Application of Ultrasound Thermometry to Condition Monitoring of Heated Materials

Monitoring of thermal information of heated media is important for ensuring the reliability of high temperature processes in various industries. Ultrasound thermometry, which is a temperature measurement method by ultrasound, is expected as a potential candidate for such monitoring. In this work, an effective ultrasound thermometry utilizing both pulse-echo measurements and unsteady heat conduction analysis is applied to real-time monitoring of temperature profiles and heat fluxes of a heated steel. This method provides non-invasive measurements of such thermal information. To examine the feasibility of the method to condition monitoring, the internal temperature profile of a steel plate whose back surface is being heated, and cooled is monitored every 70 ms. Furthermore, the ultrasonic method is utilized to monitor heat fluxes of bonded materials of aluminum and copper, and reasonable results on transient variation in heat flux are then obtained. Thus, it is considered that the ultrasonic method could be applicable to condition monitoring of various heated materials.