Abstract
In the previous paper, the change in the characteristics of Mg-treated spheroidal graphite iron caused by remelting was described in details. It was ascertained that the change occurred, keeping some relationship with the decrease in residual Mg content. Hence the change due to remelting should be deemed to originate in the behavior of residual Mg in molten iron remelted. In the present paper, some considerations were given to the relationship between the change in the characteristics caused by remelting and the behavior of residual Mg from the standpoint of the mechanism of spheroidal graphite formation due to Mg treatment. The results seemed to suggest that the effective state of residual Mg in spheroidal graphite iron may be found as an active state in the spheroidal graphite domain.
