C21D8/1222

NON-ORIENTED ELECTRICAL STEEL SHEET, METHOD FOR PRODUCING THE SAME, AND MOTOR CORE

Provided is a non-oriented electrical steel sheet having an average crystal grain size of crystal grains being not more than 80 μm, an area ratio of crystal grains having a grain size of not less than 1.5 times the average crystal grain size being not less than 10%; and an area ratio of crystal grains having aspect ratios of not more than 0.3 being not more than 20%, by subjecting a steel raw material containing, in mass %, C: not more than 0.005%, Si: 2.0 to 5.0%, Mn: 0.05 to 5.0%, Al: not more than 3.0%, and Zn: 0.0003 to 0.0050% to hot rolling, cold rolling, and cold-rolled sheet annealing and by heating the cold-rolled sheet to an annealing temperature between 700 to 850° C. at the average heating rate between 500 and 700° C. in a heating process of the cold-rolled sheet annealing to be not less than 10° C./s.

NON-ORIENTED ELECTRICAL STEEL SHEET

What is provided is a non-oriented electrical steel sheet having a chemical composition in which, by mass %, C: 0.010% or less, Si: 1.50% to 4.00%, sol. Al: 0.0001% to 1.0%, S: 0.010% or less, N: 0.010% or less, one or a plurality of elements selected from the group consisting of Mn, Ni, Co, Pt, Pb, Cu and Au: 2.50% to 5.00% in total are contained and a remainder includes Fe and impurities, in which a sheet thickness is 0.50 mm or less, and, in an arbitrary cross section, when an area ratio of {100} crystal grains is indicated by Sac, an area ratio of {110} crystal grains is indicated by Sag, and an area ratio of the {100} crystal grains in a region of up to 20% from a side where a KAM value is high is indicated by Sbc, Sac>Sbc>Sag and 0.05>Sag are satisfied.

ANNEALING SEPARATOR FOR ORIENTED ELECTRICAL STEEL SHEET, ORIENTED ELECTRICAL STEEL SHEET, AND MANUFACTURING METHOD OF ORIENTED ELECTRICAL STEEL SHEET
20230042915 · 2023-02-09 · ·

An annealing separator for an oriented electrical steel sheet including: a first component includes a Mg oxide or a Mg hydroxide; and a second component including one kind among oxides and hydroxides of a metal selected from Al, Ti, Cu, Cr, Ni, Ca, Zn, Na, K, Mo, In, Sb, Ba, Bi, and Mn, or two or more kinds thereof.

METHOD FOR MANUFACTURING A GRAIN-ORIENTED ELECTRICAL STEEL SHEET

Provided is a method for manufacturing a grain-oriented electrical steel sheet. A steel slab having a specific chemical composition is heated and hot rolled. A hot-rolled steel sheet thus obtained is subjected to hot band annealing to obtain a cold-rolled steel sheet, which is then subjected to primary recrystallization annealing to obtain a primary recrystallized steel sheet. An annealing separator is applied to the primary recrystallized steel sheet, which is then coiled. The coil is subjected to secondary recrystallization annealing to obtain a grain-oriented electrical steel sheet having an average value of a deviation angle (α.sup.2+β.sup.2).sup.1/2 calculated from a deviation angle α from ideal Goss orientation around an ND rotation axis and a deviation angle β from ideal Goss orientation around a TD rotation axis of 4.5° or less, and an area ratio R.sub.β of crystal grains with β≤0.50° of 15% or less.

Non-oriented electrical steel sheet and method for preparing same
11492678 · 2022-11-08 · ·

A non-oriented electrical steel sheet according to an exemplary embodiment of the present invention includes, by weight %, Si: 2.5 to 6.0%, Al: 0.2 to 3.5%, Mn: 0.2 to 4.5%, Cr: 0.01 to 0.2%, P: 0.005 to 0.08%, Mg: 0.0005 to 0.05%, and a remainder including Fe and inevitable impurities, while satisfying Equation 1 below, and formed with an inner oxidation layer of a 0.2 to 5 μm thickness inside a base steel sheet.
−2.5≤[P]/[Cr]−[Mg]×100≤6.5  [Equation 1]
(In Equation 1, [P], [Cr], and [Mg] respectively represent a content (by wt %) of P, Cr, and Mg).

