First Measurements from a New Broadband Vibrothermography Measurement System

We report on the construction and development of a broad‐spectrum vibrothermography (Sonic IR) measurement system at the Center for NDE. The new system uses a broadband actuator instead of an ultrasonic welder to generate vibration and induce heating of cracks. A high‐resolution infrared camera captures the IR signature of a crack, and a reconfigurable data acquisition software system acquires and processes the IR images and vibrometry waveforms in real time. We present and discuss results from initial experiments with this system, including the frequency dependence of vibrothermographic heating of flaws in a jet turbine stator vane and an analysis of the correlation of heating with vibration frequency in a cracked test specimen