Ultrasonic temperature determination during industrial materials processing

Two technologies for measuring temperature with ultrasound during the processing of materials are presented. Both methods use clad buffer rods. These approaches present the great interest of being able of providing, in addition to the temperature measurement, the simultaneous monitoring of other parameters of the material being processed such as its elastic properties. The first method uses clad buffer rods with two steps machined at the probing end contacting the material being processed. The ultrasonic time delays in the two regions which are between the rod end and the first step, and between the first and the second step can be calibrated versus temperature variation. The measurement of these time delays during material processing, associated with a conduction heat transfer model provide an accurate temperature at the probing end. For molten zinc processing at temperature ranging between 350 and 700 °C, good agreement was obtained between the temperatures measured ultrasonically and those measured by ...