Non-Destructive Evaluation of Depth of Surface Cracks Using Ultrasonic Frequency Analysis

Sensors

Shiuh-Chuan Her¹ 

关键词: surface crack;    non-destructive evaluation;    ultrasonic;    Fourier transform;   

DOI  :  10.3390/s140917146

来源: mdpi

【 摘 要 】

Ultrasonic is one of the most common uses of a non-destructive evaluation method for crack detection and characterization. The effectiveness of the acoustic-ultrasound Structural Health Monitoring (SHM) technique for the determination of the depth of the surface crack was presented. A method for ultrasonic sizing of surface cracks combined with the time domain and frequency spectrum was adopted. The ultrasonic frequency spectrum was obtained by Fourier transform technique. A series of test specimens with various depths of surface crack ranging from 1 mm to 8 mm was fabricated. The depth of the surface crack was evaluated using the pulse-echo technique. In this work, three different longitudinal waves with frequencies of 2.25 MHz, 5 MHz and 10 MHz were employed to investigate the effect of frequency on the sizing detection of surface cracks. Reasonable accuracies were achieved with measurement errors less than 7%.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland.