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: 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: 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: 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: 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: 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: 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 steel slab containing not more than 0.005 wt % carbon, 1.0 to 4.0 wt % silicon, 0.1 to 1.0 wt % manganese, not more than 0.1 wt % phosphorus, not more than 0.005 wt % sulfur, and 0.1 to 2.0 wt % aluminum is directly sent to a hot rolling step without brief soaking, whereby Al and N are made soluble with respect to species other than AlN inevitably precipitated during hot rolling, and uniform and coarse AlN precipitation is formed by a subsequent annealing treatment in which the hot rolled plate is soaked at a temperature of 800.degree. to 1000.degree. C. for a period of time t defined as exp (-0.018T+19.4) .ltoreq.t.ltoreq.exp (-0.022T+25.4) wherein T is the soaking temperature (.degree.C.) and t is the soaking time (minutes). Uniform and satisfactory ferrite grain growth at the recrystallization annealing is provided thereby.

Abstract: A method of producing non-oriented electrical steel sheets having excellent magnetic properties which comprehends heating a steel at the low temperature for hot rolling, thereby to minimize re-solution of AlN particles when a slab is cooled, so that coarsening of AlN particles is facilitated during annealing the hot rolled sheet; and coiling at low temperatures for controlling the amount of scale generation. De-scaling is perfectly accomplished after the hot rolling, and the hot rolled sheet is annealed in a non-annealing atmosphere, thereby to control the oxidation and the nitriding to a minimum during annealing the hot rolled sheet, and the annealing conditions of the hot rolled sheet are specified for proper coarsening of the cohesion, taking into consideration the magnetic properties and the economics.

Abstract: This invention effectively smoothens the steel sheet surface after final cold rolling by removing oxidation scale produced on the steel sheet surface in the production steps of grain oriented silicon steel sheets, particularly after intermediate annealing and at a stage before the final cold rolling, or further forming grooves onto the steel sheet surface along the rolling direction, and hence can utilize high speed tandem rolling for the final cold rolling, whereby the production of grain oriented silicon steel sheets having excellent magnetic properties is realized in a high productivity.

Abstract: A method of manufacturing an oriented silicon steel sheet improved in magnetic characteristics, in which a hot-rolled steel sheet of oriented silicon steel containing about 0.01 to 0.10% by weight of Al and about 0.01 to 0.04% by weight of Sb as inhibitor components is heat-treated and cold-rolled one time or two or more times to have a final thickness. In the final heat treatment and final cold rolling alone, the steel sheet is quenched from a temperature of about 900.degree. to 1,100.degree. C. to a temperature equal to or lower than about 50.degree. C., is heat-treated at about 50.degree. to 150.degree. C. for about 30 sec. to 30 min. while applying a tensile stress of about 0.5 to 20 kg/mm.sup.2, is thereafter cold-rolled by a reduction rate of about 35 to 70% in a tandem rolling method, is aged at about 200.degree. to 400.degree. C. for about 10 sec. to 10 min., and is finished by cold rolling to have the final thickness.

Abstract: A method of producing grain oriented silicon steel sheets each having a low watt loss, at an inexpensive cost and a high operational efficiency, wherein surfaces of each silicon steel sheet are given a mirror surface is disclosed. After completion of a finish annealing, forsterite films on the surface of each grain oriented silicon steel sheet are removed therefrom, and thereafter, the silicon steel sheet is annealed within the temperature range of 1000.degree. C. or higher in an atmosphere composed of a mixture gas comprising 20 to 80% by volume of hydrogen gas and 0 to 80% by volume of an inert gas, whereby surfaces of the silicon steel sheet are given a mirror surface. Subsequently, tensile stress additive films are formed on the surfaces of the silicon steel sheet, and consequently, the resultant silicon steel sheet exhibits a remarkably reduced watt loss.

Abstract: The production of grain oriented silicon steel sheets comprises a combination of hot rolling step, cold rolling step, decarburization and primary recrystallization annealing step, annealing separator applying step and secondary recrystallization annealing and purification annealing step. In this case, the cold rolled sheet is subjected to an electrolytic degreasing in a silicate bath containing an iron concentration of 50-5000 mg/l, and Cu is adhered to the surface(s) of the sheet after the decarburization and primary recrystallization annealing in an amount of 400-2000 mg/m.sup.2 per one-side surface.

