The purpose of this work is to explore the capability of Fourier Thermal Analysis (FTA) to detect differences in solidification kinetics between unmodified and Sr modified eutectic Al-Si alloy obtained from the same base alloy. Experimental melts are produced in silicon carbide crucibles using an electrical resistance furnace and burdens of A356 alloy and commercial purity Si. The addition of strontium to the melts is accomplished using Al10 pct Sr master alloy rod. Chemical composition is controlled using spark emission spectrometry. The changes in microstructure are characterized using optical microscopy. Thermal analysis are performed in cylindrical stainless steel cups coated with a thin layer of boron nitride, using two type-K thermocouples connected to a data acquisition system. Experimental cooling curves are numerically processed using FTA. Results show changes in solidification kinetics of eutectic Al-Si alloy with different Sr content. These changes, measured at the beginning and during solidification of the probes, can be related to the changes in nucleation and growth causing the differences detected during microstructural characterization of the probes.
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