AN APPLICATION OF INDUCTION-HEATING FOR FAST THERMAL NONDESTRUCTIVE EVALUATION

The application of induction heating as a selective heat source in a t hermal nondestructive evaluation system is described. The conductive p arts of the sample are heated with a scanning induction coil. Defects such as broken fibers or delaminations affect the heat flow in the sam ple and thus can be detected by monitoring the infrared radiation from the sample surface. In addition to thermal irregularities, the altere d electrical characteristics of the flaws also contribute to the signa l. Therefore, the detectability of the defects can be enhanced compare d to that of defects investigated using the traditional nonselective h eating methods. The functionality of the system is demonstrated with c arbon fiber reinforced composites.