Abstract: The present invention provides a thin sheet product having a combination of excellent magnetic properties inherent in the steel having a silicon content of 6.5% or near 6.5% with a further lowered iron loss property, particularly in a high frequency region, through the production of a magnetic thin steel sheet having a thickness of 0.23 mm or less by cold-rolling a steel sheet comprising by weight not more than that 0.006% of carbon, 5.0 to 7.1% of silicon, 0.07 to 0.30% of manganese, not more than 0.007% of sulfur, 0.006 to 0.038% of acid soluble aluminum and 8 to 30 ppm of total nitrogen with the balance consisting of iron and unavoidable impurities at a sheet temperature in the range of from 120.degree. to 350.degree. C. optionally after annealing the sheet at a temperature in the range of from 750.degree. to 1020.degree. C., and annealing the cold-rolled sheet at a temperature in the range of from 800.degree. to 1020.degree. C.

Abstract: Batch annealed, semi-processed and fully processed motor lamination steels are made by processes which subject a slab having an ultra low carbon composition (less than 0.01%) to at least the following steps: hot rolling with an austenite finishing temperature, coiling at a temperature ranging from 1300.degree.-1450.degree. F., and light temper rolling (less than 1.0% reduction) or leveling; reheating at a temperature less than 2300.degree. F., hot rolling with a ferrite finishing temperature, coiling at a temperature less than 1200.degree. F., and light temper rolling or leveling; or hot rolling with a ferrite finishing temperature, coiling at a temperature ranging from 1100.degree.-1350.degree. F. without a subsequent hot band anneal, and light temper rolling or leveling.

Abstract: Apparatus for effecting domain refinement of electrical steels comprises an assembly of an array of rotatable members (2) mounted within a supporting structure (3) and movable into direct contact with the surface of a strip or sheet of electrical steel to create lines of local plastic deformation which extends generally across the width of the steel to effect domain refinement thereof. Relative linear movement is imparted between the member and the steel strip or sheet.

Abstract: The present invention relates to the provision of a process for producing a grain oriented electrical steel sheet having excellent magnetic properties, and comprises heating a slab comprising by weight 0.021 to 0.075% of C, 2.5 to 4.5% of Si, 0.010 to 0.060% of acid sol. Al, 0.0030 to 0.0130% of N, 0.014% or less of (S and 0.405 Se) and 0.05 to 0.8% of Mn with the balance being Fe and unavoidable impurities to a temperature below 1280.degree. C. to hot-roll the slab, subjecting the hot rolled sheet to cold rolling with a draft of 80% or more and subjecting decarburization annealing and then finish annealing, characterized in that, after the hot rolling, the hot strip is taken up at a temperature of 600.degree. C. or below and subjected to nitriding at any stage from after the hot rolling to the completion of the secondary recrystallization in the finish annealing without annealing of the hot rolled sheet.

Abstract: A method and apparatus are provided for refining the domain wall spacing of a grain-oriented silicon steel strip by mechanical scribing and by employing more than one row of staggered small diameter scribing rolls arranged to scribe a different portion of the surface of the strip in a manner that the entire surface of the strip is scribed and in which each row of scribing rolls co-operate with an anvil roll to support the strip.

Abstract: A method and apparatus are provided for refining the domain wall spacing of a grain-oriented silicon steel sheet by mechanical scribing using a solid anvil roll and a scribing roller including scribing segments arranged side by side along an arbor. The arbor carries inflatable bladder ribs along the length of the arbor to provide uniform contact pressure exerted by scribing surfaces of the strip.

