EP0947597B2 - Verfahren zur Herstellung eines kornorientierten Elektrobleches mit ausgezeichneten magnetischen Eigenschaften - Google Patents

Verfahren zur Herstellung eines kornorientierten Elektrobleches mit ausgezeichneten magnetischen Eigenschaften Download PDF

Info

Publication number
EP0947597B2
EP0947597B2 EP99105071.7A EP99105071A EP0947597B2 EP 0947597 B2 EP0947597 B2 EP 0947597B2 EP 99105071 A EP99105071 A EP 99105071A EP 0947597 B2 EP0947597 B2 EP 0947597B2
Authority
EP
European Patent Office
Prior art keywords
annealing
steel sheet
hot
grain
temperature
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP99105071.7A
Other languages
English (en)
French (fr)
Other versions
EP0947597A3 (de
EP0947597B1 (de
EP0947597A2 (de
Inventor
Tomoji c/oNIPPON STEEL CORP. YAWATA WORKS Kumano
Norikazu c/oNIPPON STEEL CORP YAWATA WORK Fujii
Katsuro c/o NITTETSU PLANT DESIGNING CORP Kuroki
Koji c/oNIPPON STEEL CORP. YAWATA WORKS Yamasaki
Yoshifumi NIPPON STEEL CORP. YAWATA WORKS Ohata
Hisashi c/o NIPPON STEEL CORP. YAWATA WORKS Mogi
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nippon Steel Corp
Original Assignee
Nippon Steel and Sumitomo Metal Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Family has litigation
First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=26425094&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=EP0947597(B2) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by Nippon Steel and Sumitomo Metal Corp filed Critical Nippon Steel and Sumitomo Metal Corp
Priority to DE69923102.7T priority Critical patent/DE69923102T3/de
Publication of EP0947597A2 publication Critical patent/EP0947597A2/de
Publication of EP0947597A3 publication Critical patent/EP0947597A3/de
Application granted granted Critical
Publication of EP0947597B1 publication Critical patent/EP0947597B1/de
Publication of EP0947597B2 publication Critical patent/EP0947597B2/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties of ferrous metals or ferrous alloys by deformation combined with, or followed by, heat treatment
    • C21D8/12—Modifying the physical properties of ferrous metals or ferrous alloys by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties
    • C21D8/1244—Modifying the physical properties of ferrous metals or ferrous alloys by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties characterised by the heat treatment
    • C21D8/1255—Modifying the physical properties of ferrous metals or ferrous alloys by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties characterised by the heat treatment with diffusion of elements, e.g. decarburising, nitriding
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties of ferrous metals or ferrous alloys by deformation combined with, or followed by, heat treatment
    • C21D8/12—Modifying the physical properties of ferrous metals or ferrous alloys by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D3/00—Diffusion processes for extraction of non-metals; Furnaces therefor
    • C21D3/02—Extraction of non-metals
    • C21D3/04—Decarburising
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties of ferrous metals or ferrous alloys by deformation combined with, or followed by, heat treatment
    • C21D8/12—Modifying the physical properties of ferrous metals or ferrous alloys by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties
    • C21D8/1216—Modifying the physical properties of ferrous metals or ferrous alloys by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties characterised by the working steps
    • C21D8/1227—Warm rolling
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties of ferrous metals or ferrous alloys by deformation combined with, or followed by, heat treatment
    • C21D8/12—Modifying the physical properties of ferrous metals or ferrous alloys by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties
    • C21D8/1216—Modifying the physical properties of ferrous metals or ferrous alloys by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties characterised by the working steps
    • C21D8/1233—Cold rolling
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties of ferrous metals or ferrous alloys by deformation combined with, or followed by, heat treatment
    • C21D8/12—Modifying the physical properties of ferrous metals or ferrous alloys by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties
    • C21D8/1244—Modifying the physical properties of ferrous metals or ferrous alloys by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties characterised by the heat treatment
    • C21D8/1272—Final recrystallisation annealing