Method for manufacturing a grain-oriented electrical steel sheet

Provided is a method for manufacturing a grain-oriented electrical steel sheet. The method comprises: hot rolling a slab to obtain a hot rolled sheet; subjecting the hot rolled sheet to hot band annealing as necessary; subjecting the hot rolled sheet to cold rolling; subjecting the cold rolled sheet to decarburization annealing; applying an annealing separator having MgO as a main component onto a surface of the decarburization annealed sheet and subjecting the decarburization annealed sheet to final annealing to form the forsterite film; and applying an insulating coating treatment liquid onto the final annealed sheet and subjecting the final annealed sheet to flattening annealing to form a tension-applying insulating coating. A difference in total tensions between one and opposite surfaces of the sheet is less than 0.5 MPa. A difference in tensions between the forsterite films in one and opposite surfaces of the sheet is 0.5 MPa or more.

GRAIN-ORIENTED ELECTRICAL STEEL SHEET AND METHOD FOR PRODUCING SAME
20230036436 · 2023-02-02 · ·

A grain-oriented electrical steel sheet according to an embodiment of the present invention may comprise: by weight %, 2.0-4.0% of Si, 0.04-0.2% of Mn, 0.010% or less (exclusive of 0%) of N, 0.01-0.05% of Sb, 0.005% or less (exclusive of 0%) of C, 0.03-0.08% of Sn, 0.01-0.2% of Cr, and the balance of Fe and inevitable impurities; and precipitates which have an average particle size of 5-50 nm and contain at least one of AIN, (Al, Si)N, (Al, Si, Mn)N, Mns, and CuS.

NON-ORIENTED ELECTRICAL STEEL SHEET AND MANUFACTURING METHOD THEREFOR
20230036214 · 2023-02-02 · ·

A non-oriented electrical steel sheet according to an embodiment of the present invention includes, in wt %, Si: 2.1 to 3.8%, Mn: 0.001 to 0.6%, Al: 0.001 to 0.6%, Bi: 0.0005 to 0.003%, and Ge: 0.0003 to 0.001%, and the balance of Fe and inevitable impurities.

Non-oriented electrical steel sheet and manufacturing method therefor
11486019 · 2022-11-01 · ·

The present invention relates to a non-oriented electrical steel sheet including 1.5 to 4.0 wt % of Si, 0.1 to 1.5 wt % of Al, 0.1 to 1.5 wt % of Mn, 0.005 wt % or less (excluding 0%) of C, 0.005 wt % or less (excluding 0%) of N, 0.005 wt % or less (excluding 0%) of Ti, 0.001 to 0.005 wt % of S, 0.1 wt % or less (excluding 0%) of P, 0.02 to 0.2 wt % of at least one of Sn and Sb, and a balance of Fe and other inevitable impurities; and satisfying the following Formulas 1, 2, and 3.
0.9≤[Al]+[Mn]≤2.1  [Formula 1]
0.2≤([Si]+[Al]+[Mn]/2)*([P]+[Sn]+[Sb])≤0.4  [Formula 2]
(Gs.sub.center−Gs.sub.surface)/(Gs.sub.center*t)≤0.5  [Formula 3] (In Formula 1 and Formula 2, [Al], [Mn], [Si], [P], [Sn], and [Sb] represent the content (weight %) of Al, Mn, Si, P, Sn, and Sb, respectively, and in Formula 3, t represents the thickness (mm) of the non-oriented electrical steel sheet, Gs.sub.surface represents the average grain size (μm) from 0 to t/4 or 3t/4 to t based on the thickness direction of the non-oriented steel sheet, Gs.sub.center represents the average grain size (μm) from more than t/4 to less than 3t/4 based on the thickness direction of the non-oriented steel sheet.)

METHOD FOR MANUFACTURING NON-ORIENTED ELECTRICAL STEEL SHEET

A method for manufacturing a non-oriented electrical steel sheet includes a step of obtaining a hot-rolled steel sheet by performing hot rolling on a steel material having a predetermined chemical composition, a step of performing first cold rolling on the hot-rolled steel sheet, and a step of performing first annealing after the first cold rolling. A final pass of finish rolling is performed in a temperature range equal to or higher than an Ar1 temperature, and cooling of which an average cooling rate is in a range of 50 to 500° C./sec is started in 0.1 sec from completion of rolling of the final pass of the finish rolling and is performed up to a temperature range higher than 250° C. and equal to or lower than 700° C.