Abstract: A process of aluminizing magnetic steel sheets is disclosed. The process involves annealing a steel sheet in order to achieve partial secondary recrystallization, providing aluminum on the steel sheet, preferably by vacuum evaporation or immersion, and subjecting the steel sheet to a further heat treating step in order to diffuse the aluminum into the sheet and decrease impurities therein. Preferably, the partial secondary recrystallization anneal is performed in a neutral atmosphere such as nitrogen, while the final heat treating step is performed in a hydrogen atmosphere, and at a higher temperature than the above annealing step.

Abstract: A method for producing non-oriented electrical steel sheets comprising the steps of:making steel ingots comprising contents of:0.01 wt % and less C, 0.003 wt % and less N, 0.1 to 1.0 wt % Mn and 1.7 wt % and less Si;Si and Al satisfying the formulas of:(Al %).ltoreq.0.69 (Si %).sup.2 -2.29 (Si %)+1.90; and(Al %).gtoreq.0.10 (Si %).sup.2 -0.35 (Si %)+0.3, providing that (Si %) represents wt % Si content, and that (Al %) represents wt % Al content;other contents being Fe and impurities inevitable;hot-rolling slabs of the steel ingots at finishing temperature of 700.degree. to 900.degree. C. into hot-rolled steel strips to coil the hot-rolled steel strips; andcold-rolling the hot-rolled steel strips into cold-rolled steel strips, followed by annealing the cold-rolled strip sheets.

Abstract: Disclosed is a process for preparing a thin grain oriented electrical steel sheet having a final thickness of 0.05 to 0.25 mm from a silicon steel cast strip having a thickness of 0.2 to 5 mm and directly obtained from the molten steel by the synchronous continuous casting machine, in which the speed of movement of the strand relative to the inner wall surface of the casting mold is the same, and by which the traditional hot rolling process can be omitted, comprising 0.050 to 0.120% by weight of C, 2.8 to 4.0% by weight of Si and 0.05 to 0.25% by weight of Sn, wherein the starting silicon cast strip further comprises up to 0.035% by weight of S and 0.005 to 0.035% by weight of Se, with the proviso that the total amount of S and Se is in the range of 0.015 to 0.060% by weight, 0.050 to 0.090% by weight of Mn, with the proviso that the Mn content is in the range of {1.5.times.[content (% by weight) of S+content (% by weight) of Se]} to {4.5.times.

Abstract: A method of producing non-oriented magnetic steel plate having high magnetic flux density in a low magnetic field and uniform magnetic properties through the thickness direction, comprising selection of a heating temperature and finish rolling temperature to coarsen the size of the austenite grains and prevent refinement of the grain size in the rolling process, and annealing the steel after it has been rolled.

Abstract: The present invention relates to a process for preparing a unidirectional silicon steel sheet having a high magnetic flux density which comprises heating a silicon steel slab comprising by weight 0.025 to 0.075% of carbon, 2.5 to 4.5% of silicon, 0.015% or less of sulfur, 0.010 to 0.050% of acid-soluble aluminum, 0.0010 to 0.012% of nitrogen, 0.050 to 0.45% of manganese and 0.01 to 0.10% of tin and optionally 0.0005 to 0.0080% of boron with the balance being iron and unavoidable impurities, at 1200.degree. C.

Abstract: The present invention concerns a process for the production of semiprocessed non oriented grain electrical steel. More precisely it provides a solution to the technical problem of obtaining non oriented grain sheet or strip characterized by high magnetic permeability and low magnetic losses. According to the invention, starting from a steel with a low S, N and C content, through appropriate selection of hot-rolling variables and high-temperature annealing prior to cold rolling, a big improvement is achieved in the magnetic characteristics of the product, thanks to a better compromise between grain size and crystal orientation.

Abstract: An improvement in a method for improving the magnetic domain wall spacing of grain-oriented silicon steel sheet having an insulating coating thereof, wherein the sheet is subjected to metallic contaminants, particularly phosphorus and phosphorus compounds, to refine magnetic domains, followed by a rolling procedure, followed by a stress relief anneal to provide a smooth surface on the sheet and reduced core loss.