Definitions

  • This invention relates to a method of producing a grain-oriented electrical steel sheet excellent in magnetic characteristics for use primarily in the cores of electrical transformers and the like.
  • a generally known method used to produce a grain-oriented electrical steel sheet is to heat the slab to a very high temperature between 1350°C and a maximum of 1450°C and to hold (soak) the slab at this temperature for a period sufficient to ensure uniform heating throughout its entirety. This is for putting MnS, AlN and the like into solid solution so that they function as inhibitors. Since this method requires the slab to be heated to a very high temperature, however, it involves various problems in actual production. For example, (1) the slag produced by melting of the slab surface layer causes difficult problems from the point of heating furnace maintenance, (2) the desired hot-rolling temperature is difficult to secure, and (3) yield is reduced by large edge cracks occurring in hot-rolled strip.
  • the nitriding conditions become inconstant because of the variation in the composition of the oxide layer formed during decarburization and the resulting variation in the amount of nitrides formed may cause unstable secondary recrystallization.
  • the method according to JP-A-9-118964 which uses a large amount of Mn in order to improve the iron loss of the steel sheet by increasing its resistivity, is not suitable for industrial production because it is very liable to produce defects in the glass film.
  • These methods are characterized by not requiring an additional process such as the nitriding in the first category of methods.
  • Cu x S as an inhibitor for controlling secondary recrystallization and the method is not suitable for producing a high permeability grain-oriented electrical steel sheet having weak texture by applying a final cold rolling reduction ratio of greater than 80% ( Iron and Steel, p. 2049, No. 15, Vol. 70, No. 1984 ). Specifically, as shown in Fig.
  • Fig. 4 shows the relationship between the magnetic flux density (B 8 :T) and the iron loss (W 17/50 :W/kg) of a thickness of 0.30 mm product.
  • ⁇ represents the TGO of JP-A-6-322443 and the broken line indicates the results of inventor tests and shows the secondary recrystallization to be poor. ⁇ indicates Comparative Examples of the present invention.
  • JP-A-6-322443 calls for precipitation of at least 60% of the total N content in the hot-rolled strip state as AlN
  • the hot-rolled strip having the composition shown in the Examples (Mn, S, Al, N) and obtained at a slab heating temperature on the level of 1270°C uniform precipitation of AlN and MnS, which are precipitates whose solubility product is a quadratic function, is extremely difficult industrially. It is therefore impossible to obtain uniform magnetic characteristics throughout the coil length.
  • WO 98/41659 relates to a process for the inhibition control in the production of grain-oriented electrical sheets in which the hot-rolled strip inhibition is controlled through careful balancing of the copper, aluminium and carbonium contents to obtain optimum grain dimensions during the decarburization annealing and to allow a subsequent high-temperature continuous thermal treatment.
  • WO 98/08987 relates to a process for the production of grain oriented electrical steel strip having high magnetic characteristics, starting from thin slab in which the control of condition of thin real continuous casting allows to obtain advantageous solidification structure and precipitates and to decriticize the process for controlling the grain dimensions.
  • An object of this invention is to enable stable and simple production of a grain-oriented electrical steel sheet excellent in magnetic characteristics by compensating for the drawbacks of the technologies in both of the foregoing categories.
  • the most salient feature of this invention is that, in a method for producing a grain-oriented electrical steel sheet permitting a lower slab heating temperature than heretofore owing to avoidance of MnS as the main inhibitor for secondary recrystallization, it causes MnS (or MnSe), Cu x S (or CuSe) etc.
  • an object of the present invention is to metallurgically separate the functioning stages of inhibitors playing major roles in production of the grain-oriented electrical steel sheet and to cause each to fulfill its own function using different substances.
  • the temperature of the decarburization annealing during which primary recrystallization takes place is generally low, i.e., no higher than 930°C. At this stage, therefore, the strong inhibitor formed during high-temperature hot rolling in the conventional method is unnecessary. Since the present invention uses sulfides and/or selenides as the primary inhibitors, the temperature dependence of the primary recrystallization grains is very small and, therefore, the temperature of the primary recrystallization annealing (actually the decarburization annealing) need not be greatly modified. This ensures very high stability of the primary oxide layer composition and the amount of nitrides formed by the ensuing nitriding, remarkably reduces glass film defects, and also eliminates nonuniformity of secondary recrystallization to enable stable industrial production.
  • the secondary recrystallization requires an inhibitor made stable against high temperatures by addition of sulfides and/or selenides.
