Research And Implementation Of Ae Instrument Calibration System

In recent years, AE (acoustic emission) detection technology applieswidely in the fields of petrochemical, materials, aerospace, electrical,metalworking, transportation, etc. However, as the quality assurance, thecalibration of AE instrument did not form unified technical standards.Basing on this point, the paper establishes respectively calibration systemsof AE sensors and host instrument, and studies the consistency of differentcalibration systems of AE sensors, and explores the feasibility of usingelectrical signal to calibration host instruments. The main work includes:1. The paper sets up the calibration systems of the optical referencetransducer method and the reciprocity method of surface waves andlongitudinal waves, and analyzes the factors that affect the calibrationresults of the two methods from the definition of the sensitivity of thesensor. The paper chooses equipment used in the experiment throughanalyzing sound source, incentive transducer, the stimulus waveform,transmission media and couplant. It calculates the uncertainty ofreciprocity method and optical method with analyzing the sensor spacing,the physical parameters of the medium, current, voltage etc. The paperanalyzes various influencing factors in calibration system and provides a basis for the choice of the experimental apparatus and evaluation ofuncertainty.2. The calibration results of reciprocity method and optical method aswell as calibration results of surface waves and longitudinal waves arecompared. Different results of calibration methods show that thesensitivities of measurement by the two methods are similar in magnitudeand trend, but there are minor differences in some frequency. This articleanalyzes the difference on the number and phase changing. The calibrationresults of different acoustic modes will more different as the frequencyincreases. And it's relative with the frequency of sensor and SAW apertureeffect. The consistency of the results of reciprocity method and opticalmethod laid the foundation for the technical standards for uniformingacoustic emission calibration.3. Calibration program of several parameters (amplitude, rise time,duration, number of rings, the preamplifier gain) used commonly is given,the test result shows that the program is proper, and it can be used forcalibration services and engineering applications.