Nippon Steel Sumitomo Metal Corporation

Nippon Steel Corporation

Yasuhiro Mayumi

Toshiya Takechi

Kenji Umetsu

Kazuhiko Fukutani

Tsutomu Ueki

Takashi Kataoka

Nobusato Morishige

Tomoya Suenaga

Haruhiko Atsumi

Atsushi Suzuki

Hideyuki Hamamura

Teruyuki Tamaki

Masamitsu Kubota

Naoto Masumitsu

Yohei Eguchi

Kazuya Tsurusaki

A method for manufacturing a grain-oriented electrical steel sheet according to an aspect of the present invention includes a step of obtaining a hot-rolled steel sheet by carrying out hot rolling on a slab containing a predetermined component composition with a remainder including Fe and impurities, a step of obtaining a hot-rolled annealed sheet by carrying out hot-rolled sheet annealing as necessary, a step of carrying out pickling to obtain a pickled sheet, a step of carrying out cold rolling to obtain a cold-rolled steel sheet, a step of carrying out primary recrystallization annealing, a step of applying an annealing separating agent including MgO to a surface and then carrying out final annealing to obtain a final-annealed sheet, and a step of applying an insulating coating and then carrying out flattening annealing.

Method for manufacturing grain-oriented electrical steel sheet and grain-oriented electrical steel sheet

A method for manufacturing a grain-oriented electrical steel sheet including a step of hot-rolling a slab containing a predetermined component composition with a remainder including Fe and an impurity to obtain a hot-rolled steel sheet, a step of, after carrying out hot-rolled steel sheet annealing on the hot-rolled steel sheet, carrying out cold rolling to obtain a cold-rolled steel sheet, a step of carrying out primary recrystallization annealing including a rapid temperature increase at an average temperature increase velocity V of 400&#xb0; C./s or more and imparting of a steel sheet tensile force S on the cold-rolled steel sheet, and a step of applying an annealing separating agent to a surface of the cold-rolled steel sheet after the primary recrystallization annealing and then carrying out flattening annealing.

Coil surfaces of a first coil () and a second coil () are parallel in a state of having an interval therebetween. When the first coil () rotates, a combined inductance by the first coil () and the second coil () changes.

Inductance adjusting device

The transverse flux induction heating device is allows an alternating magnetic field to intersect the sheet face of a conductive sheet which is conveyed in one direction, thereby inductively heating the conductive sheet. The transverse flux induction heating device includes a heating coil disposed such that a coil face faces the sheet face of the conductive sheet; a core around which the heating coil is coiled; a shielding plate formed of a conductor and disposed between the core and a side end portion in the direction perpendicular to a conveyance direction of the conductive sheet; and a non-conductivesoft magnetic material which is attached to the shielding plate, wherein the shielding plate is interposed between the core and the non-conductive soft magnetic material.

Transverse flux induction heating device

The transverse flux induction heating device is allows an alternating magnetic field to intersect the sheet face of a conductive sheet which is conveyed in one direction, thereby inductively heating the conductive sheet. The transverse flux induction heating device includes a heating coil disposed such that a coil face faces the sheet face of the conductive sheet; a core around which the heating coil is coiled; a shielding plate formed of a conductor and disposed between the core and a side end portion in the direction perpendicular to a conveyance direction of the conductive sheet; and a non-conductive soft magnetic material which is attached to the shielding plate, wherein the shielding plate is interposed between the core and the non-conductive soft magnetic material.

The transverse flux induction heating device allows an alternating magnetic field to intersect the sheet face of a conductive sheet which is conveyed in one direction, thereby inductively heating the conductive sheet. The transverse flux induction heating device includes a heating coil disposed such that a coil face faces the sheet face of the conductive sheet; a core around which the heating coil is coiled; and a shielding plate formed of a conductor and disposed between the core and a side end portion in a direction perpendicular to the conveyance direction of the conductive sheet, wherein the shielding plate has a protruded portion, and the side surface of the protruded portion represents a closed loop when viewed from a direction perpendicular to the coil face.

A control unit of an induction heating unit controls AC power output to a heating coil of a transverse type induction heating unit that allows an alternating magnetic field to intersect a sheet surface of a conductive sheet that is being conveyed to inductively heat the conductive sheet. The control unit includes: a magnetic energy recovery switch that outputs AC power to the heating coil; a frequency setting unit that sets an output frequency in response to at least one of the relative permeability, resistivity, and sheet thickness of the conductive sheet; and a gate control unit that controls a switching operation of the magnetic energy recovery switch on the basis of the output frequency set by the frequency setting unit.

Growing community of inventors

Tokyo, Japan

Yasuhiro Mayumi