Abstract: Grain oriented silicon steel sheet on which is formed an insulating coating having a thickness that is not less than 2.5 .mu.m that imparts tension to the steel sheet which does not have an inorganic mineral layer formed during a final annealing step (glass film) and a method of forming on grain oriented silicon steel sheet an insulating coating that is not less than 2.5 .mu.m thick and which imparts tension to the steel sheet which does not have the inorganic mineral layer (glass film) that forms during finish annealing, and a method of forming a tensioning insulating coating on grain oriented silicon steel sheet which has been finish annealed and does not have an inorganic mineral surface layer (glass film), after first forming a layer of SiO.sub.2 not less than 0.001 .mu.m thick on the oriented silicon steel sheet.

Abstract: A stainless steel alloy useful as a construction material in superconducting magnetic components, said alloy containing in weight percent 0.05-0.25% C, 0.1-1.5% Si, 3.5-7.5% Mn, 17-21% Cr, 6-10% Ni, 0.10-0.50% N, the remainder being Fe and normal impurities.

Abstract: A silicon steel sheet contains 0.01 wt. % or less C, 4 to 10 wt. % Si, 0.5 wt. % or less Mn, 0.01 wt. % or less P, 0.01 wt. % or less S, 0.2 wt. % or less sol. Al, 0.01 wt. % or less N, 0.02 wt. % or less 0 and the balance being Fe. The silicon steel sheet has grain boundaries and carbides which are precipitated on the grain boundaries. The carbides have an area of 20% or less to an area of the grain boundaries. The steel sheet is cooled at a cooling speed of 5.degree. C./sec. or more in a temperature range of from 300 to 700.degree. C.

Abstract: In a process for the preparation of oriented electrical steel sheet having a high magnetic flux density a primary recrystallization annealed steel sheet is nitrided for a short period of time in a temperature range of 800.degree. C. or less whereby growth of crystal grains does not substantially occur. The nitrided sheet is held at a temperature range of 700.degree. C. to 800.degree. C. for at least four hours during temperature raising to final annealing temperature whereby nitride formed by the nitriding dissolves and re-precipitates allowing the nitride to transform to a thermally stable nitride containing aluminium.

Abstract: A method of producing a grain-oriented magnetic steel sheet exhibiting a very low core loss and high magnetic flux density uses a slab of silicon steel containing Al, B, N, and S and/or Se. The method employs hot rolling conducted such that the rolling reduction falls within the range of from about 85 to 99%, and the hot-rolling finish temperature falls within the range of from 950.degree. to 1150.degree. C. and is based on the contents of Si, Al and B. The hot-rolled steel sheet is rapidly cooled at a cooling rate of about 20.degree. C./s and is coiled at a temperature of about 670.degree. C. or lower. Hot-rolled sheet annealing or intermediate annealing is executed by heating the hot-rolled steel sheet up to about 800.degree. C. at a heating rate of from 5.degree. to 25.degree. C./s and holding at a temperature of from about 800.degree. to 1125.degree. C. for a period not longer than about 150 seconds.

Abstract: The invention comprises a method for producing electric sheets, in particular grain-oriented electric sheets, with an evenly well-adhering glass film and with improved magnetic properties, in which the hot rolled strip which is produced at first and is optionally annealed is cold-rolled up to an end thickness in one or several steps, thereafter an annealing separator is applied to the strip which is rolled up to the end thickness, and is dried, and therafter the cold strip thus coated is subjected to high-temperature annealing, with an important component of the annealing separator being a hydrous magnesium oxide (MgO) dispersion and the annealing separator being additionally provided with at least one additive. The characterizing feature of the invention is that a finely dispersed water-soluble sodium phosphate compound is used as at least one additive.

Abstract: Grain-oriented electrical steel sheet having a very low iron loss with controlled area ratio of fine grains, average grain size of coarse grains, obliquity of the grain boundary line of coarse grains, permeability under 1.0 T, and film tension.