Abstract: In a production method for silicon steel hot rolled sheets by subjecting a slab of silicon steel to a rough hot rolling through high-temperature heating and then subjecting to a finish hot rolling, rolling at the first stand in the finish hot rolling is carried out so that a relation of thickness at entrance side of the stand t.sub.F1 (mm), thickness at delivery side thereof t.sub.F2 (mm), surface temperature of steel sheet at gripping T.sub.F0 (.degree. C.) and temperature at the depth of (t.sub.F1 -t.sub.F2)/2 (mm) from the surface of the steel sheet at gripping T.sub.F1 satisfies the following equation:(T.sub.F1 -T.sub.F0)/{(t.sub.F1 -t.sub.F2)/2}.ltoreq.10+t.sub.F1 /10 (.degree.C./mm).Thus, surface defect and surface cracks can be prevented in the hot rolling to provide silicon steel sheets having excellent surface properties.

Abstract: In the present invention, a slab of a silicon steel comprising usual components is hot-rolled while adjusting the hot rolling-finish temperature at 750.degree. to 1150.degree. C. and the cumulative reduction ratio of final three passes to at least 40%, or the above-mentioned silicon steel slab is hot-rolled at the above-mentioned hot rolling-finish temperature, the hot-rolled steel sheet is held at a temperature not lower than 35.degree. C. lower than the finish temperature for at least 1 second, and the steel sheet is wound at a winding temperature lower than 700.degree. C. Successively, the hot-rolled steel sheet is subjected, without annealing of the hot-rolled steel sheet, to cold rolling at a reduction ratio of at least 80%, decarburization annealing, and final finish annealing. According to this process, a grain oriented electrical steel sheet having superior magnetic properties can be prepared.

Abstract: In the present invention, grain oriented electrical steel sheets provided by heating a slab comprising, by weight percent, 0.025 to 0.075% of C, 3.4 to 5.0% of Si, 0.015 to 0.080% of sol. Al, 0.0030 to 0.013% of N, 0.014% or less of (S+0.405 Se) and 0.05 to 0.8% of Mn, sol. Al (%)/Si (%) being 0.0080 or more, the balance consisting of Fe and unavoidable impurities at a temperature below 1280.degree. C., hot-rolling the heated slab, subjecting the hot-rolled steel sheet to cold rolling, subjecting the cold-rolled steel sheet to decarbonization annealing with regulating the average diameter of primary recrystallized grains of the steel sheet subjected to decarbonization annealing to 18 to 35 .mu.

Abstract: A grain oriented electrical steel sheet having no significant glass film and having a high magnetic flux density and an excellent iron loss property, comprising, in terms of by weight, 2.5 to 4.5% of Si, the steel sheet having, as oxides on its surface, a glass film comprising 0.6 g/m.sup.2 or less in total of forsterite and spinel composed of MgO, SiO.sub.2 and Al.sub.2 O.sub.3 and an insulating coating having a thickness of 6 .mu.m or less, the face tension imparted on the surface of the steel sheet by the coating being in the range of from 0.5 to 2.0 kg/mm.sup.2. In the final box annealing of the steel sheet after primary recrystallization annealing, use is made of an annealing separator comprising 100 parts by weight of MgO and, added thereto, 2 to 30 parts by weight of at least one member selected from the group consisting of chlorides, carbonates, nitrates, sulfates and sulfides of Li, K, Bi, Na, Ba, Ca, Mg, Zn, Fe, Zr, Sr, Sn, Al, etc.

Abstract: The present invention provides a method of manufacturing a silicon steel sheet having grains precisely arranged in the Goss orientation, comprising the steps of preparing a steel material containing 0.01 wt % or less of C, 2.5 to 7.0 wt % of Si, 0.01 wt % or less of S, 0.01 wt % or less of Al, 0.01 wt % or less of N, subjecting the steel material to hot rolling maintained 1000.degree. C. or higher such that the temperature of the rolled material at an end of the hot rolling step falls within the range of 700.degree. to 950.degree. C., subjecting the steel material to a primary cold rolling process at a rolling reduction of 30 to 85%, annealing the steel material at a temperature of 600.degree. to 900.degree. C., subjecting the steel material to a secondary cold rolling process at a rolling reduction of 40 to 80%, annealing the steel material again at a temperature of 600.degree. to 900.degree. C.

