公开(公告)号：US10036079B2

公开(公告)日：2018-07-31

申请号：US14774351

申请日：2014-03-05

申请人： JFE STEEL CORPORATION

发明人： Yusuke Terazawa ,  Katsuyuki Ichimiya ,  Kazukuni Hase ,  Shigeru Endo

IPC分类号： C22C38/00 ,  C21D9/46 ,  C21D8/02 ,  C22C38/14 ,  C22C38/58 ,  B23K35/30 ,  C22C38/04 ,  C22C38/08 ,  C21D1/84 ,  C21D6/00 ,  C22C38/02 ,  C22C38/06 ,  C22C38/12 ,  C22C38/16 ,  C22C38/50

CPC分类号： C21D9/46 ,  B23K35/3073 ,  C21D1/84 ,  C21D6/004 ,  C21D6/005 ,  C21D6/008 ,  C21D8/02 ,  C21D8/0205 ,  C21D8/0226 ,  C21D8/0247 ,  C21D8/0263 ,  C21D2211/004 ,  C22C38/001 ,  C22C38/002 ,  C22C38/005 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/08 ,  C22C38/12 ,  C22C38/14 ,  C22C38/16 ,  C22C38/50 ,  C22C38/58

摘要： There is provided a thick steel plate having good multipass weld joint CTOD characteristics for low to medium heat input and a method for manufacturing the thick steel plate. A steel plate containing, on a mass percent basis, C: 0.03% to 0.12%, Si: 0.5% or less, Mn: 1.0% to 2.0%, P: 0.015% or less, S: 0.0005% to 0.0050%, Al: 0.005% to 0.060%, Ni: 0.5% to 2.0%, Ti: 0.005% to 0.030%, N: 0.0015% to 0.0065%, O: 0.0010% to 0.0050%, Ca: 0.0005% to 0.0060%, and optionally one or two or more of Cu and the like, wherein Ti/N, Ceq, Pcm, and ACR are in particular ranges, a base material of the plate has an effective grain size of 20 μm or less at half the thickness of the plate, and the plate contains a particular number of complex inclusions at ¼ and ½ of the thickness of the plate, the complex inclusions being composed of a sulfide containing Ca and Mn and an oxide containing Al and having an equivalent circular diameter of 0.1 μm or more. Steel having the composition described above is heated at a particular temperature, is then hot-rolled, and is cooled.

公开(公告)号：US20170044639A1

公开(公告)日：2017-02-16

申请号：US15304702

申请日：2015-04-24

申请人： JFE Steel Corporation

发明人： Shigeki Kitsuya ,  Katsuyuki Ichimiya ,  Kazukuni Hase ,  Shigeru Endo

IPC分类号： C21D9/46 ,  C22C38/58 ,  C22C38/54 ,  C22C38/50 ,  C22C38/48 ,  C22C38/46 ,  C22C38/44 ,  C22C38/42 ,  C22C38/16 ,  C22C38/14 ,  C22C38/08 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/00 ,  C21D8/02 ,  B21B1/22

CPC分类号： C21D9/46 ,  B21B1/22 ,  B21B1/26 ,  B21B3/00 ,  B21B2001/225 ,  C21D8/02 ,  C21D8/0205 ,  C21D8/0226 ,  C21D8/0263 ,  C21D2211/002 ,  C21D2211/008 ,  C22C38/00 ,  C22C38/001 ,  C22C38/002 ,  C22C38/005 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/08 ,  C22C38/14 ,  C22C38/16 ,  C22C38/42 ,  C22C38/44 ,  C22C38/46 ,  C22C38/48 ,  C22C38/50 ,  C22C38/54 ,  C22C38/58

摘要： A steel plate has excellent strength and toughness in a mid-thickness part thereof, despite having a plate thickness of 100 mm or greater. The steel plate has a chemical composition containing specific amounts of C, Si, Mn, P, S, Cr, Ni, Al, N, B, and 0, with the balance being Fe and incidental impurities, and having an equivalent carbon content Cer of 0.65 or greater. The steel plate has a yield strength of 620 MPa or greater, a plate thickness of 100 mm or greater, and has a microstructure in which prior γ grain size in a mid-thickness part of the steel plate has a maximum value, expressed as an equivalent circle diameter, of 150 μm or less, and a total area ratio of martensite and bainite in the mid-thickness part is 80% or greater.

