公开(公告)号：US20230321706A1

公开(公告)日：2023-10-12

申请号：US18043044

申请日：2021-08-16

Applicant: JFE STEEL CORPORATION

Inventor： Mayumi OJIMA ,  Yoshimasa FUNAKAWA

IPC: B21C51/00

CPC classification number: B21C51/00

Abstract: Provided is a steel strip that can provide accurate material information and a method of producing the same. A steel strip (9) comprises a medium that provides material information including a material distribution associating each position in a two-dimensional direction of a rolling direction and a transverse direction with a material characteristic value. The material information is predicted using a prediction model to which input data including a line output factor in a production line for the steel strip, a disturbance factor, and a component value of the steel strip being produced is input. The prediction model includes: a machine learning model that receives the input data as input and outputs a production condition factor and that is generated by machine learning; and a metallurgical model that receives the production condition factor as input and outputs the material characteristic value.

公开(公告)号：US20210147957A1

公开(公告)日：2021-05-20

申请号：US17158097

申请日：2021-01-26

Applicant: JFE Steel Corporation

Inventor： Hidekazu MINAMI ,  Yoshimasa FUNAKAWA

IPC: C21D9/46 ,  C23C2/06 ,  C22C38/60 ,  C25D5/50 ,  C23C2/40 ,  C23C2/12 ,  C23C2/28 ,  C25D7/06 ,  C22C38/30 ,  C22C38/32 ,  C22C38/52 ,  C21D6/00 ,  C22C38/16 ,  C23C30/00 ,  C22C38/28 ,  C22C38/48 ,  C22C38/40 ,  C22C38/22 ,  C22C38/24 ,  C22C38/54 ,  C22C38/42 ,  C22C38/26 ,  C23C2/00 ,  C22C38/18 ,  C22C38/44 ,  C22C38/50 ,  C23C2/04 ,  C22C38/46 ,  B32B15/01 ,  B32B15/04 ,  B32B15/18 ,  C21D8/02 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/08 ,  C22C38/10 ,  C22C38/12 ,  C22C38/14 ,  C22C38/20

Abstract: A method of producing a hot-rolled steel sheet and a method for producing a cold-rolled full hard steel sheet are provided. The methods comprising heating a steel slab having a composition containing, in terms of mass %, C: 0.010% or more and 0.150% or less, Si: 0.20% or less, Mn: 1.00% or less, P: 0.100% or less, S: 0.0500% or less, Al: 0.001% or more and 0.100% or less, N: 0.0100% or less, and the balance being Fe and unavoidable impurities, in which 0.002%≤[%P]+[%S ]≤0.070% ([%M] denotes a content (mass %) of M element in steel) is satisfied.

公开(公告)号：US20190040489A1

公开(公告)日：2019-02-07

申请号：US16073905

申请日：2017-01-26

Applicant: JFE STEEL CORPORATION

Inventor： Hiroshi HASEGAWA ,  Yoshimasa FUNAKAWA

IPC: C21D9/46 ,  C21D8/02 ,  C21D6/00 ,  C22C38/14 ,  C22C38/12 ,  C22C38/60 ,  C22C38/38 ,  C22C38/24 ,  C22C38/28 ,  C22C38/16 ,  C22C38/08 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/00 ,  C23C2/06 ,  C23C2/40 ,  C23C2/26 ,  C23F17/00

Abstract: A high-strength steel sheet for warm working having excellent warm workability, and a method for manufacturing the steel sheet. The steel sheet has a chemical composition including, by mass %, C: 0.05% to 0.20%, Si: 3.0% or less, Mn: 3.5% to 8.0%, P: 0.100% or less, S: 0.02% or less, Al: 0.01% to 3.0%, N: 0.010% or less, one or more selected from Nb: 0.005% to 0.20%, Ti: 0.005% to 0.20%, Mo: 0.005% to 1.0%, and V: 0.005% to 1.0%. The steel sheet has a microstructure including, in terms of area ratio, 10% to 60% of retained austenite, 10% to 80% of ferrite, 10% to 50% of martensite, and 0% to 5% of bainite, in which a C content in the retained austenite is less than 0.40 mass % and the average crystal grain diameter of the retained austenite, the martensite, and the ferrite is 2.0 μm or less.