Abstract: This invention lies in that a seed material controlled into a predetermined orientation is joined to a treating material under an activated state of joint face or through an interposition of an insert member and heated to a temperature causing grain boundary movement to render a whole of a joined body into a crystal body having a predetermined crystalline orientation. Furthermore, not only plate material and bar material but also coil can be used as the treating material, so that crystal bodies having excellent desired properties can be mass-produced with a good yield and in industrial scale.

Abstract: A process for producing a grain-oriented electrical steel sheet having a low watt loss, in which a steel strip consisting, in wt %, of 0.8 to 4.8 Si, 0.012 to 0.050 acid-soluble Al, 0.01 or less N, and the balance consisting of Fe and unavoidable impurities is cold-rolled to a final thickness of 0.15 mm or less, primary-recrystallization annealed, applied with a annealing separator containing magnesia as a major component by electrostatic spray painting, and then final-texture annealed.

Abstract: This invention is directed to improve magnetic properties and to stabilize the magnetic properties of a grain oriented electrical steel sheet used as a core of electric appliances. When producing a grain oriented electrical steel sheet by heating a slab containing C, Si, acid-soluble Al, N, not more than 0.014% of S+0.405 Se and 0.05 to 0.8% of Mn and the balance consisting of Fe and unavoidable impurities at a temperature of less than 1,280.degree. C.

Abstract: A process for manufacturing a high magnetic flux density grain oriented thin electrical steel sheet having superior magnetic properties and for use on transformers is disclosed. Proper amounts of Sn, Cr, Ni and Mo are added into a high magnetic flux density grain oriented electrical steel sheet in which AlN and MnS are utilized for inhibiting the growth of the primary recrystallization grains. The process results in the production of a high magnetic flux density grain oriented thin electrical steel sheet showing a stabilized recrystallization, a high productivity and a high yield.

Abstract: The present invention provides a steel composition and method for producing a high quality regular grain oriented electrical steel having less than 0.005% aluminum using a single cold reduction step. A high austenite volume fraction, the use of an annealing separator coating with high sulfur or a sulfur bearing atmosphere to provide strong surface energy grain growth, a quench after initial annealing to provide the optimum microstructure having a small amount of martensite with a fine carbide dispersion and various chemistry changes are included in the method. Excess manganese in combination with tin, which has been found to act similarly to excess Mn, are maintained at a total level less than 0.03%. The use of chromium in an amount ranging from 0.11% to 1.2% provides outstanding control of stability for secondary grain growth.

Abstract: A method of producing non-oriented electrical steel sheet comprising the steps of preparing steel comprising, by weight, up to 2.5% silicon, up to 1.0% aluminum and up to 2.5% (Si+2Al), with the remainder being iron and unavoidable impurities, hot rolling and cold rolling the steel to a final thickness and following this by finish annealing, wherein the average cooling rate between Ar.sub.3 and Ar.sub.1 during cooling transformation (.gamma..fwdarw..alpha.) of the steel is controlled to be 50.degree. C./s or less.

Abstract: Method for producing a magnetic steel strip having a thickness of less than 5 mm and containing, in composition by weight, more than 2% silicon, less than 0.1% carbon and a suitable amount of secondary recrystallization inhibiting elements, the balance being iron, obtained by a direct casting on one roll or between two rolls, characterized in that it comprises creating a crystallization structure comprising oriented grains {110} <001> in the skin, i.e. on the surface of a quench zone, by the sudden cooling of the steel in contact with the roll or rolls whose surface temperature is lower than 400.degree. C.

Abstract: A method of producing a non-oriented electromagnetic steel strip by subjecting a low-carbon steel slab to hot-rolling, cold rolling at a small reduction and first annealing. In order to improve magnetic flux density and surface appearance of the product, specific conditions are employed so as to coarsen the crystalline structure to obtain a controlled and moderate crystal grain size after the annealing. The slab is cold-rolled at a rolling reduction of about 5 to 15% and is subjected to first annealing by heating at a rate of about 3.degree. C./sec or higher and holding the strip for about 5 to 30 seconds at 850.degree. C. to the A.sub.3 transformation temperature of the steel, while controlling the crystal grain size to about 100 to 200 .mu.m after first annealing.