  • AlN formed by the nitriding mainly provides this stabilizing effect.
  • Al combines with N to form AlN, which functions mainly as a secondary inhibitor. Some AlN is formed before nitriding and some is formed during the high-temperature annealing after nitriding. An Al content of 0.0010 ⁇ 0.035% is needed to ensure the required amounts of AlN both before and after nitriding. When the Al content is outside this range, the primary recrystallization grain diameter becomes difficult to control and the secondary recrystallization therefore does not proceed stably.
  • the present invention uses mainly sulfides and selenides to control the primary recrystallization grains.
  • AlN contained in the slab is also necessary for primary recrystallization grain control, and control of the primary recrystallization grain diameter is difficult when the N content is below 0.0030%.
  • the upper limit of the N content is defined as 0.010% because at higher contents defects, i.e., blisters, occur on the steel sheet surface. Owing to this limitation, the amount of N contained in the slab is not sufficient to control the secondary recrystallization. This is why the nitriding explained later is necessary.
  • Cr has a beneficial effect on formation of a forsterite film (glass film).
  • the beneficial effects on formation of a forsterite film are slight.
  • Ni is highly effective for obtaining uniform dispersion of precipitates as primary and secondary inhibitors, its addition further improves and stabilizes the magnetic characteristics. It has no effect when added to less than 0.02%, while addition to over 0.3% makes formation of a forsterite film difficult because it impedes oxygen enrichment after decarburization annealing.
  • Mo and Cd also contribute to inhibitor strengthening by forming sulfides and selenides. They have no effect at a content under 0.008%, while when present at over 0.3%, they cause formation of enlarged precipitates that do not function as inhibitors that stabilize the magnetic characteristics.
  • the average diameter of the primary recrystallization grains after completion of decarburization annealing is specified as 18 ⁇ 35 ⁇ m in Japanese Patent Application 06-046161 , for example, in the present invention the average grain diameter of the primary recrystallization grains must be not less than 7 ⁇ m and less than 15 ⁇ m. This is an extremely important point of the invention as regards achieving excellent magnetic characteristics (particularly iron loss property).
  • One reason for this is that, from the viewpoint of grain growth, the volume fraction of Goss oriented grains that can grow as secondary recrystallization grains becomes greater at the primary recrystallization stage when the primary recrystallization grain diameter is smaller ( Materials Science Forum, Vol. 204 ⁇ 206, Part 2, p. 631 ).
  • the secondary recrystallization starts early at the temperature of heating stage (at a low-temperature point) of the final finish annealing.
  • the magnetic characteristics are highly stable.
  • the present invention requires that the steel sheet be nitrided between the completion of the decarburization annealing and the start of secondary recrystallization.
  • This can be achieved either by the method of mixing nitrides (CrN, MnN and the like) with the annealing separator used during high-temperature annealing or by the method of nitriding the decarburization-annealed sheet as a running strip in an atmosphere containing ammonia. While either method can be used, the latter exhibits better stability in industrial production.
  • the amount of nitridation is below 0.001%, the secondary recrystallization is unstable, and when it is over 0.020%, many defects exposing the matrix occur in the glass film.
  • the preferred range is 0.005 ⁇ 0.015%.
  • the slab heating temperature prior to hot rolling is an important factor in this invention. Ultra-high temperature slab heating to a temperature exceeding 1350°C encounters severe difficulties in industrial production. Below the lower limit of 1050°C, on the other hand, the hot rolling becomes practically difficult and, moreover, the generation of primary inhibitor, a key point of the present invention, falls to an insufficient level that causes the primary recrystallization grain diameter to vary greatly with the decarburization annealing temperature. From the viewpoint of ease of hot rolling and the shape (crown) of the hot-rolled strip, the preferred slab heating temperature range is 1200 ⁇ 1300°C.
  • the hot rolling temperature is, moreover, prescribed as: 850 + 2500 ⁇ S ⁇ e ⁇ q + 400 ⁇ M ⁇ N ⁇ F ⁇ O ⁇ T ⁇ starting ⁇ temperature o ⁇ f finishing ⁇ h ⁇ o ⁇ t - rolling ⁇ 1100 + 3000 ⁇ S ⁇ E ⁇ Q + 800 ⁇ M ⁇ n ⁇ 1350 ⁇ ° ⁇ C 800 + 2500 ⁇ S ⁇ e ⁇ q + 400 ⁇ M ⁇ N ⁇ F ⁇ T ⁇ finishing ⁇ temperature o ⁇ f finishing ⁇ h ⁇ o ⁇ t - rolling ⁇ 1050 + 3000 ⁇ S ⁇ E ⁇ Q + 800 ⁇ M ⁇ n ⁇ 1350 ⁇ ° ⁇ C
  • a slab is first produced by the conventional continuous casting method to have an initial thickness in the range of 150 mm to 300 mm, preferably 200 mm to 250 mm. It is also possible instead to use a so-called thin slab with an initial thickness in the range between about 30 mm and 70 mm. These ranges are advantageous in that no roughing rolling down to an intermediate thickness is needed at the time of producing the hot-rolled strip. If a slab or strip is produced beforehand by strip casting, moreover, a grain-oriented electrical steel sheet can be produced by the invention using a slab or strip having an even thinner initial thickness.