Abstract: A process for producing a grain-oriented electrical steel sheet having a superior magnetic characteristic, comprising the steps of: hot-rolling a silicon steel slab comprising 0.021 to 0.100 wt % C, 2.5 to 4.5 wt % Si, one or more elements for forming inhibitors, and the balance consisting of Fe and unavoidable impurities, to form a hot-rolled sheet; coiling the hot-rolled sheet at a coiling temperature lower than 700.degree. C.; subsequently cold-rolling the hot-rolled sheet at a reduction of 80% or more, effected by a plurality of rolling passes, to a final product sheet thickness; holding the steel sheet at a temperature of from 50.degree. to 500.degree. C. for 1 minute or longer at least once at the stage between the rolling passes of the cold rolling; decarburization-annealing the cold-rolled sheet; and final-annealing the decarburization-annealed sheet.

Abstract: A method of producing non-oriented magnetic steel plate that comprises hot-rolling high-purity steel and adjusting the grain size together with the dehydrogenation treatment to produce a uniform ferrite grain diameter and impart uniform magnetic properties in a low magnetic field through the thickness direction.

Abstract: The present invention provides a wound core having a low core loss and not susceptible to a disappearance of the core loss lowering effect due to a magnetic domain refining even when stress-relief annealing is conducted after fabrication of a steel strip into a wound core, through a process which comprises, fabricating a very thin silicon steel strip comprising by 6.5% weight or less of silicon with the balance consisting essentially of iron and having a sheet thickness of 100 .mu.m or less and a magnetic flux density (B.sub.8 value) of 1.80T or more into a wound core, subjecting the wound core to stress-relief annealing, unwinding the very thin silicon steel strip from the core, introducing into the very thin silicon steel strip a linear or dotted local strain in a direction at an angle of 45.degree. to 90.degree. to the rolling direction of the thin strip, and rewinding the thin strip onto the core.

Abstract: The present invention is to produce non-oriented silicon steel sheets having excellent magnetic properties in dependence upon a hot direct rolling, wherein the slab is directly sent to the direct rolling without maintaining the heat and soaking, whereby others than AlN precipitated during hot rolling check the precipitation of AlN, and a delay time is taken between the roughing and the finish rolling so that precipitating nuclei of AlN are introduced into the steel, and uniform and coarse AlN precipitation is formed by a subsequent annealing treatment, thereby to enable to provide uniform and satisfied ferrite grain growth at the recrystallization annealing.

Abstract: A method of producing non-oriented magnetic steel heavy plate that has good magnetic properties in a low magnetic field that comprises hot-rolling high-purity steel, adjusting the crystal grain size and dehydrogenation treatment, whereby the a uniform ferrite grain diameter is imparted to the steel.

Abstract: A method and apparatus are provided for domain refinement of texture annealed and insulation coated grain-oriented silicon steel strip by contacting the insulated steel surface to be scribed with a discharge electrode, providing a high voltage-low current and low voltage-high current to the electrode, moving the electrode across the steel while essentially maintaining contact therewith, and marking the steel with a plurality of indentations generally aligned across the steel surface by pulsing the high current to produce a plurality of electrical discharges.

Abstract: A method is provided for domain refinement of electrical sheet products, such as grain-oriented silicon steel and amorphous magnetic materials, by subjecting at least one surface of the steel to an electron beam treatment to produce narrow substantially parallel bands of treated regions separated by untreated regions substantially transverse to the direction of strip manufacture to improve core loss without damaging the surface or any coating thereon.

Abstract: The iron loss is reduced by irradiating plasma flame to the surface of the grain oriented silicon steel sheet, wherein the irradiation interval (l) of plasma flame is controlled so as to satisfy the following equation (1):22-2.5D.ltoreq.l.ltoreq.36-2.5D (1)(D is an average secondary recrystallized grain size of the steel sheet).

Abstract: A method is provided for heat resistant domain refinement of texture annealed and insulation coated grain-oriented silicon steel strip and amorphous magnetic materials by subjecting at least one surface of the steel to an electron beam treatment to produce permanent defects to effect domain refinement with narrow substantially parallel bands of treated regions separated by untreated regions substantially transverse to the direction of strip manufacture.

