公开(公告)号：US20170283903A1

公开(公告)日：2017-10-05

申请号：US15631577

申请日：2017-06-23

Applicant: SMS Group GmbH

Inventor： Andreas Boettcher ,  Christian Klinkenberg ,  Ingo Schuster

IPC: C21D9/52 ,  C23C8/26 ,  C21D1/42 ,  C21D3/04 ,  C22C38/02 ,  C22C38/50 ,  C22C38/42 ,  C22C38/06 ,  C22C38/04 ,  C22C38/00 ,  C21D8/12 ,  C23F17/00

CPC classification number: C21D9/52 ,  C21D1/42 ,  C21D3/04 ,  C21D6/005 ,  C21D6/008 ,  C21D8/1205 ,  C21D8/1222 ,  C21D8/1233 ,  C21D8/1255 ,  C21D8/1261 ,  C21D8/1272 ,  C21D8/1283 ,  C22C38/001 ,  C22C38/002 ,  C22C38/008 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/16 ,  C22C38/42 ,  C22C38/50 ,  C23C8/02 ,  C23C8/26 ,  C23C8/80 ,  C23F17/00 ,  H01F1/14766 ,  H01F1/16 ,  Y02P10/253

Abstract: A process for producing grain-oriented electrical steel strip by means of thin slab continuous casting, comprising the following process steps: a) smelting a steel, b) continuously casting the smelt by thin slab continuous casting, c) heating up the thin slabs and subjecting the slabs to homogenization annealing at a maximum temperature of 1250° C., d) heating to a temperature between 1250° C. and 1350° C., e) continuously hot rolling the thin slabs to form a hot-rolled strip, f) cooling and reeling the hot-rolled strip to form a coil, g) annealing the hot-rolled strip after reeling and prior to a subsequent cold rolling step, h) cold rolling the hot-rolled strip to the nominal usable thickness, i) subjecting the cold-rolled strip to recrystallization, decarburization and nitridation annealing, j) applying an annealing separator (non-stick layer) to the strip surface of the cold-rolled strip, k) subjecting the cold-rolled strip to secondary recrystallization annealing, forming a finished steel strip having a pronounced Goss texture, and l) stress-free annealing the finished steel strip, which has been coated with an insulating layer, provides an improved process for producing grain-oriented electrical steel strip by means of thin slab continuous casting. This is achieved in that the recrystallization, decarburization and nitridation annealing of the cold-rolled strip in process step h) comprises a decarburization annealing phase and a subsequent nitridation annealing phase, with an intermediate reduction annealing phase being interposed between the decarburization annealing phase and the nitridation annealing phase, and carried out at a temperature ranging from 820° C.-890° C., for a maximum period of 40 seconds, with a dry, gaseous annealing atmosphere, which contains nitrogen (N2) and hydrogen (H2) and acts on the cold-rolled strip, and which has a water vapor/hydrogen partial pressure ratio pH2O/pH2 of less than 0.10.

公开(公告)号：US20170275729A1

公开(公告)日：2017-09-28

申请号：US15518604

申请日：2015-10-15

Applicant: SMS Group GmbH

Inventor： Ingo Schuster

IPC: C21D9/46 ,  C21D8/02 ,  B21B1/22 ,  C21D9/00

CPC classification number: C21D9/46 ,  B21B1/22 ,  B21B1/26 ,  B21B1/463 ,  B21B37/74 ,  B21B2001/225 ,  B22D11/14 ,  C21D8/0205 ,  C21D8/0226 ,  C21D8/0263 ,  C21D9/0062 ,  C21D2211/001 ,  C21D2211/002 ,  C21D2211/005 ,  C21D2211/008

Abstract: In the context of a method for producing heavy plate (4) from a steel alloy, comprising the continuous casting of a steel melt and primary forming of an obtained casting strand to produce a slab, and then forming or hot rolling the slab from the casting heat in multiple forming steps to produce a desired heavy plate dimension, followed immediately by a heat treatment of the heavy plate (4), effecting a targeted cooling of the obtained heavy plate (4), wherein the heavy plate (4) is cut to a desired individual plate length before or after its heat treatment as seen in the production direction (3), a solution is provided for producing heavy plate that permits the flexible production of heavy plate of variable qualities. This is achieved by carrying out the heat treatment in the temperature range of 150° C.-1100° C. as a combination of a targeted cooling of the obtained heavy plate (4) from the rolling heat to a desired first temperature, followed immediately by a targeted heating of the heavy plate (4) to a desired second temperature and an immediately subsequent cooling of the heavy plate (4) to a desired third temperature.

公开(公告)号：US11239012B2

公开(公告)日：2022-02-01

申请号：US14638338

申请日：2015-03-04

Applicant: SMS Group GmbH

Inventor： Andreas Boettcher ,  Christian Klinkenberg ,  Ingo Schuster

IPC: C21D1/42 ,  H01F1/147 ,  C21D8/12 ,  C21D3/04 ,  C21D6/00 ,  C21D9/52 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/16 ,  C23C8/02 ,  C23C8/26 ,  H01F41/02

Abstract: A process for producing grain-oriented electrical steel strip by means of thin slab continuous casting and which includes continuously casting the smelt by thin slab continuous casting, subjecting the thin slabs to homogenization annealing at a maximum temperature of 1250° C. and heating to a temperature between 1350° C. and 1380° C., and continuously hot rolling the thin slabs to form a hot-rolled strip, with cooling and reeling the hot-rolled strip to form a coil and cold rolling the hot-rolled strip to a nominal thickness, with subjecting the cold-rolled strip to recrystallization, decarburization and nitridation annealing, which includes a decarburization annealing phase and a subsequent nitridation annealing phase, with an intermediate reduction annealing phase being interposed between the decarburization annealing phase and the nitridation annealing phase, whereby a cold-rolled strip is obtained, which primary recrystallized grains have a circle equivalent mean size (diameter) between 22 μm and 25 μm.

公开(公告)号：US20250146753A1

公开(公告)日：2025-05-08

申请号：US18684231

申请日：2022-08-17

Applicant: SMS group GmbH

Inventor： Hans Ferkel ,  Markus Reifferscheid ,  Thomas Henkel ,  Ingo Schuster

IPC: F27B3/28 ,  F27D19/00 ,  F27D21/00

Abstract: The invention relates to an electric arc furnace having a furnace vessel with at least one electrode and a voltage supply connected to the at least one electrode, wherein: the furnace vessel has a lower vessel for receiving a melt and a cover for placing onto the lower vessel; the lower vessel has a tapping channel; and the cover has a retaining means for fastening the at least one electrode; the electric arc furnace is designed to determine a nitrogen content in the melt; and/or the electric arc furnace is designed to reduce the nitrogen content in the melt to less than or equal to 55 ppm, preferably to less than or equal to 45 ppm and particularly preferably to less than or equal to 35 ppm. The invention further relates to an operating method and to a use of an electric arc furnace.