  • the heating method adopted for the hot rolling in industrial production is not limited to ordinary gas heating but can instead be induction heating or direct electric heating. No problem is encountered when the shape needed for these special heating methods is obtained by effecting breakdown on the cast slab. When the heating temperature is high, i.e., over 1300°C, this breakdown can be used to improve the texture and lower the amount of C. These are known techniques in the art.
  • the final cold rolling reduction ratio when the final cold rolling reduction ratio is under 80%, the ⁇ 110 ⁇ 001> texture broadens to the point of making it impossible to obtain high magnetic flux density.
  • a final cold rolling reduction ratio of over 92% reduces the ⁇ 110 ⁇ 001> texture to such an extremely low level that the secondary recrystallization becomes unstable.
  • the annealing of the hot-rolled strip is conducted mainly for the purpose of eliminating the nonuniformity of the texture/inhibitor dispersion that occurs in the strip during hot rolling.
  • the annealing can be effected on the hot-rolled strip or be effected prior to the final cold rolling.
  • At least one continuous annealing is preferably conducted before the final cold rolling in order to even out the heat hysteresis that arises during hot rolling.
  • the final cold rolling can be conducted at normal temperature, holding the strip the temperature range of 100 ⁇ 300°C for at least one minute during at least one final cold rolling pass improves the primary recrystallization texture and markedly enhances the magnetic characteristics.
  • heating rate between room temperature and 650 ⁇ 950°C in the decarburization annealing not less than 100°C/sec improves the primary recrystallization texture and enhances the magnetic characteristics.
  • Various methods are available for securing the heating rate. These include resistance heating, induction heating, and direct energy transfer heating. It is known from JP-B-(examined published Japanese patent application) 6-51887 , among others, that speeding up the heating rate increases the Goss orientation in the primary recrystallization texture and reduces the secondary recrystallization grain diameter. While JP-B-6-51887 specifices a heating rate of not less than 40°C/sec, in the present invention the heating rate is effective even at 100°C/sec and is preferably 150°C/sec or higher.
  • the decarburization annealing temperature is specified as not lower than 650°C because the effect is low below this temperature owing to incomplete recrystallization, and is specified as not higher than 950°C because decarburization annealing temperatures in excess of 950°C are not used in the production of grain-oriented electrical steel sheet.
  • Table 1 shows the composition of molten steels produced by an ordinary method
  • Table 2 shows the production conditions and the resulting product characteristics.
  • Continuous annealing was conducted at 1100°C for 150 seconds followed by cooling at 20°C/sec.
  • Annealing was then conducted at 850°C for 90 ⁇ 150 seconds in a mixed atmosphere of H 2 and N 2 having a dew point of 65°C.
  • This decarburization annealing was conducted at different heating rates of 50°C/sec, 110°C/sec and 180°C/sec.
  • Nitriding by the designated method before and after coating with an annealing separator composed mainly of MgO and secondary recrystallization annealing were then conducted.
  • Nitriding method A: Nitriding of running strip B : Addition of MnN to annealing separator
  • Fig. 1 shows the glass film defect rate when production was carried out under the following conditions using a material having the compositions set out below.
  • Each was heated to 1200 ⁇ 1300°C, formed into a 2.3 mm-thick hot-rolled strip, subjected to hot-rolled strip annealing at 980°C for 120 sec, pickled, cold-rolled to a sheet thickness of 1.55 mm, annealed at 1100°C for 150 sec, and final cold-rolled to a sheet thickness of 0.23 mm.
  • the sheet was held at 180 ⁇ 220°C for not less than 2 min in at least two passes.
  • the decarburization annealing temperature has to be changed to obtain primary recrystallization grains of uniform diameter, the oxide layer is not constant, and the glass film defect rate varies and is poor in absolute value.
  • the decarburization annealing temperature can be constant, the oxide layer is substantially constant, and the glass film defect rate is good and stable.
  • Figs. 2 and 3 show how the magnetic characteristics differed depending on whether or not nitriding was conducted in the case of sheets of 0.23 mm and 0.27 mm thickness.
  • the strip was subjected to hot-rolled strip annealing at 980°C for 120 seconds, pickled, cold-rolled to a sheet thickness of 1.55 mm, annealed at 1100°C for 150 seconds, and final cold-rolled to the sheet thickness of 0.23 mm.
  • the strip was subjected to hot-rolled strip annealing at 1120°C for 120 seconds, pickled, and final cold-rolled to the sheet thickness of 0.27 mm.
  • Both nitrided (0.005 ⁇ 0.013% nitriding on a running strip in an ammonia atmosphere) and un-nitrided 0.23 mm sheets and 0.27 mm sheets were produced.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Electromagnetism (AREA)
  • Manufacturing & Machinery (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Manufacturing Of Steel Electrode Plates (AREA)

