PURPOSE: To product a high quality cast ingot without any shrinkage hole and segregation by successively widening the inner diameter at the side wall of a water cooled steel-made mold upward in arc-melting and casting method for Ni-Ti series alloy.
CONSTITUTION: The Nb-Ti series alloy bar material 6 is used as the anode and the water cooled steel-made mold 7 is used as the cathode and arc discharge is generated between the both and the alloy bar material 6 is continuously melted and this molten metal is dropped and cast into the water cooled steel- made mold 7. Then, by successively widening the inner diameter R at the side wall 1 in the water cooled steel-made mold 2 upward, air gap between the solidified body and the mold 2, developed by solidified shrinkage and heat shrinkage of the solidified body is narrowed while shifting the solidified body downward in the mold 2 by gravity and heat radiation to a mold from the solidified body is improved. Therefore, the solidified velocity is fast and the high quality cast ingot without defect, such as segregation, is obtd.
HIDENO AKIRA
SUZAI CHIKAHIRO
SUZUKI TAKUYA