公开(公告)号：US20180237880A1

公开(公告)日：2018-08-23

申请号：US15554591

申请日：2016-01-14

Applicant: JFE STEEL CORPORATION

Inventor： Noriaki KOHSAKA ,  Yoshimasa FUNAKAWA ,  Michitaka SAKURAI ,  Yoshikazu SUZUKI

IPC: C21D9/46 ,  C21D8/02 ,  C21D6/00 ,  C22C38/60 ,  C22C38/14 ,  C22C38/12 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/00 ,  C23C2/40 ,  C23C2/28 ,  C23C2/06 ,  C22C18/04

CPC classification number: C21D9/46 ,  C21D6/005 ,  C21D6/008 ,  C21D8/0205 ,  C21D8/0226 ,  C21D8/0236 ,  C21D8/0263 ,  C21D8/0278 ,  C22C18/00 ,  C22C18/04 ,  C22C38/00 ,  C22C38/001 ,  C22C38/002 ,  C22C38/005 ,  C22C38/008 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/12 ,  C22C38/14 ,  C22C38/60 ,  C23C2/06 ,  C23C2/28 ,  C23C2/40

Abstract: A high-strength steel sheet having a composition containing C: 0.09% to 0.17%, Si: 0.6% to 1.7%, Mn: 3.5% or less, P: 0.03% or less, S: 0.005% or less, Al: 0.08% or less, N: 0.006% or less, Ti: 0.05% or less, and B: 0.0002% to 0.0030% on a mass basis, the remainder being Fe and inevitable impurities. The steel sheet also has a microstructure containing less than 20% (including 0%) of a ferrite phase, 75% or more (including 100%) of a tempered martensite phase, 10% or less (including 0%) of an untempered martensite phase, and less than 5% (including 0%) of a retained austenite phase in terms of area fraction. The tempered martensite phase has a Vickers hardness of 280 to 340 and a tensile strength of 950 MPa to 1,120 MPa.

公开(公告)号：US20230323503A1

公开(公告)日：2023-10-12

申请号：US18043579

申请日：2021-08-16

Applicant: JFE STEEL CORPORATION

Inventor： Mayumi OJIMA ,  Yoshimasa FUNAKAWA

IPC: C21D11/00 ,  C21D9/46 ,  C21D8/02 ,  B21B37/76 ,  G05B13/02 ,  G05B13/04

CPC classification number: C21D11/00 ,  C21D9/46 ,  C21D8/0205 ,  C21D8/0263 ,  C21D8/0278 ,  B21B37/76 ,  G05B13/0265 ,  G05B13/048

Abstract: A material characteristic value prediction system that can predict material characteristic values with high accuracy is provided. Also provided is a method of manufacturing a metal sheet that can improve the product yield rate, by changing manufacturing conditions of subsequent processes. The material characteristic value prediction system (100) includes a material characteristic value predictor configured to acquire input data including line output factors in a metal sheet manufacturing line, disturbance factors, and component values of a metal sheet being manufactured, and predict material characteristic values of the manufactured metal sheet using a prediction model configured to take the input data as inputs, wherein the prediction model includes a machine learning model generated by machine learning and configured to take the input data as inputs and output production condition factors, and a metallurgical model configured to take the production condition factors as inputs and output the material characteristic values.

