Monitoring of directional solidification with simultaneous measurements of electrical resistance and temperature

In this paper, we present the efficiency of simultaneous electrical resistance and temperature (ERT) measurements for monitoring the position, X, and the growth rate, V, of the solidification front during the directional solidification of alloys. On a laboratory device for directional solidification (Bridgman-type furnace), the eutectic Pb–Sn alloy was solidified at five different pulling rates, VP, with a constant imposed temperature gradient, GP. During directional solidification, the electrical resistance and the temperature changes were measured simultaneously in the experimental samples. The results of the experiments show that simultaneous measurement of ERT enables not only the determination of the average growth rate, V, during directional solidification but also its fluctuation over the total measurement length of the sample.