Abstract: Ultra-rapid annealing of nonoriented electrical steel is conducted at a rate above 100.degree. C. per second on prior to or as part of the strip decarburization and/or annealing process to provide an improved texture and, thereby, improved permeability and reduced core loss. During the ultra-rapid heating of cold-rolled strip, the recrystallization texture is enhanced by more preferential nucleation of {100}<uvw> and {110}<uvw> oriented crystals and reduced formation of {111}<uvw> oriented crystals. The preferred practice has a heating rate above 262.degree. C. per second to a peak temperature between 750.degree. C. and 1150.degree. C. and held at temperature for 0 to 5 minutes.

Abstract: Oriented silicon steel is heated in a slab furnace at temperatures above 1260.degree. C. prior to hot rolling. The slab surfaces in the furnace are exposed to molten slag, variable atmosphere conditions and refractory interaction from the hearth. The slab surface prior to hot rolling has a major importance for cold rolling and the quality of the glass film.A rapid oxidation treatement of the slab just prior to the scale breaker or first rolling stand corrects a silicon-free iron layer condition which causes streaks in the glass film. The oxidation treatment blows gas having at least 30% oxygen for a sufficient time and velocity to provide a surface which will develop a continuous fayalite layer in subsequent processing and provide for the formation of a continuous glass film.

Abstract: Ultra-rapid annealing of grain oriented electrical steel to a temperature prior to the final high temperature anneal results in improved texture and smaller secondary grain size. The ultra-rapid anneal requires heating the strip to a temperature above about 675.degree. C. (1250.degree. F.) at a rate above 100.degree. C. per second (180.degree. F. per second). The ultra-rapid anneal is performed after the first stage of cold rolling and prior to or as part of the decarburization anneal. The material will survive a subsequent stress relief anneal and may be further improved by various domain treatments. The ultra-rapid anneal increases productivity and procedures improved core loss properties.

Abstract: A method for producing grain-oriented electrical steel sheet having metallic luster and excellent punching property comprises the steps of decarbonization annealing a grain-oriented electrical steel sheet which has been cold rolled to a final thickness, coating the decarbonization-annealed sheet with an annealing separator consisting of magnesium blended with one or more salts of alkali metal or alkaline-earth metal, and finish annealing the coated sheet.

Abstract: In the production of a grain-oriented electrical steel sheet, a slab (1) is current-conduction heated, using the slab (1) as a resistor, under a condition of being on or below an apparent current density (I) of from 40 (A/cm.sup.2) to 0.5 P.sup.2 +100 (A/cm.sup.2), P being a pressure of electrodes in kg/cm.sup.2.

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: In the production of a grain-oriented electrical steel sheet by utilizing an AIN main inhibitor and at least twice cold-rolling with a heavy final reduction, improved magnetic properties are stably obtained by controlling the cooling speed (R) in the cooling process of a hot-rolled sheet annealing (R.gtoreq.5.degree.C./sec from 600.degree.-200.degree. C.) and by inter-pass aging (50.degree.-500.degree. C. for 1 minute or more) during the first cold-rolling.

Abstract: The present invention relates to an improvement in the precipitation annealing of a hot-rolled steel sheet or strip which is carried out immediately before cold-rolling in the production of a grain-oriented electromagnetic steel sheet or strip. Conventionally, precipitation annealing is carried out by heating a steel strip to a temperature of from 750.degree. to 1200.degree. C. and then quenching it. The present invention proposes to control the cooling rate during primary cooling, i.e. from a holding temperature (T.sub.1 temperature) of from 1080.degree. to 1200.degree. C. down to an intermediate temperature (T.sub.2 temperature) of from 900.degree. to 980.degree. C., and to control the staying time during primary cooling so that excellent magnetic properties can be obtained regardless of the unavoidable variation in the Al and Si content. The present invention also proposes to control the rate of temperature elevation between 800.degree. C.

Abstract: Method for the production of a single oriented silicon steel sheet having excellent magnetic property which comprises providing a silicon steel slab containing 0.010.about.0.10% C, 2.5.about.4.5% Si, 0.02.about.0.15% Mn, and a total of 0.008.about.0.080% of one or two of S and Se, hot rolling the silicon steel slabing to sheet, and subjecting the hot rolled sheet to a two-step annealing procedure wherein the first half is at a temperature of 1000.degree..about.1200.degree. C. and the latter half at 750.degree..about.980.degree. C., and to at least two cold rolling steps.