Abstract: A process for producing a grain-oriented electrical steel sheet excellent in the glass film and the magnetic properties by coating a steel sheet with an annealing separator, finish annealing the steel sheet, and baking an insulating coating agent, which comprises coating the steel sheet having been decarburization annealed with an annealing separator prepared by allowing 100 parts by weight of MgO to contain, in the course from the step of producing MgO to the stage of preparing a slurry in the step of coating the steel sheet with MgO, halogens selected from F, Cl, Br and I or compounds of the halogens in an amount of 0.015 to 0.120 part by weight in terms of F, Cl, Br and I, and finish annealing the steel sheet.

Abstract: A method of producing a grain-oriented electrical steel sheet with a very low core loss comprises the steps of obtaining a rolled strip of final product thickness using as a starting material molten steel consisting of not more than 0.10 wt % C, 2.5-7.0 wt % Si, ordinary inhibitor components and the balance of iron and unavoidable impurities, heating the strip to a temperature range of not less than 700.degree. C. at a heating rate of not less than 80.degree. C./s and within 0.1 second after the maximum temperature has been reached cooling the strip at a cooling rate of not less than 50.degree. C./s, and subjecting the strip to decarburization annealing and final finish annealing.

Abstract: A method of effectively manufacturing silicon steel sheets with highly accumulated {100} orientations having excellent magnetic characteristics by a single tight-coil annealing or multi-layer annealing. The method can be widely used in the manufacture of magnetic steel sheets. The silicon steel sheet with excellent magnetic characteristics can be obtained by subjecting a cold-rolled silicon steel sheet containing, on a weight basis, not more than 1% of C, 0.2 to 6.5% of Si, and 0.05 to 5.0% of Mn to a tight-coil annealing or a multilayer annealing together with a substance which accelerates decarburization or with a combination of a substance which accelerates decarburization and a substance which accelerates demanganization, as separators in annealing.

Abstract: The annealing conditions of a cold rolled steel sheet are properly controlled so as to form a dense surface oxide layer, thereby improving the adherence strength of the insulating layer on non-oriented electrical steel sheet. The method includes the following steps. A steel slab is prepared which is composed of in weight %: 0.05% or less of C, 3.5% or less of Si, 1.5% or less of Mn, 0.15% or less of P, 0.015% or less of S, 1.0% or less of Al, one or more elements selected from a group consisting of 0.03-0.30% of Sn, 0.03-0.3% of Sb, 0.03-1.0% of Ni and 0.03-0.50% of Cu, the balance of Fe and unavoidable impurities. The steel slab is reheated, hot rolled, pickled after annealing or without annealing and cold-rolled. A low temperature annealing is carried out on the cold rolled steel sheet at a temperature of 750.degree.-850.degree. C. for 30 seconds to 5 minutes under a humid atmosphere having a dew point of 25.degree.-65.degree. C.

Abstract: A method for producing a grain oriented electromagnetic steel sheet exhibiting excellent magnetic flux density and excellent iron loss, including preparing a slab from steel capable of being formed into an oriented electromagnetic steel sheet, the steel comprising about 2.5 to 4.0 weight percent of Si and about 0.005 to 0.06 weight percent of Al; hot rolling the slab to a hot-rolled plate; cold rolling the hot-rolled plate up to two times, including an intermediate annealing between cold rollings, to form a cold-rolled steel sheet; decarburization and primary recrystallization annealing the steel sheet, the decarburization and primary recrystallization annealing including a first half and a second half, the decarburization and primary recrystallization annealing comprising rapidly heating the cold-rolled steel sheet at a rate of about 10.degree. C./min or more from about 450.degree. C. to a predetermined constant temperature between about 800.degree. to 880.degree. C.

Abstract: In order to provide a very low iron loss, it is necessary to render the surface of a steel sheet smooth (specular). In the present invention, this is effected in a finish annealing furnace to simultaneously attain a high magnetic flux density and a specular surface. Specifically, after the completion of decarburization annealing, a steel material is pickled to remove an oxide layer present on the surface of the steel sheet, coated with an annealing separator comprising a substance nonreactive or less reactive with SiO.sub.2 and then subjected to finish annealing to provide a grain oriented electrical steel sheet having a specular surface. Magnetic domain division and tension coating of the steel sheet can provide a low iron loss value. In the finish annealing, since no time is required for dehydration, the annealing time can be shortened.

