Phase transition kinetics in spheroidal graphite irons.

We plan to measure in-situ liquid-solid and solid-solid phase transitions in Fe-Si-C-alloys in the proposed experiment. One objective is to determine the undercooling for γ-Fe and graphite nucleation as a function of alloy composition and inoculation by ceramic microparticles, previously evaluated in SEM and TEM (see Figure 1). Also, the kinetics of the eutectic and eutectoid transitions will be recorded at fixed cooling rates as a function of crystallographic change: amorphous to γ-Fe in the eutectic (~1150 °C), and γ-Fe to α-Fe (~800 °C) in the eutectoid.