测,旧式商用声发射传感器因为结构脆弱,在实际应用中需直接粘于被测结构表面,导致二次利用率不高.为使所应用的监测系统效益比更高,本文提出一种采用压电隔膜作为敏感芯体的传感器结构.利用铅笔断裂法对其声学特性进行表征,测试结果显示,压电隔膜传感器和传统AE(声发射)商用传感器对信号的响应频率相关性最高可达到0.8以上.基于结果的良好相关性,可证明压电隔膜传感器具备结构简单、高效、耐用性高等优点,能够作为一种用于监测加工工艺过程的低成本替代方案.

In the modern automation industry,acoustic emission sensors have been widely used for material damage monitoring.The secondary utilization ratio of the old commercial acoustic emission sensor is low because of its fragile structure and its direct adhesion to the measured structure surface in practical application.To improve the efficiency of the monitoring system.This paper presents a sensor structure using piezoelectric membrane as sensitive core.The acoustic properties are characterized by a pencil crushing method and experimental results show that the Response frequency correlation of signals between Piezoelectric membrane sensor and conventional AE(acoustic emission)commercial sensor can reach a maximum of 0.8 or more.Based on the good correlation of the results,it can be demonstrated that the piezoelectric membrane sensor is a simple,efficient durable and low cost alternative for process monitoring.