Passive Thermography Measurement of Damage Depth During Composites Load Testing

Passive thermography is commonly used for composites load testing to detect damage formation as a function of the applied load. The advantages passive are real time implementation, large area coverage, and noncontact measurement. able location size, however, depth has been challenge quasistatic loading. Recent work shown that during loading produces heating composed two heat generation components. first component an instantaneous thermal response due irreversible thermoelastic strain release rapid formation. second observed mechanical heating, at interface failure, fracture transient rise in surface temperature depth. defines start response. A one-dimensional model, independent delamination gap spacing, presented fitted data pixel by pixel, produce imagery percent difference between results, compared ultrasonic measurements length width, was on average 15%. X-ray CT 7%. This same processing technique detection cyclic well.