Claims (8)

  1. Verfahren zur Herstellung eines kornorientierten Elektrostahlblechs mit den folgenden Schritten: auf eine Temperatur im Bereich von 1260 °C bis 1350 °C erfolgendes Nachwärmen einer Bramme, die in Gew.-% aufweist: 0,025 bis 0,10 % C, 2,5 bis 4,0 % Si, 0,010 bis 0,035 % säurelösliches Al, 0,0030 bis 0,010 % N, Seq = (S + 0,406 Se) von 0,008 bis 0,05 %, 0,02 bis 0,20 % Mn, 0,02 bis 0,30 % Cr, optional mindestens einen Bestandteil, ausgewählt aus 0,02 bis 0,30 % Sn, Sb und/oder P, 0,01 bis 0,30 % Cu, 0,03 bis 0,30 % Ni und 0,008 bis 0,3 % Mo und/oder Cd und als Rest Eisen sowie unvermeidliche Verunreinigungen, Warmwalzen der Bramme zu einem warmgewalzten Band, optionales Glühen des warmgewalzten Bands, einmaliges Kaltwalzen oder zwei- oder mehrmaliges Kaltwalzen des warmgewalzten Bands mit Zwischenglühen, um eine Fertigblechdicke zu bilden, Entkohlungsglühen des kaltgewalzten Blechs, Beschichten des Blechs mit einem sich hauptsächlich aus MgO zusammensetzenden Glühseparator und abschließendes Fertigglühen, wobei das Verfahren dadurch gekennzeichnet ist, daß es ferner den Schritt des Nitrierens des Stahlblechs nach dem Entkohlungsglühen und bis zum Beginn der sekundären Rekristallisation aufweist und wobei mindestens ein Bestandteil, der aus Sulfiden und Seleniden ausgewählt ist, als erster Inhibitor verwendet wird und mindestens ein Nitrid, das durch das Nitrieren gebildet wird, als zweiter Inhibitor verwendet wird, und primäre Rekristallisationskörner nach Abschluß des Entkohlungsglühens einen mittleren Korndurchmesser von mindestens 7 µm und höchstens 15 µm haben.
  2. Verfahren zur Herstellung eines kornorientierten Elektrostahlblechs mit den folgenden Schritten: auf eine Temperatur über 1050 °C und unter 1350 °C erfolgendes Nachwärmen einer Bramme mit einer Anfangsdicke von etwa 30 bis 70 mm, die in Gew.-% aufweist: 0,025 bis 0,10 % C, 2,5 bis 4,0 % Si, 0,010 bis 0,035 % säurelösliches Al, 0,0030 bis 0,010 % N, Seq = (S + 0,406 Se) von 0,008 bis 0,05 %, 0,02 bis 0,20 % Mn, 0,02 bis 0,30 % Cr, optional mindestens einen Bestandteil, ausgewählt aus 0,02 bis 0,30 % Sn, Sb und/oder P, 0,01 bis 0,30 % Cu, 0,03 bis 0,30 % Ni und 0,008 bis 0,3 % Mo und/oder Cd und als Rest Eisen sowie unvermeidliche Verunreinigungen, Warmwalzen der Bramme zu einem warmgewalzten Band, optionales Glühen des warmgewalzten Bands, einmaliges Kaltwalzen oder zwei- oder mehrmaliges Kaltwalzen des warmgewalzten Bands mit Zwischenglühen, um eine Fertigblechdicke zu bilden, Entkohlungsglühen des kaltgewalzten Blechs, Beschichten des Blechs mit einem sich hauptsächlich aus MgO zusammensetzenden Glühseparator und abschließendes Fertigglühen, wobei das Verfahren dadurch gekennzeichnet ist, daß es ferner den Schritt des Nitrierens des Stahlblechs nach dem Entkohlungsglühen und bis zum Beginn der sekundären Rekristallisation aufweist und wobei mindestens ein Bestandteil, der aus Sulfiden und Seleniden ausgewählt ist, als erster Inhibitor verwendet wird und mindestens ein Nitrid, das durch das Nitrieren gebildet wird, als zweiter Inhibitor verwendet wird, wobei die Anfangsdicke einer Bramme für das kornorientierte Elektrostahlblech im Bereich zwischen etwa 30 mm und 70 mm liegt und primäre Rekristallisationskörner nach Abschluß des Entkohlungsglühens einen mittleren Korndurchmesser von mindestens 7 µm und höchstens 15 µm haben.
  3. Verfahren zur Herstellung eines kornorientierten Elektrostahlblechs mit ausgezeichneten magnetischen Kennwerten nach Anspruch 1 oder 2, wobei der Schritt des Nitrierens des Stahlblechs nach Entkohlungsglühen an einem laufenden Band in einer Mischgasatmosphäre durchgeführt wird, die Wasserstoff, Stickstoff und Ammoniak aufweist, um die Menge von Stickstoff im Stahlblech um 0,001 bis 0,020 Gew.-% zu erhöhen.
  4. Verfahren zur Herstellung eines kornorientierten Elektrostahlblechs mit ausgezeichneten magnetischen Kennwerten nach einem der Ansprüche 1 bis 3, wobei die Erwärmung beim Entkohlungsglühen mit einer Erwärmungsgeschwindigkeit von mindestens 100 °C/s vom Beginn des Temperaturanstiegs auf 650 bis 950 °C durchgeführt wird.
  5. Verfahren zur Herstellung eines kornorientierten Elektrostahlblechs mit ausgezeichneten magnetischen Kennwerten nach einem der Ansprüche 1 bis 4, wobei die Bandtemperatur auf Temperaturen in den folgenden Bereichen beim Warmwalzen eingestellt wird: 850 + 2500 × Seq + 400 × Mn ≤ FOT °C ≤ 1100 + 3000 × Seq + 800 × Mn ≤ 1350 ⁢ °C
    Figure imgb0007
     wobei FOT: Anfangstemperatur des Fertigwarmwalzens (°C), 850 + 2500 × Seq + 400 × Mn ≤ FT °C ≤ 1050 + 3000 × Seq + 800 × Mn ≤ 1350 ⁢ °C
    Figure imgb0008
     wobei FT: Abschlußtemperatur des Fertigwarmwalzens (°C).
  6. Verfahren zur Herstellung eines kornorientierten Elektrostahlblechs mit ausgezeichneten magnetischen Kennwerten nach einem der Ansprüche 1 bis 5, wobei die Glühbedingungen für das warmgewalzte Band auf eine maximale Temperatur von 950 bis 1150 °C und eine Glühdauer von mindestens 30 Sekunden und höchstens 600 Sekunden eingestellt sind.
  7. Verfahren zur Herstellung eines kornorientierten Elektrostahlblechs mit ausgezeichneten magnetischen Kennwerten nach einem der Ansprüche 1 bis 6, wobei das Kaltwalzen mit einem Dickenabnahmeverhältnis beim Fertigkaltwalzen von 80 bis 92 % durchgeführt wird.
  8. Verfahren zur Herstellung eines kornorientierten Elektrostahlblechs mit ausgezeichneten magnetischen Kennwerten nach einem der Ansprüche 1 bis 7, wobei das Band im Temperaturbereich von 100 bis 300 °C für mindestens 1 min während mindestens eines Fertigkaltwalzdurchgangs des Kaltwalzens gehalten wird.
EP99105071.7A 1998-03-30 1999-03-23 Verfahren zur Herstellung eines kornorientierten Elektrobleches mit ausgezeichneten magnetischen Eigenschaften Expired - Lifetime EP0947597B2 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
DE69923102.7T DE69923102T3 (de) 1998-03-30 1999-03-23 Verfahren zur Herstellung eines kornorientierten Elektrobleches mit ausgezeichneten magnetischen Eigenschaften

