Role of silicon on oxide morphology and pickling behaviour of automotive steels

The present study investigates the effect of Si on the oxide morphology and picklability of automotive steels. It was observed that in steels containing high levels of Si, Si exists as a non-stoichiometric fayalite (Fe2.44Si0.55O4) phase, and such a phase is not easily picklable. It was also noted that as the amount of Si increases, the pickling kinetics becomes slower. Hence the amount of Si should be kept low for automotive and other applications where a surface finish is required.