キュポラ可鍛鑄鐵の改良に就て

抄録

The improvement on the cupola malleable iron was discussed by the duplex melting practice using 2t-cupola and 4t reverberatory furnace.
The molten metal in the cupola was transferred with its slag into the reverberatory furnace, the slag was skimmed off, and the melt was adjusted in its composition and deoxidized. In this practice the relation between the chemical composition of the slag formed in the cupola and the mechanical properties of the annealed products was examined.
When all the melting conditions except the blast-one were constant and the subsequent annealing cycle is also constant, the mechanical properties of the product were considerably influenced by the ratio CaO/SiO₂ of the cupola slag even if the chemical composition of the melt appeared constant.
When the ratio CaO/SiO₂ in the cupola slag was increased, the graphitization cycle could be shortened and the mechanical properties of annealed products are improved. To improve the properties of the products, the oxidation of molten iron in cupola must be avoided as much as possible and the superheating of melt in the forehearth (in this case reverberatory furnace) was absolutely needed.