摘要翻译： 尽管板厚为100mm以上，钢板在其中厚部分具有优异的强度和韧性。 钢板具有含有特定量的C，Si，Mn，P，S，Cr，Ni，Al，N，B和0的化学成分，余量为Fe和附带杂质，具有等效碳含量Cer 为0.65以上。 钢板的屈服强度为620MPa以上，板厚为100mm以上，并且具有以下的微观结构，其中钢板的中间部分中的γ粒径之前为最大值，表示为 当量圆直径为150μm以下，中厚部的马氏体和贝氏体的总面积比为80％以上。

公开(公告)号：US20210140023A1

公开(公告)日：2021-05-13

申请号：US16074184

申请日：2017-01-30

申请人： JFE Steel Corporation

发明人： Yuki Toji ,  Akio Ohmori ,  Koichi Nakashima ,  Ryo Arao ,  Katsuyuki Ichimiya ,  Kazukuni Hase

IPC分类号： C22C38/54 ,  C22C38/00 ,  C22C38/04 ,  C22C38/46 ,  C22C38/42 ,  C22C38/48 ,  C22C38/50 ,  C22C38/06 ,  B23K35/30 ,  C22C38/44

摘要： Provided is a steel material for high heat input welding having excellent welding heat affected zone low-temperature toughness at −55° C. in the case that the steel material is welded by high heat input welding with a heat input of more than 80 kJ/cm. The steel material may be used in low-temperature storage tanks, for example. The steel material for high heat input welding includes, in mass %, C: 0.04 to 0.09%, Si: 0.15 to 0.25%, Mn: 1.40 to 2.00%, P: 0.015% or less, S: 0.0005 to 0.0040%, Al: 0.030 to 0.080%, Ti: 0.005 to 0.025%, B: 0.0003 to 0.0020%, Ca: 0.0005 to 0.0030%, N: 0.0030 to 0.0060%, O: 0.0040% or less, Nb: 0.005% or less, and Mo: 0.005% or less, the balance being Fe and incidental impurities.

公开(公告)号：US10351926B2

公开(公告)日：2019-07-16

申请号：US15525672

申请日：2015-11-17

申请人： JFE STEEL CORPORATION

发明人： Yota Kuronuma ,  Hirofumi Ohtsubo ,  Shigeki Kitsuya ,  Katsuyuki Ichimiya ,  Kazukuni Hase

IPC分类号： C21D9/46 ,  B21J1/02 ,  C22C38/00 ,  C22C38/58 ,  C21D6/00 ,  C21D7/13 ,  C21D8/00 ,  C21D8/02 ,  C21D9/00 ,  C21D1/18 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/08 ,  C22C38/12 ,  C22C38/14 ,  C22C38/20 ,  C22C38/22 ,  C22C38/24 ,  C22C38/26 ,  C22C38/28 ,  C22C38/32 ,  C22C38/42 ,  C22C38/44 ,  C22C38/46 ,  C22C38/48 ,  C22C38/50 ,  C22C38/54 ,  B21J5/02

摘要： A thick steel plate is provided by heating a continuously-cast slab, hot forging the continuously-cast slab using opposing dies having respective short sides differing such that when a short side length of a die having a shorter one of the short sides is taken to be 1, a short side length of a die having a longer one of the short sides is 1.1 to 3.0, allowing cooling to obtain a steel raw material, reheating the steel raw material, performing hot rolling of the steel raw material including at least two passes carried out, allowing cooling to obtain a thick steel plate, reheating the thick steel plate to at least the Ac3 temperature and no higher than 1050° C., rapidly cooling the thick steel plate to 350° C. or lower, and tempering the thick steel plate at at least 550° C. and no higher than 700° C.

