Abstract: A method for manufacturing a non-oriented electrical steel sheet including hot-rolling a steel slab containing 0-0.010% of C; at least one of Si and Al in a total amount of 0.03% to 0.5%; 0.5% or less of Mn; 0.10% or more to 0.26% or less of P; 0.015% or less of S; and 0.010% or less of N, on a mass percentage basis, the remainder being Fe and unavailable impurities, under conditions of a heating temperature in a single-phase austenite region and a coiling temperature of 650° C. or less; descaling the hot-rolled sheet to cold-roll the descaled sheet once or twice or more with an intermediate annealing sub-step therebetween; and then finish-annealing the cold-rolled sheet at a temperature of 700° C. or more in the single-phase ferrite region.

Abstract: A magnetic steel sheet with an insulating coating having a good punchability, high sliding performance, excellent handleability in processing, and good uniformity and adhesiveness is achieved by forming a chromium-free insulating coating containing 20 parts by mass or more and 90 parts by mass or less of fluorocarbon resin as a top layer coating of the magnetic steel sheet, and preferably making the kinetic friction coefficient of a surface of the insulating coating 0.3 or less.

Abstract: The present invention provides a non-oriented electrical steel sheet containing:

Abstract: A magnetic steel sheet with an insulating coating having a good punchability, high sliding performance, excellent handleability in processing, and good uniformity and adhesiveness is achieved by forming a chromium-free insulating coating containing 20 parts by mass or more and 90 parts by mass or less of fluorocarbon resin as a top layer coating of the magnetic steel sheet, and preferably making the kinetic friction coefficient of a surface of the insulating coating 0.3 or less.

Abstract: Grain-oriented silicon steel sheet with Bi as an auxiliary inhibitor and a forsterite coating film having a Cr spinel oxide subscale of FeCr2O4 or FexMn1-xCr2O4 (0.6≦x≦1), made from a steel slab containing 0.005-0.20 wt % of Bi and 0.1-1.0 wt % of Cr.

Abstract: A finish annealed non-oriented electromagnetic steel sheet includes about 0.01 wt % or less of C, greater than about 1.0 wt % and at most about 3.5 wt % of Si, at least about 0.6 wt % and at most about 3.0 wt % of Al, at least about 0.1 wt % and at most about 2.0 wt % of Mn, at least about 2 ppm and at most about 80 ppm of one or more rare earth metals (REM), a maximum content of Ti and Zr being about 15 ppm and 80 ppm, respectively, wherein oxygen on the surface layer of the steel sheet is 1.0 g/e2 or less. Since the non-oriented electromagnetic steel sheet has desirable mechanical properties resulting from the increased amounts of Si and Al, a high magnetic flux density can be maintained without sacrificing a punching property as well as very low iron loss can be obtained even after stress relief annealing.

Abstract: A finish annealed non-oriented electromagnetic steel sheet includes about 0.01 wt % or less of C, greater than about 1.0 wt % and at most about 3.5 wt % of Si, at least about 0.6 wt % and at most about 3.0 wt % of Al, at least about 0.1 wt % and at most about 2.0 wt % of Mn, at least about 2 ppm and at most about 80 ppm of one or more rare earth metals (REM), a maximum content of Ti and Zr being about 15 ppm and 80 ppm, respectively, wherein oxygen on the surface layer of the steel sheet is 1.0 g/m2 or less. Since the non-oriented electromagnetic steel sheet has desirable mechanical properties resulting from the increased amounts of Si and Al, a high magnetic flux density can be maintained without sacrificing a punching property as well as very low iron loss can be obtained even after stress relief annealing.

Abstract: Grain-oriented silicon steel sheet with Bi as an auxiliary inhibitor and a forsterite coating film having a Cr spinel oxide subscale of FeCr2O4 or FexMn1−xCr2O4 (0.6≦x≦1), made from a steel slab containing 0.005-0.20 wt % of Bi and 0.1-1.0 wt % of Cr.

