| Class / Patent application number | Description | Number of patent applications / Date published |
|---|
| 148208000 | With decarburizing or denitriding | 19 |
| 20090126832 | Method of production of grain-oriented electrical steel sheet having a high magnetic flux density - In a production of grain-oriented electrical steel sheet that is heated at a temperature of not higher than 1350° C., (a) the hot-rolled sheet is heated to a prescribed temperature of 1000° C. to 1150° C., and after recrystallization is annealed for a required time at a lower temperature of 850° C. to 1100° C., or (b) in the hot-rolled sheet annealing process decarburization is conducted to adjust the difference in the amount of carbon before and after decarburization to 0.002 to 0.02 mass %. In the temperature elevation process used in the decarburization annealing of the steel sheet, heating is conducted in the temperature range of 550° C. to 720° C. at a heating rate of at least 40° C./s, preferably 75 to 125° C./s, utilizing induction heating for the rapid heating used in the temperature elevation process in decarburization annealing. | 05-21-2009 |
| 20090165895 | Method of production of grain-oriented electrical steel sheet with high magnetic flux density - The present invention provides a method of production of grain-oriented electrical steel sheet comprising making a slab heating temperature 1280° C. or less, annealing hot rolled sheet by (a) a process of heating it to a predetermined temperature of 1000 to 1150° C. to cause recrystallization, then annealing by a temperature lower than that of 850 to 1100° C. or by (b) decarburizing in annealing the hot rolled sheet so that a difference in amounts of carbon of the steel sheet before and after annealing the hot rolled sheet becomes 0.002 to 0.02 mass % and performing the heating in the temperature elevation process of the decarburization annealing under conditions of a heating rate of 40° C. or more, preferably 75 to 125° C./s while the temperature of the steel sheet is in a range from 550° C. to 720° C. and utilizing induction heating for rapid heating in the temperature elevation process of decarburization annealing. | 07-02-2009 |
| 20100300583 | PROCESS FOR THE PRODUCTION OF A GRAIN ORIENTED MAGNETIC STRIP - A process for the production of a grain oriented magnetic strip, made of steel containing 2.3 to 5.0% of silicon, obtained by producing a hot-rolled sheet containing a distribution of second phases capable of controlling the secondary recrystallization by means of a two-step hot-rolling with an intermediate annealing, and by changing it into the final product. | 12-02-2010 |
| 20100319812 | METHOD FOR PRODUCING A SURFACE-DECARBURISED HOT-ROLLED STRIP - Disclosed is a method which allows steel strip to be produced in which high hardness and good formability are combined. The following steps of operation are followed.
| 12-23-2010 |
| 20110155285 | MANUFACTURING METHOD OF GRAIN-ORIENTED ELECTRICAL STEEL SHEET - A slab with a predetermined composition is heated at 1280° C. to 1390° C. to make a substance functioning as an inhibitor to be solid-solved (step S | 06-30-2011 |
| 20110162758 | FURNACE OF HEAT TREATMENT, THE METHOD OF HEAT TREATMENT, AND THE DIRECTIONS FOR USE OF FURNACE OF HEAT TREATMENT - A furnace of heat treatment capable of keeping a stable nitriding quality for a long period of time is provided. The furnace of heat treatment performs a halogenation treatment and a nitriding treatment by heating a steel material under a predetermined atmosphere. An alloy containing Ni ranging between 50 mass % or more and 80 mass % or less and Fe ranging between 0 mass % or more and 20 mass % or less is used as a material of surfaces of core internals exposed to a treatment space where the nitriding treatment is performed. Accordingly, a nitriding reaction is hardly caused on the surfaces of the core internals, and the halogenation treatment and the nitriding treatment to an article to be treated can be stably executed for a long period of time. Further, a nitrided layer can be stably formed according to purposes on any types of steel materials including a steel type hard to be nitride. | 07-07-2011 |
