Crack detection diagnostics using ultrasonic insonification and pattern recognition

Sudden crack growth has the potential to cause catastrophic failure when a crack reaches a critical crack size. Early detection of crack formation helps to minimize this potential. This research focuses on the use of guided ultrasonic waves (GUWs) to detect crack formation. Experiments are conducted on test specimens in which fatigue cracks are grown through cyclic loading. Macro Fiber Composite (MFC) and piezoelectric disc actuators are used as sensors to induce and receive various GUWs ranging in frequency from 25 to 100 kHz. Preliminary experimental results are given.