Abstract: Disclosed is a continuous casting method in which a melt obtained by melting titanium or a titanium alloy is poured into a bottomless mold and is drawn downward while being solidified, wherein: the surface of the melt in the mold is heated by horizontally moving a plasma torch over the surface of the melt; thermocouples are provided at a plurality of locations along the circumferential direction of the mold; if the temperature of the mold measured by one of the thermocouples is lower than a target temperature, then the output of the plasma torch is increased when the plasma torch comes close to the location where that thermocouple is installed; and if said temperature is higher than the target temperature, then the output of the plasma torch is decreased when the plasma torch comes close to the location where that thermocouple is installed.

Abstract: A continuous casting method in which a molten metal obtained by melting titanium or a titanium alloy is injected into a bottomless mold having a rectangular cross-section and withdrawn downward while being caused to solidify, wherein a plasma torch (7) is caused to rotate in the horizontal direction above the surface of the molten metal (12) in the mold (2), and a horizontally rotating flow is generated by electromagnetic stirring on at least the surface of the molten metal (12) in the mold (2). It is thereby possible to cast a slab in which the casting surface condition is excellent.

Abstract: A continuous casting apparatus continuously casts an ingot formed of titanium or a titanium alloy. The apparatus includes a bottomless mold with a circular cross-sectional shape and a plasma torch. In the bottomless mold, a molten metal is poured from a top opening and the molten metal is solidified and the molten metal solidified is pulled out downward. The plasma torch is disposed on an upper side of the molten metal in the mold and generates a plasma arc that heats the molten metal. A plurality of plasma torches are disposed on the upper side of the molten metal in the mold. The plurality of plasma torches are moved in a horizontal direction above a melt surface of the molten metal along a trajectory keeping a distance not to allow for interference with each other.

Abstract: Provided is a device for titanium continuous casting (1) capable, even when continuously casting large diameter titanium ingots or titanium alloy ingots, of suppressing component segregation thereof. The device for titanium continuous casting (1) comprises: a mold (3) having an upper section having a circular upper opening (3a) for pouring in molten metal (6), and a bottom section having a lower opening for continuously drawing ingots (11); and a plurality of plasma torches (4, 5) to heat the molten metal in the mold (3) from the upper opening (3a) side. The plurality of plasma torches (4, 5) are disposed so that the amount of heat input to the molten metal (6) present in the outer circumference enclosing the center of the upper opening (3a) is greater than the amount of heat input to the molten metal (6) present in the center of the upper opening (3a).

Abstract: A continuous casting method in which a molten metal obtained by melting titanium or a titanium alloy is injected into a bottomless mold having a rectangular cross-section and withdrawn downward while being caused to solidify, wherein a plasma torch (7) is caused to rotate in the horizontal direction above the surface of the molten metal (12) in the mold (2), and a horizontally rotating flow is generated by electromagnetic stirring on at least the surface of the molten metal (12) in the mold (2). It is thereby possible to cast a slab in which the casting surface condition is excellent.

Abstract: Disclosed is a continuous casting method in which a melt obtained by melting titanium or a titanium alloy is poured into a bottomless mold and is drawn downward while being solidified, wherein: the surface of the melt in the mold is heated by horizontally moving a plasma torch over the surface of the melt; thermocouples are provided at a plurality of locations along the circumferential direction of the mold; if the temperature of the mold measured by one of the thermocouples is lower than a target temperature, then the output of the plasma torch is increased when the plasma torch comes close to the location where that thermocouple is installed; and if said temperature is higher than the target temperature, then the output of the plasma torch is decreased when the plasma torch comes close to the location where that thermocouple is installed.

Abstract: The continuous casting device according to the present invention enables at least some of a plurality of hearths (3) to be converted between being hearths (13) used for titanium, which are used during the continuous casting of titanium ingots, and being hearths (23) used for titanium alloy, which are used during the continuous casting of titanium alloy ingots. The number of hearths (23) used for titanium alloy is greater than the number of hearths (13) used for titanium. Also, the total capacity of the hearths (23) used for titanium alloy is greater than the total capacity of the hearths (13) used for titanium. Thus, titanium ingots and titanium alloy ingots can each be continuously cast by means of a single piece of equipment.

Abstract: A mold (2) has a cooling means (21) for having the thermal flux at four corner sections (2a) be smaller than the thermal flux at four face sections (2b). The cooling means (21) has first channels (22a) which are each embedded in the four corner sections (2a) respectively and which channel cooling water, and second channels (22b) which are each embedded in the four face sections (2b) respectively and which channel cooling water. The distance from the inner peripheral surface of the mold (2) to the first channels (22a) is greater than the distance from the inner peripheral surface of the mold (2) to the second channels (22b).

Abstract: By controlling the temperature (TS) of a surface portion (11a) of an ingot (11) in a contact region (16) between a mold (2) and the ingot (11) and/or a passing heat flux (q) from the surface portion (11a) of the ingot (11) to the mold (2) in the contact region (16), the thickness (D) in the contact region (16) of a solidified shell (13) obtained by the solidification of molten metal (12) is brought into a predetermined range. Consequently an ingot having a good casting surface state can be cast.

Abstract: In a mold designing, a deformation amount of a casting from a solidification start time to a cooling end time may be obtained by deformation analysis software, and a deformation amount of a mold from a pouring time to the solidification start time may be obtained by deformation analysis software. When a cavity shape is designed based on the obtained deformation amounts of the mold and the casting, the precision of a near net shape may be further improved by reflecting the mold cavity shape at the solidification start time to the mold design, and a lack in dimension of a casting product after the casting process may be prevented.

Abstract: A mold (2) has a cooling means (21) for having the thermal flux at four corner sections (2a) be smaller than the thermal flux at four face sections (2b). The cooling means (21) has first channels (22a) which are each embedded in the four corner sections (2a) respectively and which channel cooling water, and second channels (22b) which are each embedded in the four face sections (2b) respectively and which channel cooling water. The distance from the inner peripheral surface of the mold (2) to the first channels (22a) is greater than the distance from the inner peripheral surface of the mold (2) to the second channels (22b).

Abstract: The continuous casting device according to the present invention enables at least some of a plurality of hearths (3) to be converted between being hearths (13) used for titanium, which are used during the continuous casting of titanium ingots, and being hearths (23) used for titanium alloy, which are used during the continuous casting of titanium alloy ingots. The number of hearths (23) used for titanium alloy is greater than the number of hearths (13) used for titanium. Also, the total capacity of the hearths (23) used for titanium alloy is greater than the total capacity of the hearths (13) used for titanium. Thus, titanium ingots and titanium alloy ingots can each be continuously cast by means of a single piece of equipment.

Abstract: Using plasma arcs generated by plasma torches, the surface of molten metal charged into a mold is heated. EMSs arranged on the lateral sides of the mold are used to stir the surface of the molten metal or the vicinity thereof electromagnetically. Thus, a slab having reduced defects can be cast.