Abstract: A method of manufacturing a low-core-loss oriented electrical steel sheet. Thread-like grooves are formed in a cold-rolled grain oriented electrical steel sheet having a final thickness of about 0.27 mm or less in a direction within the range of about 30.degree. from the direction perpendicular to the rolling direction. The grooves and sheet satisfy the equationlog d.gtoreq.0.6 Ra+0.4where d is the groove depth (.mu.m), and Ra is the mean surface roughness of the steel sheet cold-rolled to final gauge. The steel sheet is thereafter decarburization annealed and final texture annealed.

Abstract: A grain oriented electrical steel having superior magnetic properties and for use in transformers and electrical generators, and a manufacturing process thereof are disclosed. Cu and P are mixedly added in the melting stage of a silicon steel containing MnS and AlN as grain growth inhibitors, and in this way, the magnetic properties are improved. The chemical composition of the steel sheet of the present invention are: 2.50-4.00% of Si, 0.03-0.15% of Mn, 0.030-0.300% of Cu, and 0.020-0.200% of P, the balance being Fe, all in weight %. The grain oriented electrical steel sheet of the present invention shows a low iron loss and a high magnetic flux density, and is cold-rolled to a thickness range of 0.15-0.27 mm.

Abstract: A grain oriented silicon steel strip and method are provided for producing the same wherein a chevron pattern of scribe lines mechanically refines the magnetic domain wall spacings. Multiple chevron patterns are formed to extend always transversely across the strip width.

Abstract: The present invention is a process for manufacturing a double oriented electrical steel sheet having a high magnetic flux density by carrying out a low temperature annealing for the secondary recrystallization by the use of AlN as inhibitor, characterized by hot-rolling a silicon steel slab comprising 1.8-4.8% by weight of Si, 0.008-0.048% by weight of acid soluble Al, 0.0028-0.0100% by weight of acid soluble Al, 0.0028-0.0100% by weight of total N, not more than 0.016% by weight of S and the balance being Fe and unavoidable impurities into a hot-rolled sheet, subjecting the sheet to cold-rolling at a reduction rate of 40-80%, subsequently subjecting the sheet to another cold-rolling at a reduction rate of 30-70% in the direction crossing the cold-rolled direction, annealing at 750.degree.-950.degree. C. in a wet hydrogen atmosphere for decarburization, and carrying out the final finishing annealing which comprises a stage for completing the secondary recrystallizing at a temperature of 920.degree.-1100.

Abstract: The present invention provides a method of manufacturing a silicon steel sheet having grains precisely arranged in the Goss orientation, comprising the steps of preparing a steel material containing 0.01 wt. % or less of C, 2.5 to 7.0 wt. % of Si, 0.01 wt. % or less of S, 0.01 wt. % or less of Al, 0.01 wt. % or less of N, subjecting the steel material to hot rolling maintained 1000.degree. C. or higher such that the temperature of the rolled material at an end of the hot rolling step falls within the range of 700 to 950.degree. C., subjecting the steel material to a primary cold rolling process at a rolling reduction of 30 to 85%, annealing the steel material at a temperature of 600.degree. to 900.degree. C., subjecting the steel material to a secondary cold rolling process at a rolling reduction of 40 to 80%, annealing the steel material again at a temperature of 600.degree.to 900.degree. C.

Abstract: A reaction gas or a gas containing a reaction gas is blown through blowing nozzles onto a steel material in a chemical vapor deposition treating chamber at a velocity sufficient to forcibly remove reacted products from reacted surfaces of a steel material while suppressing irregular thickness of a deposited film.

Abstract: A grain oriented silicon steel strip and method are provided for producing the same wherein a chevron pattern of scribe lines mechanically refines the magnetic domain wall spacings. Multiple chevron patterns are formed to extend always transversely across the strip width.

