A new and improved method for producing grain-oriented electrical steel sheet enabling production of grain-oriented electrical steel sheet realizing high magnetic flux density and excellent in magnetic characteristics, that is, as one aspect, a method for producing grain-oriented electrical steel sheet comprising a hot rolling process, cold rolling process, primary recrystallization annealing process, finish annealing process, and flattening annealing process, wherein shot blasting treatment and/or leveling treatment and treatment for contact with a solution are performed, the solution contains Cu etc. in a predetermined amount, the pH is −1.5 or more and less than 7, a solution temperature is 15° C. or more and 100° C. or less, and the time during which the steel sheet is dipped in the solution is 5 seconds or more and 200 seconds or less.

A non-oriented electrical steel sheet has a chemical composition containing, in terms of % by mass, C: 0.0015% or less and Si: 2.5 to 4.0% and having an average crystal grain size of 10 to 40 μm, and an internal oxidation layer having a thickness of 0.5 to 3.0 μm present in a sheet thickness direction of a surface thereof.

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° 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.

When a grain-oriented electrical steel sheet is produced by heating a steel slab containing, by mass %, C: 0.020 to 0.10%, Si: 2.0 to 4.0%, Mn: 0.005 to 0.50%, Al: less than 0.010%, N, S and Se: less than 0.0050% each to a temperature of not higher than 1280° C., subjecting slab to hot rolling, hot-band annealing, single cold rolling or two or more cold rollings having intermediate annealing between each cold rolling and a primary recrystallization annealing combined with decarburization annealing, applying annealing separator onto steel sheet surface, and subjecting steel sheet to finish annealing and a flattening annealing, a rapid cooling is conducted at an average cooling rate of not less than 200° C./s from 800° C. to 300° C. in cooling process from maximum achieving temperature in at least one of hot band annealing and intermediate annealing, whereby grain-oriented electrical steel sheet having excellent magnetic properties is stably produced.

The invention concerns a method for accentuating the orientation of the grains of a continuous steel sheet (1), in particular for producing electrical sheet steel, said method involving, during the movement of the steel sheet (1) in the longitudinal direction of same, a longitudinal stretching of the steel sheet (1) in a stretch region (1d) in which the steel sheet (1) moves at a temperature of between approximately 750° C. and approximately 900° C. The invention also concerns a device for implementing said method in which the stretching is carried out by two tensioning blocks (41, 42) comprising traction rollers arranged to move and guide the steel sheet (1). The invention further concerns a facility for producing electrical sheet steel comprising a line comprising a rolling mill and on which said method and said device are implemented downstream from the rolling mill.

By optimizing equipment and processing, magnetic domain miniaturization efficiency can be increased, workability can be improved, and processing ability can be increased through same. Provided is a method for miniaturizing the magnetic domains of a directional electric steel plate, the method comprising: a steel plate supporting roll position adjusting step of controlling the vertical direction position of a steel plate while supporting the steel plate progressing along a production line; and a laser emitting step of melting the steel plate by emitting a laser beam to form grooves on the surface of the steel plate, wherein the laser emitting step includes an angle changing step of changing an emitting line angle of the laser beam with respect to a width direction of the steel plate while an optical system emitting the laser beam onto the steel plate is rotated with respect to the steel plate, and a focal distance maintaining step of changing a tilt of the steel plate supporting roll which supports the steel plate according to a change in focal distance of the laser beam in the width direction of the steel plate.

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 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.

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.

A method for forming a film on a surface of a steel sheet includes applying a treatment solution for forming a film containing a fibrous material to the surface of the steel sheet by using a coater under a condition in which a difference between a speed of the steel sheet and a speed of an applicator of the coater is 1.0 m/min or more, inclining the surface of the steel sheet, to which the treatment solution for forming a film has been applied, at an angle of 10? or more with respect to a horizontal plane until drying is started, and thereafter drying the steel sheet.

A non-oriented electrical steel sheet of the present invention has a chemical composition capable of causing ?-? transformation, and contains 0.0005% to 0.0050% of Ti, in which, in a case where an area ratio of grains having a crystal orientation of an {hkl}<uvw> orientation (within a tolerance of 10?) when measured by EBSD is denoted as Ahkl-uvw, A411-011 is 15.0% or more, and the non-oriented electrical steel sheet has an average grain size of 10.0 ?m to 40.0 ?m.