公开(公告)号：US20210108282A1

公开(公告)日：2021-04-15

申请号：US17043514

申请日：2019-03-20

Applicant: JFE STEEL CORPORATION

Inventor： Yoshiyasu KAWASAKI ,  Kazuki ENDO ,  Yuki TOJI ,  Yoshimasa FUNAKAWA ,  Satoshi MAEDA ,  Mai AOYAMA

IPC: C21D9/46 ,  C21D8/02 ,  C21D6/00 ,  C22C38/54 ,  C22C38/50 ,  C22C38/48 ,  C22C38/46 ,  C22C38/44 ,  C22C38/42 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/00 ,  B32B15/01 ,  C23C2/02 ,  C23C2/28 ,  C23C2/40 ,  C23C2/06

Abstract: A high-strength steel includes a steel structure with: in area fraction, 60.0% to less than 90.0% of ferrite, 0% to less than 5.0% of unrecrystallized ferrite, 2.0% to 25.0% of martensite, 0% to 5.0% of carbide, and 0% to 3.0% of bainite; in volume fraction, more than 7.0% of retained austenite; in a cross-sectional view of 100 μm×100 μm, a value obtained by dividing number of retained austenite that are not adjacent to retained austenite whose crystal orientations are different by a total number of retained austenite being less than 0.80, an average crystal grain size of the ferrite being 6.0 μm or less, an average crystal grain size of the retained austenite being 3.0 μm or less, and a value obtained by dividing, by mass %, an average content of Mn in the retained austenite by an average content of Mn in steel being 1.50 or more.

公开(公告)号：US20190127820A1

公开(公告)日：2019-05-02

申请号：US16089928

申请日：2017-01-17

Applicant: JFE STEEL CORPORATION

Inventor： Hiroshi HASEGAWA ,  Yoshimasa FUNAKAWA

IPC: C21D9/46 ,  B32B15/01 ,  C21D8/02 ,  C21D6/00 ,  C23C2/06 ,  C23C2/28 ,  C23C2/40 ,  C22C38/26 ,  C22C38/22 ,  C22C38/16 ,  C22C38/14 ,  C22C38/12 ,  C22C38/60 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/00 ,  C22C38/08

Abstract: A steel sheet, a plated steel sheet, and methods for producing a hot-rolled steel sheet, a cold-rolled full hard steel sheet, and a steel sheet. The steel sheet has a specified composition and a microstructure including 0 to 80% of polygonal ferrite and 20 to 100% of a total of martensite, bainite, and residual austenite in terms of an area ratio within 20 μm of the steel sheet surface. The content of Mn in martensite present within 20 μm of the steel sheet surface ([Mn]SM) and the content of Mn in a bulk ([Mn]B) satisfy [Mn]SM/[Mn]B≤1.5. At a location 300 μm from the steel sheet surface, an area ratio of the martensite is in a range of 20 to 50%.

公开(公告)号：US20160138141A1

公开(公告)日：2016-05-19

申请号：US14778339

申请日：2014-03-11

Applicant: JFE STEEL CORPORATION

Inventor： Katsumi NAKAJIMA ,  Yoshimasa FUNAKAWA ,  Nobuyuki NAKAMURA

IPC: C22C38/50 ,  C22C38/28 ,  C22C38/14 ,  C22C38/00 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/42 ,  C22C38/12

CPC classification number: C22C38/50 ,  B32B15/013 ,  C21D8/1222 ,  C21D8/1261 ,  C21D9/46 ,  C21D2211/002 ,  C21D2211/004 ,  C22C38/00 ,  C22C38/001 ,  C22C38/002 ,  C22C38/005 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/08 ,  C22C38/12 ,  C22C38/14 ,  C22C38/16 ,  C22C38/28 ,  C22C38/42 ,  C22C38/58 ,  C23C2/06 ,  C23C2/40 ,  H01F1/16

Abstract: A high strength hot rolled steel sheet with good formability, which has good magnetic properties, excellent punchability, and a tensile strength of 780 MPa or more. The high strength hot rolled steel sheet having a chemical composition containing C: 0.070% to 0.140%, Si: 0.10% to 1.00%, Mn: 1.00% to 1.80%, P: 0.050% or less, S: 0.0050% or less, N: 0.0080% or less, Al: 0.010% to 0.100%, Ti: 0.050% to 0.150%, and the remainder composed of Fe and incidental impurities, on a percent by mass basis, and 95% or more of bainite microstructure on a volume fraction basis, wherein carbides constituting 80% or more of total precipitation carbides are dispersed at grain boundaries of bainitic ferrite constituting the bainite microstructure and 80% or more of total precipitation carbides have particle grain sizes of 20 to 300 nm.