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: Grooves are formed on a finish-annealed electrical steel sheet by applying a mean load of from 90 to 220 kg/mm.sup.2 to the steel sheet, which is then heat treated at a temperature of 750.degree. C. or higher, and thereby fine crystal grains are generated at the strain-introduced sites of the steel sheet. The fine crystal grain reduces the watt-loss value. Such a watt-loss improving effect is not impaired even by stress-relief annealing.

Abstract: A process for the production of an electrical steel sheet having the ideal (100) [001] cube texture of iron of iron alloy, comprising cold rolling a sheet of a single crystal or large grained crystals of iron or iron alloy, in which said single crystal is or a majority of said large grained crystals are oriented so that the pole of the {114} plane may form an angle not greater than 15.degree. with the normal direction of the plane of the sheet, and the <401> direction may form an angle of not greater than 15.degree. with a single direction in the plane of the sheet, in said single direction at a rolling reduction of at least 40%, and annealing the rolled sheet to form a primary recrystallization texture of fine grains of an average grain size of not larger than 5 mm under conditions preventing the occurrence of secondary recrystallization.

Abstract: A method and apparatus are provided for scribing grain-oriented silicon steel to improve core losses and which can be used at typical strip line speeds. The method and apparatus provide for moving the strip and forming the strip about an axis parallel to the strip movement, rotating a body having scribing means mounted at or about the periphery and scribing the strip at selected spaced-apart intervals substantially transverse to the strip direction.

Abstract: A method of producing cube-on-edge oriented silicon steel strip and sheet from strand cast slabs, wherein a slab is prerolled at a temperature not exceeding 1673.degree. K. with a reduction in thickness up to 50%, and the prerolled slab is reheated to a temperature between 1533.degree. and 1673.degree. K. prior to hot rolling. The slab prerolling temperature, percentage of reduction in prerolling, and the reheat temperature are correlated in accordance with a specific equation in order to control the strain rate during prerolling and to obtain an average grain diameter not exceeding about 9 mm after reheating.

Abstract: This invention realizes the improvement of the surface properties and the magnetic characteristics in such a way that a large amount of Si of 3.1-4.5% is incorporated into a raw material, a small amount of Al and a very small amount of S or Se are used as inhibitor together with Mo, and the slab heating is so performed at a temperature of not lower than 1,270.degree. C. that the scale loss may reach 2.7-5.0%, whereby the inhibitor is fully dissociated and solid-solved to conspicuously strengthen the growth inhibiting effect against the primary recrystallization grains in the secondary recrystallization annealing for promoting the growth of the secondary recrystallization grains in the {110}<001> orientation, thereby forming the secondary recrystallization texture extremely strongly arranged in the {110}<001> orientation, so that a high magnetic flux density and a low iron loss is attained with effectively preventing cracks in hot rolling after slab soaking.

Abstract: A method is provided for final texture annealing silicon steel to produce a cube-on-edge grain orientation having lower core losses and higher magnetic permeability. The method includes using a controlled heating cycle including a substantially isothermal hold at a selected recrystallization temperature of about 1650.degree. F. to improve secondary recrystallization and the Goss texture (110) [001].

Abstract: A method is provided for improving the core losses of silicon-iron steels, especially grain-oriented silicon steels, by improving the uniformity and quality of the base insulating coating; the method includes winding coated steel strip at winding tensions sufficient to form a coil having good coil integrity and sufficiently loose to improve base coating formation.

Abstract: The invention provides a method of treating grain oriented steel sheet or strip to refine domain spacing by subjecting the steel sheet or strip to electrical discharge to create a line of surface ablation and stress thereacross, together with apparatus for carrying out the method.

Abstract: It has been found that ferromagnetic sheet material can be scribed in order to reduce watt losses by a thermal method involving rapid heating of small areas or narrow bands of the material in a manner that produces sudden thermal expansion to a degree sufficient to produce plastic deformation within the thermally treated zone. This method has been found to be particularly applicable to electrically insulative coated ferromagnetic sheet wherein it has been found that a laser operating in a continuous wave or extended pulse mode can produce the desired deformation in the ferromagnetic material without damage to the coating properties.