Abstract: The present invention provides a process for manufacturing a double oriented electrical steel sheet having a high flux density by suppressing the growth of the secondary recrystallization of {110} <uvw> oriented grains from the surface of the steel sheet in the hot-rolling stage or cold-rolling stage, which process comprises subjecting a hot rolled sheet comprised of 0.8-6.7% by weight of Si, 0.008-0.048% by weight of acid soluble Al, 0.

Abstract: A method of producing a grain oriented silicon steel sheet is adapted to lower the iron loss. A silicon steel slab, containing about 2.0 to 4.0 weight % of Si and an inhibitor-forming amount of S, or Se, or both, is hot rolled. After the hot rolled steel sheet is annealed when necessary, the steel sheet is cold rolled into a cold rolled steel sheet having a final thickness by performing cold rolling either one time or a plurality of times with intermediate annealing therebetween, the cold rolled steel sheet then being subjected to decarburization, coating of the surface of the steel sheet with an annealing separation agent mainly comprising MgO, secondary recrystallization annealing, and purification annealing. In the cold rolling step, an oxide layer exists on the surface of the steel sheet. Specifically, in the cold rolling step, rolling oil is supplied only at the entrance of the rolling mill used, and an oxide layer having a thickness of about 0.05 to 5 .mu.m is generated.

Abstract: A method of producing a grain oriented silicon steel thin sheet having excellent magnetic properties. A silicon steel slab containing Cu, Se and Sb as inhibitor-forming elements is hot rolled to form a hot-rolled sheet, followed by cold rolling at least twice including intermediate annealing to form a cold-rolled sheet having a final thickness of about 0.10 to 0.25 mm, decarburization and primary recrystallization annealing, and then final finish annealing. The temperature of the material to be rolled on the inlet side of the hot finish rolling mill is about 1000.degree. to 1150.degree. C. the surface temperature of the work rolls of the first stand of the hot finish rolling mill immediately before contact with the material to be rolled is about 100.degree. C. or less the total rolling reduction of the hot finish rolling is about 93 to 97%, the intermediate annealing is effected at a temperature of about 900.degree. to 1050.degree. C.

Abstract: A grain oriented silicon steel strip is flattened by a skin pass rolling to flatten undulations caused by scribe lines imparted to the strip for mechanically refining the magnetic domain wall spacings.

Abstract: An ultrahigh silicon, grain-oriented electrical steel sheet having a magnetic flux density, B.sub.8, of 1.57 or more and a degree of azimuth orientation, R (B.sub.8 /B.sub.s) of 0.87 or more is provided by cold-rolling an ultrahigh silicon steel sheet comprising by weight 0.005 to 0.023% of C, 5 to 7.1% of Si, 0.014% or less of S, 0.013 to 0.055% of acid soluble Al and 0.0095% or less of total N with the balance consisting of Fe and unavoidable impurities at a temperature in the range of from 120.degree. to 380.degree. C. optionally after annealing at a temperature in the range of from 800.degree. to 1100.degree. C.

Abstract: In grain oriented silicon steel sheets containing MnSe as a main inhibitor, an iron loss is reduced by increasing the magnetic flux density and realizing the thinning of product thickness and fine division of crystal grains while utilizing the stability of secondary recrystallization as a merit of such a sheet. In this case, 0.02-0.30% of Cu is added to a slab of the above grain oriented silicon steel, and particularly the decarburization annealing and/or the final finish annealing are carried out under particular conditions.

Abstract: A method of producing a low iron loss grain oriented silicon steel sheet which generates improved magnetostrictive characteristics when used as a stacked iron core and low noise when used in a stacked transformer, as well as superior shape characteristics. A grain oriented finish-annealed silicon steel sheet is coated with an insulating film. The surface of the grain oriented silicon steel sheet is irradiated with an electron beam along a multiplicity of spaced paths so as to refine the magnetic domains. The irradiation with the electron beam is conducted continuously or intermittently along a waveform path on the surface of the grain oriented silicon steel, and the wave-form, such as a zigzag form, has a period length much smaller than the width of the grain oriented silicon steel sheet, and line interconnecting the centers of successive waves extends substantially perpendicularly to the direction of rolling of the grain oriented silicon steel sheet.