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
JP8400798 1998-03-30
JP8400798 1998-03-30
JP30750798 1998-10-28
JP30750798 1998-10-28

Publications (4)

Publication Number Publication Date
EP0947597A2 EP0947597A2 (de) 1999-10-06
EP0947597A3 EP0947597A3 (de) 2001-01-31
EP0947597B1 EP0947597B1 (de) 2005-01-12
EP0947597B2 true EP0947597B2 (de) 2015-06-10

Family

ID=26425094

Family Applications (1)

Application Number Title Priority Date Filing Date
EP99105071.7A Expired - Lifetime EP0947597B2 (de) 1998-03-30 1999-03-23 Verfahren zur Herstellung eines kornorientierten Elektrobleches mit ausgezeichneten magnetischen Eigenschaften

Country Status (3)

Country Link
EP (1) EP0947597B2 (de)
KR (1) KR19990078406A (de)
DE (1) DE69923102T3 (de)

Families Citing this family (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20010064942A (ko) * 1999-12-20 2001-07-11 이구택 자기특성이 우수한 방향성 전기강판의 제조방법
KR100501002B1 (ko) * 2000-05-24 2005-07-18 주식회사 포스코 방향성 전기강판의 제조방법
EP1162280B1 (de) * 2000-06-05 2013-08-07 Nippon Steel & Sumitomo Metal Corporation Verfahren zur Herstellung eines kornorientierten Elektrobleches mit ausgezeichneten magnetischen Eigenschaften
KR100501003B1 (ko) * 2000-06-16 2005-07-18 주식회사 포스코 방향성 전기강판의 제조방법
IT1316026B1 (it) 2000-12-18 2003-03-26 Acciai Speciali Terni Spa Procedimento per la fabbricazione di lamierini a grano orientato.
KR100544637B1 (ko) * 2001-12-24 2006-01-24 주식회사 포스코 자기적 성질이 우수한 방향성 전기강판의 제조방법
DE10311215B4 (de) * 2003-03-14 2005-09-15 Thyssenkrupp Electrical Steel Gmbh Verfahren zum Herstellen von kornorientiertem, kaltgewalztem Elektroblech oder -band
KR100721822B1 (ko) * 2005-12-20 2007-05-28 주식회사 포스코 저철손 고자속밀도를 갖는 방향성 전기강판 제조방법
KR100957911B1 (ko) * 2007-12-28 2010-05-13 주식회사 포스코 자성이 우수한 방향성 전기강판 및 그 제조방법
RU2465348C1 (ru) 2008-09-10 2012-10-27 Ниппон Стил Корпорейшн Способ производства листа из электротехнической стали с ориентированным зерном
KR101051743B1 (ko) * 2008-12-03 2011-07-25 주식회사 포스코 자기특성이 우수한 방향성 전기강판 및 그 제조방법
KR101346537B1 (ko) 2009-04-06 2013-12-31 신닛테츠스미킨 카부시키카이샤 방향성 전자기 강판용 강철의 처리 방법 및 방향성 전자기 강판의 제조 방법
DE102011054004A1 (de) 2011-09-28 2013-03-28 Thyssenkrupp Electrical Steel Gmbh Verfahren zum Herstellen eines kornorientierten, für elektrotechnische Anwendungen bestimmten Elektrobands oder -blechs
US9663839B2 (en) 2011-12-16 2017-05-30 Posco Method for manufacturing grain-oriented electrical steel sheet having excellent magnetic properties
KR101521253B1 (ko) * 2012-11-15 2015-05-18 주식회사 포스코 방향성 전기강판 및 그의 제조방법
KR101480498B1 (ko) 2012-12-28 2015-01-08 주식회사 포스코 방향성 전기강판 및 그 제조방법
CZ2014325A3 (cs) * 2014-05-12 2015-11-11 Arcelormittal Ostrava A.S. Pás z orientované transformátorové oceli a způsob jeho výroby
KR101677551B1 (ko) * 2014-12-18 2016-11-18 주식회사 포스코 방향성 전기강판 및 그 제조방법
DE102017220714B3 (de) * 2017-11-20 2019-01-24 Thyssenkrupp Ag Optimierung des Stickstofflevels während der Haubenglühung

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1998008987A1 (en) † 1996-08-30 1998-03-05 Acciai Speciali Terni S.P.A. Process for the production of grain oriented electrical steel strip having high magnetic characteristics, starting from thin slabs
WO1998010104A1 (en) † 1996-09-05 1998-03-12 Acciai Speciali Terni S.P.A. Process for the production of grain oriented electrical steel strip starting from thin slabs
WO1998041659A1 (en) † 1997-03-14 1998-09-24 Acciai Speciali Terni S.P.A. Process for the inhibition control in the production of grain-oriented electrical sheets