公开(公告)号：US10300564B2

公开(公告)日：2019-05-28

申请号：US15129932

申请日：2015-03-31

申请人： JFE STEEL CORPORATION

发明人： Katsuyuki Ichimiya ,  Masao Yuga ,  Kazukuni Hase ,  Shigeru Endo

IPC分类号： B23K35/30 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/08 ,  C22C38/14 ,  C22C38/42 ,  C22C38/44 ,  C22C38/46 ,  C22C38/48 ,  C22C38/50 ,  C22C38/54 ,  C22C38/58 ,  C21D9/18 ,  C21D9/30 ,  C21D9/50 ,  F16B5/08 ,  B23K9/23 ,  B23K9/18 ,  B23K103/04

摘要： A weld joint with an excellent CTOD property is produced with a weld metal, using a steel plate as a base metal. The steel plate has a chemical composition including C: 0.03% to 0.09%, Si: 0.01% to 0.35%, Mn: 1.3% to 2.0%, P: 0.012% or less, S: 0.0035% or less, Al: 0.01% to 0.06%, Ni: less than 0.3%, Mo: less than 0.10%, Nb: 0.005% to 0.023%, Ti: 0.005% to 0.025%, B: less than 0.0003%, N: 0.002% to 0.005%, Ca: 0.0005% to 0.0050%, and O: 0.0030% or less, with the components additionally satisfying a predetermined relationship. The weld metal has a chemical composition including C: 0.040% to 0.090%, Si: 0.1% to 0.8%, Mn: 1.0% to 2.5%, Al: 0.020% or less, Ni: 0.1% to 1.0%, Mo: 0.05% to 0.50%, Ti: 0.005% to 0.050%, and B: 0.0015% or less, the balance being Fe and incidental impurities.

公开(公告)号：US10000833B2

公开(公告)日：2018-06-19

申请号：US14770853

申请日：2014-03-11

申请人： JFE Steel Corporation

发明人： Shigeki Kitsuya ,  Naoki Matsunaga ,  Katsuyuki Ichimiya ,  Kazukuni Hase ,  Shigeru Endo

IPC分类号： C22C38/50 ,  C22C38/58 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/42 ,  C22C38/44 ,  C22C38/46 ,  C22C38/54 ,  C21D1/78 ,  C21D6/00 ,  C21D8/02 ,  C22C38/08 ,  C22C38/12 ,  C22C38/14 ,  C22C38/16 ,  C22C38/20 ,  C22C38/22 ,  C22C38/24 ,  C22C38/28 ,  C22C38/32 ,  C22C38/38 ,  C21D1/25

CPC分类号： C22C38/58 ,  C21D1/25 ,  C21D1/78 ,  C21D6/004 ,  C21D6/005 ,  C21D6/008 ,  C21D8/0205 ,  C21D8/021 ,  C21D8/0226 ,  C21D8/0263 ,  C21D2211/001 ,  C21D2211/002 ,  C21D2211/004 ,  C21D2211/008 ,  C22C38/00 ,  C22C38/001 ,  C22C38/002 ,  C22C38/005 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/08 ,  C22C38/12 ,  C22C38/14 ,  C22C38/16 ,  C22C38/20 ,  C22C38/22 ,  C22C38/24 ,  C22C38/28 ,  C22C38/32 ,  C22C38/38 ,  C22C38/42 ,  C22C38/44 ,  C22C38/46 ,  C22C38/50 ,  C22C38/54

摘要： A thick, high-toughness high-strength steel plate has excellent strength and toughness in the central area through the plate thickness. The thick steel plate has a specific chemical composition and includes a microstructure having, throughout an entire region in the plate thickness direction, an average prior austenite grain size of not more than 50 μm and a martensite and/or bainite phase area fraction of not less than 80%. A continuously cast slab having the specific chemical composition is heated to 1200° C. to 1350° C., hot worked with a strain rate of not more than 3/s and a cumulative working reduction of not less than 15%, and thereafter hot rolled and heat treated.

