Abstract
To investigate the casting defects caused by the gases in molten iron, we added K3Fe(CN)6, Fe2O3, SiO2, Fe-Si and Al to the molten iron, which was poured in the special and the balanceweight type specimens.
Nitrogen contents were increased by addition of K3Fe(CN)6 and oxygen contents were increased by addition of Fe2O3 or SiO2.
Cast specimens of eutectic irons to which were added K3Fe(CN)6, showed special defects, and cast specimens of hypo-eutectic irons added K3Fe(CN)6. showed many small blow-holes. However cast specimens of eutectic and hypo-eutectic irons added Fe2O3 or SiO2, had no defects.
Further, special defects were increased by addition of ferro-silicon and decreased by addition of Aluminum.
From these results, it was shown that nitrogen in molten iron produced casting defects, having different features depending on the chemical composition of the metal.