| 20120018049 | PROCESS FOR THE PRODUCTION OF GRAIN-ORIENTED MAGNETIC SHEET STARTING FROM THIN SLAB - Process for the production of grain-oriented magnetic sheets, wherein a slab made of steel having a thickness of ≦100 mm, containing Si in the range comprised between 2.5 and 3.5% by weight, is subjected to a thermo-mechanical cycle comprising the following operations:—optional first heating to a temperature T1 no higher than 1250° C.·first rough hot-rolling, in a first rough hot rolling mill, to a temperature T2 comprised between 900 and 1200° C., the reduction ratio (% Rid) applied to the first rough hot-rolling being adjusted so as to be:—of at least 80%, in the absence of a subsequent heating to a temperature T3—determined by the following relationship % Rid=80 (T3−T2)/5, in the presence of a subsequent heating to a temperature T3—optional second heating to a temperature T3 >T2·second finishing hot-rolling, in a second fmishing hot rolling mill, to a temperature T4| 01-26-2012 | |
| 20120037277 | METHOD OF TREATING STEEL FOR GRAIN-ORIENTED ELECTRICAL STEEL SHEET AND METHOD OF MANUFACTURING GRAIN-ORIENTED ELECTRICAL STEEL SHEET - A surface temperature of a slab is decreased down to 600° C. or lower between start of continuous casting (step S | 02-16-2012 |
| 20120103474 | MANUFACTURING METHOD OF GRAIN-ORIENTED ELECTRICAL STEEL SHEET - A silicon steel material is heated in a predetermined temperature range according to contents of B, N, Mn, S, and Se (step S | 05-03-2012 |
| 20120111455 | MANUFACTURING METHOD OF GRAIN-ORIENTED MAGNETIC STEEL SHEET - A nitriding treatment (Step S | 05-10-2012 |
| 20120222777 | PROCESS TO MANUFACTURE GRAIN-ORIENTED ELECTRICAL STEEL STRIP AND GRAIN-ORIENTED ELECTRICAL STEEL PRODUCED THEREBY - A process to manufacture grain-oriented electrical steel (GOES) strip and a product produced by the process are provided. A molten silicon-alloyed steel is continuously cast in a strand having a thickness in the range of from 50 to 100 mm and subjected to hot- rolling in a plurality of uni-directional rolling stands to produce final hot-rolled strip coils having a thickness in the range of from 0.7 to 4.0 mm followed by a continuous annealing the hot-rolled strip, cold rolling, continuous annealing the cold-rolled strip to induce primary recrystallisation and, optionally, decarburization and/or nitriding, coating the annealed strip, annealing the coiled strip to induce secondary recrystallisation, continuous thermal flattening annealing of the annealed strip and coating the annealed strip for electric insulation. | 09-06-2012 |
| 20120247618 | HIGH STRENGTH STEEL MATERIAL AND HIGH STRENGTH BOLT EXCELLENT IN DELAYED FRACTURE RESISTANCE AND METHODS OF PRODUCTION OF SAME - A high strength steel material which is excellent in delayed fracture resistance containing, by mass %, C: 0.10 to 0.55%, Si: 0.01 to 3%, and Mn: 0.1 to 2%, further containing one or both of V: 1.5% or less and Mo: 3.0% or less, the contents of V and Mo satisfying V+1/2Mo>0.4%, further containing one or more of Cr: 0.05 to 1.5%, Nb: 0.001 to 0.05%, Cu: 0.01 to 4%, Ni: 0.01 to 4%, and B: 0.0001 to 0.005%, and having a balance of Fe and unavoidable impurities, the structure being a mainly tempered martensite structure, the surface of the steel material being formed with (a) a nitrided layer having a thickness from the surface of the steel material of 200 μm or more and a nitrogen concentration of 12.0 mass % or less and higher than the nitrogen concentration of the steel material by 0.02 mass % or more and (b) a low carbon region having a depth from the surface of the steel material of 100 μm or more to 1000 μm or less and having a carbon concentration of 0.05 mass % or more and 0.9 time or less the carbon concentration of the steel material. | 10-04-2012 |
| 20120312423 | METHOD OF MANUFACTURING GRAIN-ORIENTED ELECTRICAL STEEL SHEET - Hot rolling is performed on a steel with a predetermined composition containing Ti: 0.0020 mass % to 0.010 mass % and/or Cu: 0.010 mass % to 0.50 mass % to obtain a hot-rolled steel sheet. Annealing is performed on the hot-rolled steel sheet to obtain an annealed steel sheet. Cold rolling is performed on the annealed steel sheet to obtain a cold-rolled steel sheet. Decarburization annealing is performed on the cold-rolled steel sheet at a temperature of 800° C. to 950° C. to obtain a decarburization annealed steel sheet. Then, nitridation treatment is performed on the decarburization annealed steel sheet at 700° C. to 850° C. to obtain a nitrided steel sheet. Finish annealing is performed on the nitrided steel sheet. | 12-13-2012 |