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5956522A (ja) * 1982-09-24 1984-04-02 Nippon Steel Corp 鉄損の良い一方向性電磁鋼板の製造方法
JPS6240315A (ja) * 1985-08-15 1987-02-21 Nippon Steel Corp 磁束密度の高い一方向性珪素鋼板の製造方法
JPH0717961B2 (ja) * 1988-04-25 1995-03-01 新日本製鐵株式会社 磁気特性、皮膜特性ともに優れた一方向性電磁鋼板の製造方法
DE69030771T2 (de) * 1989-01-07 1997-09-11 Nippon Steel Corp Verfahren zum Herstellen eines kornorientierten Elektrostahlbandes
JPH0832929B2 (ja) * 1989-01-07 1996-03-29 新日本製鐵株式会社 磁気特性の優れた一方向性電磁鋼板の製造方法
JPH03189964A (ja) * 1989-12-20 1991-08-19 Matsushita Electric Ind Co Ltd データ再生装置
DE4311151C1 (de) * 1993-04-05 1994-07-28 Thyssen Stahl Ag Verfahren zur Herstellung von kornorientierten Elektroblechen mit verbesserten Ummagnetisierungsverlusten
US5643370A (en) * 1995-05-16 1997-07-01 Armco Inc. Grain oriented electrical steel having high volume resistivity and method for producing same

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1998008987A1 (en) † 1996-08-30 1998-03-05 Acciai Speciali Terni S.P.A. Process for the production of grain oriented electrical steel strip having high magnetic characteristics, starting from thin slabs
WO1998010104A1 (en) † 1996-09-05 1998-03-12 Acciai Speciali Terni S.P.A. Process for the production of grain oriented electrical steel strip starting from thin slabs
WO1998041659A1 (en) † 1997-03-14 1998-09-24 Acciai Speciali Terni S.P.A. Process for the inhibition control in the production of grain-oriented electrical sheets

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
F. BÖLLING ET AL.: "Trends in the development of grain-oriented electrical sheet", vol. 63, 1992, VERLAG STAHLEISEN MBH, DÜSSELDORF, pages: 408 - 412 †

Also Published As

Publication number Publication date
EP0947597A3 (de) 2001-01-31
EP0947597B1 (de) 2005-01-12
DE69923102D1 (de) 2005-02-17
DE69923102T2 (de) 2005-12-29
EP0947597A2 (de) 1999-10-06
KR19990078406A (ko) 1999-10-25
DE69923102T3 (de) 2015-10-15

Similar Documents

Publication Publication Date Title
JP3172439B2 (ja) 高い体積抵抗率を有する粒子方向性珪素鋼およびその製造法
EP0947597B2 (de) Verfahren zur Herstellung eines kornorientierten Elektrobleches mit ausgezeichneten magnetischen Eigenschaften
US6444051B2 (en) Method of manufacturing a grain-oriented electromagnetic steel sheet
EP1501951B2 (de) Verfahren zum kontinuierlichen giessen von nichtorientiertem elektrostahlband
EP1179603B1 (de) Verfahren zur Herstellung eines kornorientierten Elektrobleches mit hoher magnetischer Flussdichte
JP3481491B2 (ja) 磁気特性に優れた一方向性電磁鋼板の製造方法
EP0392534B1 (de) Verfahren zur Herstellung von kornorientierten Elektrostahlblechen mit hervorragenden magnetischen Eigenschaften
EP0539858B1 (de) Verfahren zur Herstellung kornorientierter elektrischer Stahlbänder mit magnetischer Permeabilität
EP1162280A2 (de) Verfahren zur Herstellung eines kornorientierten Elektrobleches mit ausgezeichneten magnetischen Eigenschaften
KR930001330B1 (ko) 자속밀도가 높은 일방향성 전자강판의 제조방법
KR930001331B1 (ko) 자속밀도가 높은 일방향성 전자강판의 제조방법
JPH0686631B2 (ja) 磁束密度の高い一方向性電磁鋼板の製造方法
JPS5948934B2 (ja) 高磁束密度一方向性電磁鋼板の製造方法
JP3488181B2 (ja) 磁気特性に優れた一方向性電磁鋼板の製造方法
EP0861914B1 (de) Verfahren zum Herstellen von kornorientiertem Silizium -Chrom-Elektrostahl
EP4174194A1 (de) Herstellungsverfahren für kornorientiertes elektrostahlblech
EP1390550B1 (de) Verfahren zur herstellung von hochpermeablem kornorientiertem elektrostahl
US4319936A (en) Process for production of oriented silicon steel
JPH0686630B2 (ja) 磁束密度の高い一方向性珪素鋼板の製造方法
EP0076109B1 (de) Methode zur Erzeugung von kornorientierten Siliziumstahlblechen mit ausgezeichneten magnetischen Eigenschaften
EP0477384A1 (de) Verfahren zur herstellung von gleichgerichteten stahlblechen mit ausgezeichneten magnetischen eigenschaften
KR100288351B1 (ko) 한단계의 냉간압연공정을 사용하는 표준 결정립 방향성 전기강 제조 방법
US5261971A (en) Process for preparation of grain-oriented electrical steel sheet having superior magnetic properties
EP0392535B2 (de) Verfahren zum Herstellen kornorientierter Elektrobleche mit verbesserten magnetischen Eigenschaften
JP3485409B2 (ja) 一方向性電磁鋼板の製造方法