Abstract: Low core loss oriented electrical steel sheet having a surface coating that has a Young's modulus that is not less than 100 GPa and a differential of thermal expansion coefficient relative to the sheet base metal that is not less than 2.times.10.sup.-6 /K and which contains not less than 10 percent, by weight, of crystallites with an average size of not less than 10 nm and an average crystal grain diameter that does not exceed 1000 nm, and a method of manufacturing same.

Abstract: Producing a grain oriented silicon steel sheet by controlling physical properties of the oxides layer, formed in decarburization annealing, in the surface layer of a steel sheet. A silicon compound is adhered to the surface of steel sheet before the decarburization annealing in an amount ranging from about 0.5 to 7.0 mg per square meter, expressed as Si, and the atmosphere of an earlier portion of the temperature holding process is adjusted to a ratio of steam partial pressure to the hydrogen partial pressure of less than about 0.7, and the atmosphere of the temperature rising process up to the temperature holding process is adjusted to an atmospheric composition lower than the atmospheric composition of the earlier portion of the temperature holding process, and the atmosphere of a later part of the temperature holding process is adjusted to an atmospheric composition lower than the atmospheric composition of the earlier part of the temperature holding process and in a range from about 0.005 to 0.2.

Abstract: The present invention provides a method of producing grain oriented electrical steel having excellent mechanical and magnetic properties. A hot processed strip having a thickness of 1.5-4.0 mm thickness a composition consisting essentially of 2.5-4.5% silicon, 0.1-1.2% chromium, less than 0.050% carbon, less than 0.005% aluminum, up to 0.1% sulfur, up to 0.14% selenium, 0.01-1% manganese and balance being essentially iron and residual elements, all percentages by weight. The strip has a volume resistivity of at least 45 .mu..OMEGA.-cm, at least 0.010% carbon so that an austenite volume fraction (.gamma..sub.1150.degree. C.) of at least 2.5% is present in the hot processed strip and each surface of the strip has an isomorphic layer having a thickness of at least 10% of the total thickness of the hot processed strip. The strip is cold reduced to an intermediate thickness, annealed, cold reduced to a final thickness and decarburized to less than 0.003% carbon.

Abstract: Disclosed is an annealing separator for production for grain-oriented electrical steel sheet, containing one or more compound selected from the following general formula;?Mg.sub.1-x M.sup.3+.sub.x !O ?Mg.sub.1-x M.sup.2+.sub.x !O or ?Mg.sub.1-x M.sup.2+.sub.x1 M.sup.3+.sub.x2 !OwhereM.sup.2+ is at least one bivalent element selected from the group consisting of Be, Ca, Ba, Sr, Sn, Mn, Fe, Co, Ni, Cu, Zn;M.sup.3+ is at least one tervalent element selected from the group consisting of Al, Fe, Cr, Co, B, Ti, Sb;0.01.ltoreq.x.ltoreq.0.40; x=x1+x2This annealing separator having a lower melting point and higher degree of reactivity is applied on the decarburization annealed strip, and improves the properties of the glass film, especially uniform film appearance and good sealing effect, and magnetic properties.

Abstract: A method of manufacturing a grain-oriented silicon steel sheet exhibiting excellent magnetic characteristics over the entire length of a coil thereof, which involves hot rolling a silicon steel slab containing aluminum and suitable for making a grain-oriented silicon steel sheet; annealing the steel sheet, as the need arises; cold rolling the steel sheet to a final thickness, the cold rolling including an intermediate annealing process; performing a heat effect treatment before, during or after the cold rolling; performing a decarburizing annealing; and performing a final annealing process. The method inhibits oxidation of the surfaces of the steel sheet during the cold rolling.

Abstract: Low core loss oriented electrical steel sheet having a surface coating that has a Young's modulus that is not less than 100 GPa and a differential of thermal expansion coefficient relative to the sheet base metal that is not less than 2.times.10.sup.-6 /K and which contains not less than 10 percent, by weight, of crystallites with an average size of not less than 10 nm and an average crystal grain diameter that does not exceed 1000 nm, and a method of manufacturing same.

