Temperature-dependent NDE of hydrided Zr-Nb tubing

The ultrasonic and thermal expansion characteristics of hydrided Zr-Nb tubing have been studied as a function of temperature. Changes in ultrasonic longitudinal velocity have been measured using a specially-designed high-temperature electromagnetic acoustic transducer in the through-thickness direction. In addition, dimensional changes have been monitored from within a tube using a capacitance technique, and compared to strain gauge data. In all cases, it has been confirmed that hydride concentrations can be estimated from a measurement of the terminal solid solubility temperature, leading to several possible methods whereby hydride concentrations may potentially be determined in situ.