Abstract: This invention not only improves the formation of fine crystal structure and hence the magnetic properties as well as surface properties while utilizing the merits of the hot strip mill at maximum by conducting the rough rolling in the steps for the production of grain oriented silicon steel sheets, particularly hot rolling step at a high temperature and a large draft, but also stably achieves the more improvement of the magnetic properties under a high reliability by accurately controlling the precipitation state of inhibitor at a finish rolling stage in the hot rolling step.

Abstract: The present invention produces a regular grain oriented electrical steel using a single cold reduction step having excellent and highly uniform magnetic quality. The method includes the steps of providing an electrical steel band having Mn of 0.024% or less in excess of that needed to combine with S and/or Se. The band is provided with an anneal at a temperature of from 900.degree.-1125.degree. C. (1650.degree.-2050.degree. F.) for a time up to 10 minutes and slowly cooled to 480.degree.-650.degree. C. (900.degree.-1200.degree. F.) followed by rapid cooling to a temperature below 100.degree. C. (212.degree. F.). The annealed band must have a critical amount of austenite, .gamma..sub.1150.degree. C., of 7% or more. The annealed band is cold reduced in a single stage to the desired final thickness. The strip is decarburized and provided with an annealing separator coating on one or more surfaces of the strip.

Abstract: The present invention relates to a process for preparing a metal sheet having an excellent rolling property, i.e., a rollable metal sheet, which process comprises the basic steps of: continuously feeding a molten metal on a cooling material having one or two cooling surfaces being transferred and renewed for quench solidification, to thereby prepare a thin cast sheet; impinging a small rigid body particle against the surface of the resultant thin cast sheet, to work the cast sheet; heat-annealing the worked sheet in such a manner that the worked region becomes a fine recrystallized grain layer; and subjecting the cast sheet to a cold or warm rolling, optionally after a removal of oxides present on the surface; and an optional step of heat-treating the rolled sheet for working. The process of the present invention is applicable to the production of various known rollable metal or alloy sheets, such as soft steel, stainless steel, silicon steel, nickel-iron, cobalt-iron, nickel, aluminum, and copper sheets.

Abstract: A decarburized steel sheet for a thin oriented silicon steel sheet having improved magnetic and coating characteristics and a method of producing the same. Silicon steel strip is hot-rolled, cold-rolled to a final thickness of about 0.28 mm or less, subjected to decarburization/primary-recrystallization annealing, coated with an annealing separator, and thereafter subjected to finishing annealing. In the decarburization/primary-recrystallization annealing step, a novel subscale is formed at the steel sheet surface having a fayalite-silica composition ratio in accordance with an infrared reflection absorbance ratio of about 0.5 to 5.5, and a marked oxygen amount of about 0.4 to 1.6 g/m.sup.2.

Abstract: A slab for an electrical steel sheet is heated at a temperature of 1280.degree. C. or below and then hot-rolled. The hot-rolled steel sheet or hot rolled and annealed steel sheet is then cold-rolled once or at least twice with intermediate annealing being performed between rollings. The cold-rolled sheet is decarburized and nitrided to form an inhibitor. The amount of nitrogen of in the steel sheet during the nitriding treatment subsequent to the decarburization annealing and the iron loss value after the withdrawal of the steel sheet from the furnace are measured to estimate the average diameter of a primary recrystallized grain, and next decarburization annealing is performed under conditions regulated in such a manner that the average diameter of the primary recrystallized grain of a product sheet falls within a proper range. The steel sheet subjected to the decarburization annealing is coated with an annealing separator composed mainly of MgO and then subjected to finish annealing.

