A thermoelectric method to detect weak local structural changes and inclusions in metal parts

The method is based on thermoelectricity. During the measurements, in the object to be measured a temperature gradient is generated which initiates the Seebeck electromotive force located in the defect region. It produces thermoelectric currents and, in turn, magnetic fields also outside the object. They are rather weak and most sensitive magnetometers are needed. We use a SQUID magnetometer system. The advantage of the method is the detectability of defects located deep inside parts.