Characterization and Modeling of Precipitation Kinetics in a Fe-Si-Ti Alloy

In this article, we present a systematic study of precipitation kinetics in a Fe-Si-Ti alloy in the temperature range 723 K to 853 K (450 °C to 580 °C), combining complementary tools (transmission electron microscopy (TEM), atom probe tomography (APT), and small-angle neutron scattering (SANS)). We show that the Heusler phase Fe2SiTi dominates the precipitation process in the investigated time and temperature range, regardless of the details of the initial temperature history. A numerical model based on the evolution of precipitate size classes gives very good agreement with the experimental results, and its application to different alloy compositions provides directions for future alloy optimization.