Critical role of carbon during production of ferroniobium alloy additions

In this contribution, both computational and experimental evidence is presented regarding the formation of niobium carbides during solidification of ferroalloys. In particular, the microstructures of solidified Fe–Nb–C melts with carbon concentrations varying from 0·1 to 0·7 wt-% are analysed and their phase portraits are compared with those predicted from the Scheil–Gulliver formalism. This investigation reveals that small changes of carbon …