Principal elements of cast iron, i.e. C, Si, Mn, P and S, have important effect on the quality and annealability of black heart malleable cast iron, and these elements are always controled in the manufacture of malleable cast iron. Besides these elements, raw materials of malleable cast iron i.e. foundry pig iron, steel scrap, return scrap and ferro-allays, contain various kind of tramp elements. The effect of these elements should not be neglected. In this report, influence of collective tramp elements on the graphitization of black heart malleable cast iron, was examined both in first stage and second stage annealing. Also individual effect of some tramp elements was examined.