Abstract: Method for producing a grain oriented silicon steel sheet comprises heating a silicon steel slab containing about:C : 0.01 to 0.10 wt %, Si: 2.5 to 4.5 wt %,Mn: 0.02 to 0.12 wt %, Al: 0.005 to 0.10 wt %,N : 0.004 to 0,015 wt %,to about 1280.degree. C. or higher and then subjecting it to hot rolling to prepare a hot-rolled steel sheet, subjecting the steel sheet to hot-rolled sheet annealing according to necessity, then subjecting it to one cold-rolling step or two or more cold-rolling steps with interposed intermediate annealing steps to prepare a cold-rolled steel sheet, and subjecting the cold-rolled steel sheet to decarburization annealing and finishing annealing, wherein the finishing rolling terminating temperature of the hot-rolling step is controlled to a range of about 900.degree. to 1100.degree. C., and the rolled sheet is processed so that the steel sheet temperature T(t) (.degree. C.

Abstract: A method for manufacturing an oriented electrical steel sheet includes the step of preparing a steel slab composed of in weight %: 0.035-0.050% of C, 2.9-3.3% of Si, less than 0.016% of P, 0.011-0.017% of soluble Al, 0.0080-0.012% of N, less than 0.007% of S, 0.06-0.18% of Ni+Cr, less than 0.32% of Mn with an Mn/S ratio of 20 or more, less than 0.6% of Cu with a Cu/Mn ratio of 1.5 or more, and balance of Fe and other inevitable impurities. The steel slab is heated at a temperature of 1250.degree.-1320.degree. C., and then hot rolled. The hot rolled slab is then cold rolled in two stages to a final sheet thickness, with a decarburization annealing being carried out at an intermediate thickness. The decarburized cold rolled sheet is coated with an annealing separator containing MgO as the main ingredient and then a finish annealing treatment is conducted, thereby obtaining a magnetically superior oriented electrical steel sheet.

Abstract: The present invention relates to the production of a grain oriented electrical steel composition having a volume resistivity of at least 50 micro-ohm-cm. The melt composition of the steel consists essentially of, in weight %, about 0.08% max carbon, about 0.015 to about 0.05% aluminum, 2.25 to 7% silicon, greater than about 0.5% manganese.sub.eq, about 0.001 to about 0.011% nitrogen, about 0.01% max sulfur, about 3% max chromium, about 1% max copper, about 2% max nickel and balance essentially iron. High levels of silicon are balanced with a manganese equivalent relationship which permits lower levels of carbon while still providing the desired levels of austenite during rolling and annealing. The processing also includes the addition of excess nitrogen to the steel prior to secondary grain growth which is subsequently removed during a purification treatment.

Abstract: A method for producing a grain-oriented silicon steel sheet in the coil shape having high magnetic induction and including AlN and MnSe as principal inhibitors is disclosed. In a series of processes for producing a grain-oriented silicon steel sheet, the oxide content on the steel sheet surface is controlled within a range of about 0.02 to 0.10 g/m.sup.2 before the temperature elevation phase of a decarburization annealing process, and the ratio of the steam partial pressure to the hydrogen partial pressure is controlled within a range of about 0.2 to 0.65 at a steel sheet surface temperature ranging from about 500.degree. to 750.degree. C. during the temperature elevation phase in a decarburization annealing process. The method promotes stable secondary recrystallized grain formation even in different coils or at different places in the same coil, such that fluctuation of magnetic properties is depressed.

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 grain oriented silicon steel sheet having excellent primary glass film property and magnetic property, comprising 2.0 to 5.0% by weight of Si, wherein a primary glass film formed during secondary recrystallization annealing is composed mainly of forsterite (Mg.sub.2 SiO.sub.4) and an oxide containing Al, mainly of spinel (MgAl.sub.2 O.sub.4), or Al and Si, mainly of cordierite (MgO.sub.2 Al.sub.4 Si.sub.5 O.sub.18) and/or sapphirine (Mg.sub.4 Al.sub.10 Si.sub.2 O.sub.23), and in an analysis of the surface of the steel sheet by glow discharge optical emission spectrometry analysis (GDS analysis), a peak derived from Al is separated from a peak derived from Mg, and, preferably, the peak derived from Al is separated from the peak derived from Mg and the distance (time) from the surface of the steel sheet at which the peak derived from Al is 1.2 times or more the distance from the surface of the steel sheet at which the peak derived from Mg appears.