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 19990421

AK Designated contracting states

Kind code of ref document: A2

Designated state(s): DE FR GB IT

AX Request for extension of the european patent

Free format text: AL;LT;LV;MK;RO;SI

PUAL Search report despatched

Free format text: ORIGINAL CODE: 0009013

AK Designated contracting states

Kind code of ref document: A3

Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE

AX Request for extension of the european patent

Free format text: AL;LT;LV;MK;RO;SI

AKX Designation fees paid

Free format text: DE FR GB IT

17Q First examination report despatched

Effective date: 20021031

GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

GRAL Information related to payment of fee for publishing/printing deleted

Free format text: ORIGINAL CODE: EPIDOSDIGR3

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

RIN1 Information on inventor provided before grant (corrected)

Inventor name: MOGI, HISASHI,C/O NIPPON STEEL CORP. YAWATA WORKS

Inventor name: OHATA, YOSHIFUMI,NIPPON STEEL CORP. YAWATA WORKS

Inventor name: YAMASAKI, KOJI,C/ONIPPON STEEL CORP. YAWATA WORKS

Inventor name: KUROKI, KATSURO,C/O NITTETSU PLANT DESIGNING CORP

Inventor name: FUJII, NORIKAZU,C/ONIPPON STEEL CORP YAWATA WORK

Inventor name: KUMANO, TOMOJI,C/ONIPPON STEEL CORP. YAWATA WORKS

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE FR GB IT

REG Reference to a national code

Ref country code: GB

Ref legal event code: FG4D

REF Corresponds to:

Ref document number: 69923102

Country of ref document: DE

Date of ref document: 20050217

Kind code of ref document: P

PLBI Opposition filed

Free format text: ORIGINAL CODE: 0009260

PLAX Notice of opposition and request to file observation + time limit sent

Free format text: ORIGINAL CODE: EPIDOSNOBS2

26 Opposition filed

Opponent name: THYSSENKRUPP ELECTRICAL STEEL GMBH

Effective date: 20051011

ET Fr: translation filed
PLAF Information modified related to communication of a notice of opposition and request to file observations + time limit

Free format text: ORIGINAL CODE: EPIDOSCOBS2

PLBB Reply of patent proprietor to notice(s) of opposition received

Free format text: ORIGINAL CODE: EPIDOSNOBS3

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: IT

Payment date: 20070528

Year of fee payment: 9

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20080323

APAH Appeal reference modified

Free format text: ORIGINAL CODE: EPIDOSCREFNO

APBM Appeal reference recorded

Free format text: ORIGINAL CODE: EPIDOSNREFNO

APBP Date of receipt of notice of appeal recorded

Free format text: ORIGINAL CODE: EPIDOSNNOA2O

RAP2 Party data changed (patent owner data changed or rights of a patent transferred)

Owner name: NIPPON STEEL & SUMITOMO METAL CORPORATION

APBQ Date of receipt of statement of grounds of appeal recorded

Free format text: ORIGINAL CODE: EPIDOSNNOA3O

REG Reference to a national code

Ref country code: DE

Ref legal event code: R082

Ref document number: 69923102

Country of ref document: DE

Representative=s name: VOSSIUS & PARTNER PATENTANWAELTE RECHTSANWAELT, DE

Effective date: 20130227

Ref country code: DE

Ref legal event code: R082

Ref document number: 69923102

Country of ref document: DE

Representative=s name: VOSSIUS & PARTNER, DE

Effective date: 20130227

Ref country code: DE

Ref legal event code: R081

Ref document number: 69923102

Country of ref document: DE

Owner name: NIPPON STEEL & SUMITOMO METAL CORPORATION, JP

Free format text: FORMER OWNER: NIPPON STEEL CORP., TOKIO/TOKYO, JP

Effective date: 20130227

APBU Appeal procedure closed

Free format text: ORIGINAL CODE: EPIDOSNNOA9O

PUAH Patent maintained in amended form

Free format text: ORIGINAL CODE: 0009272

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: PATENT MAINTAINED AS AMENDED

27A Patent maintained in amended form

Effective date: 20150610

AK Designated contracting states

Kind code of ref document: B2

Designated state(s): DE FR GB IT

REG Reference to a national code

Ref country code: DE

Ref legal event code: R102

Ref document number: 69923102

Country of ref document: DE

REG Reference to a national code

Ref country code: FR

Ref legal event code: PLFP

Year of fee payment: 18

REG Reference to a national code

Ref country code: FR

Ref legal event code: PLFP

Year of fee payment: 19

REG Reference to a national code

Ref country code: FR

Ref legal event code: PLFP

Year of fee payment: 20

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20180313

Year of fee payment: 20

Ref country code: GB

Payment date: 20180321

Year of fee payment: 20

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20180223

Year of fee payment: 20

REG Reference to a national code

Ref country code: DE

Ref legal event code: R071

Ref document number: 69923102

Country of ref document: DE

REG Reference to a national code

Ref country code: GB

Ref legal event code: PE20

Expiry date: 20190322

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF EXPIRATION OF PROTECTION

Effective date: 20190322