Abstract: The present invention discloses a process for producing a grain-oriented electrical steel strip having a high magnetic flux density. The process comprises hot-rolling a steel ingot comprising basic ingredients and, added thereto, 0.02 to 0.15% of Sn at a temperature of 1200.degree. C. or below, annealing the hot-rolled strip, cold-rolling the annealed strip with a final rolling reduction of 80% or more and subjecting the cold-rolled strip to decarburization annealing, a nitriding treatment and finish annealing, wherein the temperature, T.degree.C., of annealing of the hot-rolled strip is set so as to fall within the range 1240-2.1.times.Al.sub.R <T<1310-1.8.times.Al.sub.R (wherein Al.sub.R =acid soluble [Al]-27/14.times.[N]) and the strip is soaked for 180 sec or less, maintained at a temperature in the range of from 800.degree. to 950.degree. C. for 30 to 300 sec and then quenched.The grain-oriented electrical steel strip thus produced is not influenced by the variation in the [Al] and [N].

Abstract: A silicon steel slab comprising 0.05 to 0.8% by weight of Mn and up to 0.014% by weight of S+0.405Se is heated at a temperature lower than 1280.degree. C. and hot-rolled under such conditions that the hot rolling-finish temperature is 700.degree. to 1150.degree. C., the cumulative reduction ratio at the final three passes is at least 40%, and the reduction ratio at the final pass is at least 20%, or this silicon steel slab is hot-rolled at a hot rolling-finish temperature of 750.degree. to 1150.degree. C. while adopting the above-mentioned reduction ratio according to need, is maintained at a temperature not lower than 700.degree. C. for at least 1 second, and wound at a winding temperature lower than 700.degree. C. The hot-rolled sheet is subjected to the hot-rolled sheet annealing, finally cold-rolled at a reduction ratio of at least 80%, subjected to the decarburization annealing, and then subjected to the final finish annealing.

Abstract: The present invention relates to a process for producing a non-oriented electromagnetic steel sheet having excellent magnetic properties after stress relief annealing, which comprises, after hot rolling or hot-rolled sheet annealing, subjecting a steel comprising, on the weight basis, 0.010% or less of carbon and from 4.0 to 8.0% of silicon with the balance consisting of Fe and unavoidable impurity elements, to cold-rolling at a rolling temperature in the range of from 100.degree. to 300.degree. C. once or at least twice with intermediate annealing, subjecting the cold-rolled sheet to continuous annealing, and further subjecting the annealed sheet to skin pass rolling with a reduction ratio in the range of from 2 to 15%. This process can provide a non-oriented electromagnetic steel sheet having excellent magnetic properties even when the stress relief annealing is conducted for a short period of time.

Abstract: An oriented silicon steel sheet with a very low core loss and a process for producing it at a lower cost are disclosed. The steel sheet consists essentially of Si: 1.5-3.0%, Mn: 1.0-3.0%, sol. Al: 0.003-0.015%, with Si (%)-0.5.times.Mn (%).ltoreq.2.0 and the balance being Fe and incidental impurities, in which the amount of C and N as impurities is not more than 0.0020%, with S being not more than 0.01%. This steel sheet can be produced from a slab containing up to 0.01% C and 0.001-0.010% N through hot rolling, cold rolling, primary and secondary recrystallization, and then decarburization.

Abstract: A method of manufacturing an oriented silicon steel sheet which achieves a high magnetic flux density while reducing the core loss. A silicon steel sheet containing Al and Sb as inhibitor components is cold-rolled once or a plurality of times. During cooling for annealing before final cold rolling, a small strain is created on the sheet and the temperature is within a certain range. Carbide precipitation is suitably controlled to precipitate carbides comparatively coarsely in grains.

Abstract: A method of primary recrystallization annealing grain-oriented electrical steel strip comprises the steps of conducting online measurement of the primary recrystallization grain diameter of the steel after primary recrystallization annealing and, based on the result of this measurement, controlling the primary recrystallization grain diameter of the steel after primary recrystallization annealing by varying either or both of the annealing temperature and the pass velocity during the primary recrystallization annealing. The method enables stable production of grain-oriented electrical steel strip exhibiting good secondary recrystallization and excellent electrical properties.