Abstract: A method for making a lamination insulated by iron-manganese phosphate comprises the following operations:1. The lamination is treated with an acid or basic medium to eliminate the surface layer of the lamination that contains excess silicon and aluminum.2. The lamination is rinsed.3. The lamination is brought into contact with a solution of phosphoric acid containing iron phosphate and manganese phosphate for sufficient time to obtain an insulative layer of the required thickness.

Abstract: The present invention provides an annealing separator composition for coating grain oriented electrical steel prior to the final high temperature anneal for secondary grain growth. The magnesia based coating contains at least 20% silica on a water free basis. The large silica additions limit the interface between the coating and the base metal and results in a thick glass which is easily removed. The magnesia coating develops excellent magnetic properties and does not require the normal strong acid cleaning or special abrasive means to remove the glass film which forms. The bare electrical steel, which may be coated to enhance the punching properties, has improved the die life because the hard glass film has been substantially removed.

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: Disclosed is a method for producing a grain-oriented electrical steel sheet having mirror surface containing 0.8 to 4.8% of Si in the form of a strip which has been subjected to a conventional series of operations including hot rolling with or without annealing, cold rolling once or at least twice with intermediate annealing to obtain a final thickness, decarburization annealing with or without nitriding treatment, coating the steel sheet with an annealing separator mainly containing non-hydrating oxide and final annealing, the improvement comprising:satisfying the relationshipA!>0.2.times. O!where A! is the total concentration of alkali metal impurity in the annealing separator (weight %), andO! is the amount of oxygen contained in the steel sheet just prior to the final annealing (g/m.sup.2).

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: 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: 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 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: This invention is intended for providing a soft magnetic steel material having excellent DC magnetization properties and corrosion resistance, and capable of being manufactured at a low cost, and a method of manufacturing the same.The soft magnetic steel material of this invention contains 0.8 to 3.5% by weight of soluble aluminum, as well as limited amounts of C, total nitrogen, Si, Mn, P, S and total oxygen, and has an average ferrite crystal diameter of which the minimum has a specific relation to the thickness or diameter of the material. The material has a surface covered densely with aluminum oxide particles having a diameter of 0.01 to 5 microns. It exhibits a coercive force not exceeding 0.4 Oe in the absence of any strain and a magnetic flux density of 15,000 G or more at a magnetomotive force of 25 Oe. The aluminum oxide particles formed on the surface of the material are preferably formed with a density of 1.times.10.sup.12 to 1.times.10.sup.16 particles, or more preferably 1.times.10.sup.13 to 1.

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: 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 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: Method of manufacturing a grain oriented silicon steel sheet. An annealing separating agent mainly composed of MgO is coated on a surface of a decarburized silicon steel sheet. The silicon steel sheet is subjected to secondary recrystallization annealing and then purification annealing. The annealing separating agent contains Ti oxide or a Ti compound which can be oxidized by heating. The purification annealing is conducted in steps. A non-oxidizing atmosphere having a high nitrogen concentration is present in one step. A hydrogen atmosphere having a low nitrogen concentration is present in a subsequent step.

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: 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: 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: 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: 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: The present invention relates to a novel process for producing silicon and/or aluminum containing iron alloy product as well as the material produced from same in either sheet or bulk structure form for electromagnetic circuit application. The process entails modifying an iron feedstock containing less than about 2.5 wt % silicon, aluminum or a combination thereof. The process further consists of diffusion of silicon or silicon and aluminum or aluminum into an iron feedstock by a pack diffusion or a chemical vapor deposition method in which the iron feedstock is heated to a temperature at which diffusion occurs in the presence of a pack containing silicon and/or aluminum sources, a reducing agent, a catalyst, and a filler, or in the presence of a flowing gas stream containing a volatile silicon compound. The resulting iron alloy product, which has a silicon content in the range of 0.