公开(公告)号：US20160040274A1

公开(公告)日：2016-02-11

申请号：US14774366

申请日：2014-03-05

申请人： JFE STEEL CORPORATION

发明人： Yusuke Terazawa ,  Katsuyuki Ichimiya ,  Kazukuni Hase ,  Shigeru Endo

IPC分类号： C22C38/50 ,  C21D9/46 ,  C21D6/00 ,  C22C38/16 ,  C22C38/00 ,  C22C38/12 ,  C22C38/08 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C21D8/02 ,  C22C38/14

CPC分类号： C22C38/50 ,  C21D6/001 ,  C21D6/002 ,  C21D6/005 ,  C21D6/008 ,  C21D8/0226 ,  C21D8/0263 ,  C21D9/46 ,  C22C38/00 ,  C22C38/001 ,  C22C38/002 ,  C22C38/005 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/08 ,  C22C38/12 ,  C22C38/14 ,  C22C38/16 ,  C22C38/18

摘要： Provided are a thick steel plate with which a welded joint having good CTOD property is formed by low-to-medium heat input multipass welding and a method for producing the thick steel plate.The steel plate has a composition containing, by mass, C: 0.03% to 0.10%, Si: 0.5% or less, Mn: 1.0% to 2.0%, P: 0.015% or less, S: 0.0005% to 0.0050%, Al: 0.005% to 0.060%, Ni: 0.5% to 2.0%, Ti: 0.005% to 0.030%, N: 0.0015% to 0.0065%, O: 0.0010% to 0.0050%, Ca: 0.0005% to 0.0060%, and, as needed, one or more elements such as Cu. Ti/N, Ceq, Pcm, and ACR each fall within the specific range. The effective crystal grain size of the base metal at the center of the plate in the thickness direction is 20 μm or less. A specific amount of a composite inclusion including a sulfide containing Ca and Mn and an oxide containing Al having an equivalent circular diameter of 0.1 μm or more is present at the ¼-thickness position and the ½-thickness position of the plate. The steel having the above-described composition is heated to a specific temperature, hot rolled, and cooled.

摘要翻译： 本发明提供一种厚钢板，通过低 - 中加热输入多次焊接形成具有良好CTOD性能的焊接接头，以及生产厚钢板的方法。 该钢板的组成为：含有C：0.03〜0.10％，Si：0.5％以下，Mn：1.0％〜2.0％，P：0.015％以下，S：0.0005〜0.0050％，Al ：0.005〜0.060％，Ni：0.5〜2.0％，Ti：0.005〜0.030％，N：0.0015％〜0.0065％，○：0.0010％〜0.0050％，Ca：0.0005〜0.0060％ 需要，一个或多个元素如Cu。 Ti / N，Ceq，Pcm和ACR分别落在特定范围内。 板厚中心处的母材的有效晶粒尺寸为20μm以下。 存在特定量的包含Ca和Mn的硫化物的复合夹杂物和含有等效圆直径为0.1μm以上的Al的氧化物存在于板的1/4厚度位置和1/2厚度位置。 将具有上述组成的钢加热到特定温度，热轧并冷却。

公开(公告)号：US11332799B2

公开(公告)日：2022-05-17

申请号：US16330857

申请日：2017-09-08

申请人： JFE STEEL CORPORATION

发明人： Keisuke Ando ,  Takashi Iwamoto ,  Kimihiro Nishimura ,  Katsuyuki Ichimiya

IPC分类号： C21D1/06 ,  C21D9/32 ,  C22C38/00 ,  C21D9/00 ,  C21D8/06 ,  C22C38/02 ,  C22C38/04 ,  C22C38/22 ,  C22C38/28 ,  C22C38/32 ,  C22C38/26 ,  C22C38/60 ,  C22C38/44 ,  C22C38/24 ,  C22C38/54 ,  C22C38/50 ,  C22C38/06 ,  C22C38/20