Abstract: A grain-oriented electromagnetic steel sheet is provided which has a low ratio of iron loss in a weaker magnetic field to that in a stronger magnetic field and has special advantage in EI cores and the like. Also provided is a process for producing that steel sheet. The grain-oriented electromagnetic steel sheet is characterized in that its crystal grains of important components are specified in terms of their proportions in number, and the contents of Al, Ti and B, with a forsterite film formed on a surface of the steel sheet. In the process a low-Al silicon slab is heated at below 1,250° C. before hot rolling and the hot-rolled sheet is annealed with a temperature rise in the range of from 5 to 25° C./sec and at a temperature of from about 800 to 1,000 for a period of time of shorter than about 100 seconds.

Abstract: A finish annealed non-oriented electromagnetic steel sheet includes about 0.01 wt % or less of C, greater than about 1.0 wt % and at most about 3.5 wt % of Si, at least about 0.6 wt % and at most about 3.0 wt % of Al, at least about 0.1 wt % and at most about 2.0 wt % of Mn, at least about 2 ppm and at most about 80 ppm of one or more rare earth metals (REM), a maximum content of Ti and Zr being about 15 ppm and 80 ppm, respectively, wherein oxygen on the surface layer of the steel sheet is 1.0 g/m2 or less. Since the non-oriented electromagnetic steel sheet has desirable mechanical properties resulting from the increased amounts of Si and Al, a high magnetic flux density can be maintained without sacrificing a punching property as well as very low iron loss can be obtained even after stress relief annealing.

Abstract: Grain-oriented silicon steel sheet with Bi as an auxiliary inhibitor and a forsterite coating film having a Cr spinel oxide subscale of FeCr2O4 or FexMn1−xCr2O4 (0.6≦x≦1), made from a steel slab containing 0.005-0.20 wt % of Bi and 0.1-1.0 wt % of Cr.

Abstract: A method and a low iron loss grain-oriented electromagnetic steel sheet are disclosed. The method comprises the steps of: hot-rolling a grain-oriented electromagnetic steel sheet; cold-rolling the hot-rolled steel sheet once or twice intervened by intermediate annealing, so as to achieve the sheet thickness of a final product; annealing the cold-rolled steel sheet for decarburization; finish-annealing the decarburized steel sheet; forming linear grooves on the steel sheet substantially perpendicularly to the rolling direction, after the final cold-rolling step and before the finish-annealing step, by, for example, electrolytic etching or acid dipping; and filling the linear grooves with an element selected from the group consisting of Sn, B and Sb, or an oxide or a sulfate of an element selected therefrom.

Abstract: A grain-oriented electromagnetic steel sheet is provided which has a low ratio of iron loss in a weaker magnetic field to that in a stronger magnetic field and has special advantage in EI cores and the like. Also provided is a process for producing that steel sheet. The grain-oriented electromagnetic steel sheet is characterized in that its crystal grains of important components are specified in terms of their proportions in number, and the contents of Al, Ti and B, with a forsterite film formed on a surface of the steel sheet. In the process a low-Al silicon slab is heated at below 1,250.degree. C. before hot rolling and the hot-rolled sheet is annealed with a temperature rise in the range of from 5 to 25.degree. C./sec and at a temperature of from about 800 to 1,000 for a period of time of shorter than about 100 seconds.

Abstract: Production of grain-oriented silicon steel sheet, in which the heating temperature of slabs is as low as that in common steels and good magnetic properties are maintained, without applying a nitriding process. The contents of Al, Se and S substantially satisfy formulae (1) and (2), and both or either of formulae (3) and (4):?Al (wt %)!+(5/9){?Se (wt %)!+2.47?S(wt %)!}.ltoreq.0.027 (1)?Se (wt %)!+2.47?S (wt %)!.ltoreq.0.025 (2)0.016.ltoreq.?Al (wt %)!+(5/9){?Se (wt %)!+2.47 ?S (wt %)!}(3)0.010.ltoreq.?Al (wt %)! (4)Annealing of the hot rolling sheet is applied at a temperature of about 800.degree. C. or more, and about 1000.degree. C. or below; preferably, cold rolling is applied at about 100.degree. C. or more, using a tandem mill.

