Interesting facts about Cerium in steel

Has a purifying action, as it deoxidizes pronouncedly and promotes desulphurization. It is frequently used in conjunction with lanthanum, neodymium, praseodymium and other rare earth metals as a composite metal. In high alloy steels, to some extent promotes hot forming properties and improves scale resistance in heat resisting steels. Fe-Ce alloys with approximately 70% Ce are pyrophoric (flint stones). Addition to spheroidal graphite cast iron.