Abstract translation: 具有良好的成形性的高强度热轧钢板，具有良好的磁性能，优异的冲压性和780MPa以上的拉伸强度。 化学成分为C：0.070〜0.140％，Si：0.10〜1.00％，Mn：1.00〜1.80％，P：0.050％以下，S：0.0050％以下的高强度热轧钢板， N：0.0080％以下，Al：0.010〜0.100％，Ti：0.050〜0.150％，余量由Fe和杂质构成，以质量计为基准，95％以上的贝氏体组织 其中构成总沉淀碳化物的80％以上的碳化物分散在构成贝氏体组织的贝氏体铁素体的晶界处，并且总沉淀碳化物的80％以上的粒子粒径为20〜300nm。

公开(公告)号：US20210010101A1

公开(公告)日：2021-01-14

申请号：US17042291

申请日：2019-03-20

Applicant: JFE STEEL CORPORATION

Inventor： Kazuki ENDO ,  Yoshiyasu KAWASAKI ,  Yuki TOJI ,  Yoshimasa FUNAKAWA ,  Mai AOYAMA

IPC: C21D9/46 ,  C22C38/38 ,  C22C38/28 ,  C22C38/16 ,  C22C38/12 ,  C22C38/08 ,  C22C38/06 ,  C22C38/02 ,  C22C38/00 ,  C21D8/02 ,  C21D6/00 ,  C23C2/02 ,  C23C2/06 ,  C23C2/28 ,  C23C2/40

Abstract: A high-strength steel sheet includes a steel structure with: ferrite being 35% to 80% and tempered martensite being greater than 5% and 20% or less in terms of area fraction; retained austenite being 8% or more in terms of volume fraction; an average grain size of: the ferrite being 6 μm or less; and the retained austenite being 3 μm or less; a value obtained by dividing an area fraction of blocky austenite by a sum of area fractions of lath-like austenite and the blocky austenite being 0.6 or more; a value obtained by dividing, by mass %, an average Mn content in the retained austenite by an average Mn content in the ferrite being 1.5 or more; and a value obtained by dividing, by mass %, an average C content in the retained austenite by an average C content in the ferrite being 3.0 or more.

公开(公告)号：US20200370140A1

公开(公告)日：2020-11-26

申请号：US16620615

申请日：2018-03-30

Applicant: JFE STEEL CORPORATION

Inventor： Katsutoshi TAKASHIMA ,  Takashi KOBAYASHI ,  Yoshimasa FUNAKAWA ,  Seiji NAKAJIMA

IPC: C21D9/46 ,  B32B15/01 ,  C22C38/32 ,  C22C38/28 ,  C22C38/26 ,  C22C38/16 ,  C22C38/10 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/00 ,  C21D8/02 ,  C21D6/00 ,  C21D1/18 ,  C23C30/00 ,  B21D22/02

Abstract: Disclosed is a hot-pressed member that can exhibit very high tensile strength after hot pressing as high as TS: 1780 MPa or more, and excellent indentation peeling strength at projection welds by properly adjusting its chemical composition and its microstructure such that a prior austenite average grain size is 7 μm or less within a range of 50 μm or less in a thickness direction from a surface of the member, a volume fraction of martensite is 90% or more, and an average intergrain distance of Nb and Ti carbonitrides having a grain size of less than 0.10 μm within a depth range of 20 μm to 100 μm in the thickness direction from the surface of the member is 5 μm or less.