Effect of cerium on the as-cast microstructure and tensile ductility of the twin-roll casting Fe-6.5Â wt% Si alloy

Fe-6.5 wt% Si alloy doped with cerium is fabricated by twin-roll casting. Ce2O2S precipitates in the melt and acts as the efficient nucleation agent, leading to a refined solidification microstructure. The tensile ductility of this as-cast strip significantly reaches up to 56.8% at 600 °C, which is superior to the 22.8% of the as-cast strip undoped with cerium. The much more uniform and finer solidification microstructure along with the strengthened grain boundary is inferred to result in the dramatic improvement in tensile ductility.