摘要： Disclosed are a case hardened steel which is suitable as a material for producing mechanical structural parts having high rotating bending fatigue strength and impact fatigue strength at a relatively low cost, and a method of producing the same. The case hardening steel has a chemical composition containing, by mass %, C, Si, Mn, P, S, Cr, Mo, B, Ti, N, and O within a range satisfying a predetermined relationship, and Al in at least a predetermined amount in relation to the B, N, and Ti contents, with the balance being Fe and inevitable impurities, wherein √I≤80 is satisfied, where I represents an area in μm2 of an oxide-based inclusion located at the center of a fish-eye on a fracture surface of the case hardening steel after being subjected to carburizing-quenching and tempering and subsequently to a rotating bending fatigue test.

公开(公告)号：US10443110B2

公开(公告)日：2019-10-15

申请号：US15126838

申请日：2014-09-09

申请人： JFE STEEL CORPORATION

发明人： Shigeki Kitsuya ,  Katsuyuki Ichimiya ,  Kazukuni Hase ,  Teruhisa Kinugawa ,  Naoki Matsunaga ,  Kenji Hayashi ,  Masayuki Horie ,  Yusuke Terazawa ,  Shigeru Endo

IPC分类号： C21D9/46 ,  C22C38/54 ,  C22C38/50 ,  C22C38/48 ,  C22C38/46 ,  C22C38/44 ,  C22C38/42 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/00 ,  C21D8/02 ,  C21D1/18 ,  B22D11/00 ,  B21J5/02 ,  C22C38/58 ,  C22C38/08 ,  C22C38/12 ,  C22C38/14 ,  C22C38/16 ,  C22C38/18 ,  C22C38/32 ,  C21D7/13 ,  C21D8/00 ,  C21D9/00

摘要： A high toughness and high tensile strength thick steel plate has a plate thickness of 100 mm or more, wherein a reduction of area in a center of the plate thickness by tension in a plate thickness direction is 40% or more. Thus, a high tensile strength thick steel plate with excellent strength and toughness in a center of the plate thickness can be obtained with no need for a larger production line, even in the case of producing a high strength thick steel plate for which the addition amount of alloying element needs to be increased.

公开(公告)号：US10358688B2

公开(公告)日：2019-07-23

申请号：US15304702

申请日：2015-04-24

申请人： JFE Steel Corporation

发明人： Shigeki Kitsuya ,  Katsuyuki Ichimiya ,  Kazukuni Hase ,  Shigeru Endo

IPC分类号： C21D9/46 ,  C21D8/02 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/08 ,  C22C38/14 ,  C22C38/16 ,  C22C38/42 ,  C22C38/44 ,  C22C38/50 ,  C22C38/54 ,  C22C38/58 ,  B21B1/22 ,  B21B1/26 ,  C22C38/00 ,  C22C38/46 ,  C22C38/48 ,  B21B3/00

摘要： A steel plate has excellent strength and toughness in a mid-thickness part thereof, despite having a plate thickness of 100 mm or greater. The steel plate has a chemical composition containing specific amounts of C, Si, Mn, P, S, Cr, Ni, Al, N, B, and O, with the balance being Fe and incidental impurities, and having an equivalent carbon content CeqIIW of 0.65 or greater. The steel plate has a yield strength of 620 MPa or greater, a plate thickness of 100 mm or greater, and has a microstructure in which prior γ grain size in a mid-thickness part of the steel plate has a maximum value, expressed as an equivalent circle diameter, of 150 μm or less, and a total area ratio of martensite and bainite in the mid-thickness part is 80% or greater.