| 20120312424 | METHOD OF MANUFACTURING GRAIN-ORIENTED ELECTRICAL STEEL SHEET - Hot rolling is performed on a steel with a predetermined composition containing Ti: 0.0020 mass % to 0.010 mass % and/or Cu: 0.010 mass % to 0.50 mass % to obtain a hot-rolled steel sheet. Annealing is performed on the hot-rolled steel sheet to obtain an annealed steel sheet. Cold rolling is performed on the annealed steel sheet to obtain a cold-rolled steel sheet. Decarburization annealing and nitridation annealing are performed on the cold-rolled steel sheet to obtain a decarburized nitrided steel sheet. Then, finish annealing is performed on the decarburized nitrided steel sheet. When obtaining the decarburized nitrided steel sheet, heating on the cold-rolled steel sheet is started in a decarburizing and nitriding atmosphere, then first annealing is performed at a first temperature within a predetermined range, and then second annealing is performed at a second temperature within a predetermined range. | 12-13-2012 |
| 20130000786 | MANUFACTURING METHOD OF GRAIN-ORIENTED ELECTRICAL STEEL SHEET - A predetermined steel containing Te: 0.0005 mass % to 0.0050 mass % is heated to 1320° C. or lower to be subjected to hot rolling, and is subjected to annealing, cold rolling, decarburization annealing, and nitridation annealing, and thereby a decarburized nitrided steel sheet is obtained. Further, an annealing separating agent is applied on the surface of the decarburized nitrided steel sheet and finish annealing is performed, and thereby a glass coating film is formed. The N content of the decarburized nitrided steel sheet is set to 0.0150 mass % to 0.0250 mass % and the relationship of 2×[Te]+[N]≦0.0300 mass % is set to be established. Note that [Te] represents the Te content and [N] represents the N content. | 01-03-2013 |
| 20130061985 | METHOD OF MANUFACTURING GRAIN-ORIENTED ELECTRICAL STEEL SHEET - In a method of manufacturing a grain-oriented electrical steel sheet including a nitriding treatment (step S | 03-14-2013 |
| 20130292006 | GRAIN-ORIENTED ELECTRICAL STEEL SHEET AND MANUFACTURING METHOD THEREOF - A grain-oriented electrical steel sheet being a grain-oriented electrical steel sheet containing Si of 0.8 mass % to 7 mass %, Mn of 0.05 mass % to 1 mass %, B of 0.0005 mass % to 0.0080 mass %, each content of Al, C, N, S, and Se of 0.005 mass % or less, and a balance being composed of Fe and inevitable impurities and having a glass coating film made of composite oxide mainly composed of forsterite on the steel sheet surface, in which when glow discharge optical emission spectrometry (GDS) to the surface of a secondary coating film formed on the surface of the glass coating film under a predetermined condition is performed, a peak, of B, in emission intensity having a peak position in emission intensity different from a peak position, of Mg, in emission intensity is obtained and the peak position, of B, in emission intensity from the steel sheet surface is deeper than the peak position, of Mg, in emission intensity. | 11-07-2013 |
| 20140069555 | Fe-BASED METAL SHEET AND MANUFACTURING METHOD THEREOF - A cast slab containing C: less than 0.02 mass % and made of an Fe-based metal of an α-γ transforming component is subjected to hot rolling at a temperature of an A3 point or higher and is subjected to α-region rolling at a temperature of 300° C. or higher and lower than the A3 point, and thereby a base metal sheet having a {100} texture in a surface layer portion is fabricated. Then, by performing a heat treatment under predetermined conditions, an Fe-based metal sheet is obtained in which a Z value is not less than 2.0 nor more than 200 when intensity ratios of respective {001}<470>, {116}<6 12 1>, and {223}<692> directions in a sheet plane by X-ray diffraction are set to A, B, and C respectively and Z=(A+0.97B)/0.98C is satisfied. | 03-13-2014 |
| 20140261895 | Method for Producing a Grain-Oriented Electrical Steel Flat Product Intended for Electrotechnical Applications - The invention relates to a method for producing a grain-oriented steel flat product for electrotechnical applications, wherein, in a production step, “decarburising and nitriding annealing” is carried out in two stages. The first stage of the annealing process extends over a first time interval, which comprises heating the cold strip starting from a start temperature to a first target annealing temperature and holding it at this target annealing temperature, and the second stage of the annealing process extends over a second time interval, in which the cold strip is heated to a second target annealing temperature and subsequently held at this target annealing temperature. | 09-18-2014 |