Abstract: This invention lies in that a seed material controlled into a predetermined orientation is joined to a treating material under an activated state of joint face or through an interposition of an insert member and heated to a temperature causing grain boundary movement to render a whole of a joined body into a crystal body having a predetermined crystalline orientation. Furthermore, not only plate material and bar material but also coil can be used as the treating material, so that crystal bodies having excellent desired properties can be mass-produced with a good yield and in industrial scale.

Abstract: It is a technical subject to advantageously avoid the degradation of surface properties in a low iron loss grain oriented silicon steel sheet as a material for transformers, particularly if it is intended to thin the gauge to 0.1.about.0.25 mm. A low iron loss grain oriented silicon steel thin sheet can stably be produced without causing the degradation of performances through strain relief annealing by considering a chemical composition in steel, optimizing the rolling conditions, particularly cold rolling conditions, and further forming heterogeneous microareas onto the steel sheet surface.

Abstract: A process for producing a grain-oriented electrical steel sheet having improved magnetic and surface film properties, comprising: using an electrical silicon steel slab containins S in an extremely small amount of 0.012 wt % or less and Mn in a limited range of 0.08 to 0.45 wt %; heating the slab to a relatively low temperature of not higher than 1200.degree. C.; hot-rolling the slab to form a hot-rolled strip; cold-rolling the strip to a thickness of a final product sheet; decarburization-annealing the cold-rolled strip; nitriding the strip while it is travelling; applying an annealing separator to the strip; and final texture-annealing the strip by heating the strip to a first temperature of from 800.degree. to 850.degree. C. in an atmosphere of (N.sub.2 +Ar).gtoreq.30 vol % with 25 vol % or more N.sub.2 and the remainder H.sub.2 and subsequently heating from the first temperature to above 1200.degree. C. in a conventional atmosphere.

Abstract: The present invention relates generally to a non-oriented electrical steel sheet usable as a metallic material for cores incorporated in an electrical apparatus, an electrical equipment or the like and the non-oriented electrical steel sheet is produced, by which a steel slab having a composition comprising Si: 0.1% or more but less than 1.5%, Al: 0.3% or more to 2.0% or less and Si+2Al: 2.0% or more is hot rolled; the hot-rolled steel plate is annealed at a temperature ranging from 1000.degree. to 1200.degree. C.; the annealed hot-rolled steel sheet is cold rolled at a reduction ratio ranging from 85 to 95%, and subsequently, the cold-rolled steel sheet is subjected to finish annealing under conditions of a temperature ranging from 750.degree. to 1000.degree. C. and a time longer than 15 seconds but shorter than 2 minutes.

Abstract: A process for producing a grain-oriented electrical steel sheet having a high magnetic flux density, comprising the steps of: heating a steel slab comprising 1.8 to 4.8 wt % Si, 0.012 to 0.050 wt % acid-soluble A1, 0.010 wt % or less N, and the balance consisting of Fe and unavoidable impurities, to a temperature for hot rolling; hot-rolling the heated slab to form a hot-rolled strip; cold-rolling the hot-rolled strip to a final product sheet thickness at a final cold rolling reduction of 80% or more by a single step of cold rolling or by two or more steps of cold rolling with an intermediate annealing step inserted therebetween; primary-recrystallization-annealing the cold-rolled strip; final-annealing the primary-recrystallization-annealed strip so that secondary-recrystallized grains substantially completely grow up in a temperature region of from 1000.degree. to 1100.degree. C. and then purification is effected above 1100.degree. C.

Abstract: A grain oriented silicon steel sheet having a low iron loss and not causing degradation of properties even through strain relief annealing is produced by applying ultrasonic vibrations to the surface of the sheet after secondary recrystallization annealing.