Abstract: A non-oriented silicon steel sheet having a low core loss contains Si in an amount of about 2.5-5.0 wt % and S restricted to about 0.003 wt % or less and inclusions; the volume ratio of those inclusions having a particle size of about 4 .mu.m or higher to the total volume of inclusions is about 5-60%, and the volume ratio of inclusions having a particle size less than about 1 .mu.m to the total volume of inclusions is about 1-15%; when the sheet contains Mn in an amount of about 0.4-1.5%, and the volume ratio of particles less than 1 .mu.m is about 1-5%, the silicon steel sheet also has a low rotation core loss.The method of manufacturing comprises controlling the change of a cooling speed to about 5.degree. C./s.sup.2 or less in the cooling process of such steel sheet in a finish annealing.

Abstract: A semi-process non-oriented electromagnetic steel strip having low core loss and high magnetic permeability is provided which consists essentially of, in % by weight, up to 0.02% of C, 0.2 to 2.0% of Si, 0.1 to 0.6% of Al, 0.02 to 0.10% of P, 0.5 to 1.5% of Mn, 0.1 to 1.0% of Ni, and optionally up to 0.6% of Cu, and optionally 0.01 to 0.2% of Sb and/or Sn, and a balance of iron and inevitable impurities. Magnetic properties are further improved when it is manufactured by hot rolling a slab having the composition at a temperature of from 1,100.degree. to 1,200.degree. C., completing hot finish rolling at a temperature of at least 700.degree. C. in the austenite region, annealing the strip at a temperature from 800.degree. to 880.degree. C. for at least one hour, cold rolling and annealing the strip, and optionally, skin pass rolling with a reduction of 2 to 12%.

Abstract: A semi-processed non-oriented electromagnetic steel strip having low core loss and high magnetic permeability is provided which consists essentially of, in % by weight, up to 0.02% of C, 0.2 to 2.0% of Si, 0.1 to 0.6% of Al, 0.02 to 0.10% of P, 0.5 to 1.5% of Mn, 0.1 to 1.0% of Ni, and optionally up to 0.6% of Cu, and optionally 0.01 to 0.2% of Sb and/or Sn, and a balance of iron and inevitable impurities. Magnetic properties are further improved when it is manufactured by hot rolling a slab having the composition at a temperature of from 1,100.degree. to 1,200.degree. C., completing hot finish rolling at a temperature of at least 700.degree. C. in the austenite region, annealing the strip at a temperature from 800.degree. to 880.degree. C. for at least one hour, cold rolling and annealing the strip, and optionally, skin pass rolling with a reduction of 2 to 12%.

Abstract: When producing a semi-process electromagnetic steel sheet by a series of process steps including cold rolling, annealing and skin pass rolling, in this order, a hot rolled sheet containing not more than 0.02 wt. % of C, 0.1 to 1.0 wt. % of Si, 0.5 to 1.5 wt. % of Mn, 0.1 to 0.6 wt. % of Al and 0.02 to 0.10 wt. % of P and optionally containing at least one of 0.1 to 1.0 wt.% of Ni, 0.01 to 0.2 wt. % in sum of Sb and/or Sn, and not more than 0.6 wt.

Abstract: A process and an apparatus for improving iron loss of electromagnetic steel sheet or amorphous material are disclosed. In this case, the steel sheet or amorphous material is subjected to an irradiation of plasma flame under specified conditions.

Abstract: A process and an apparatus for improving iron loss of electromagnetic steel sheet or amorphous material are disclosed. In this case, the steel sheet or amorphous material is subjected to an irradiation of plasma flame under specified conditions.