公开(公告)号：US20190330721A1

公开(公告)日：2019-10-31

申请号：US16312214

申请日：2016-09-21

申请人： NIPPON STEEL & SUMITOMO METAL CORPORATION

发明人： Kunio HAYASHI ,  Masafumi AZUMA

IPC分类号： C22C38/02 ,  C22C38/44 ,  C22C38/42 ,  C22C38/14 ,  C22C38/12 ,  C21D9/46 ,  C22C38/46 ,  C22C38/54 ,  C22C38/58

摘要： A steel sheet includes a predetermined chemical composition, and includes a steel structure represented by, in a volume fraction, tempered martensite and bainite: 70% or more and less than 92% in total, retained austenite: 8% or more and less than 30%, ferrite: less than 10%, fresh martensite: less than 10%, and pearlite: less than 10%. A number density of iron-base carbides in tempered martensite and lower bainite is 1.0×106 (pieces/mm2) or more, and an effective crystal grain diameter of tempered martensite and bainite is 5 μm or less.

公开(公告)号：US20180202019A1

公开(公告)日：2018-07-19

申请号：US15743432

申请日：2015-07-13

申请人： NIPPON STEEL & SUMITOMO METAL CORPORATION

发明人： Yuri TODA ,  Masafumi AZUMA ,  Akihiro UENISHI ,  Hiroyuki KAWATA ,  Naoki MARUYAMA ,  Genichi SHIGESATO

IPC分类号： C21D9/46 ,  C21D8/02 ,  C23C2/06 ,  C23C2/40 ,  C23F17/00 ,  C22C38/38 ,  C22C38/16 ,  C22C38/14 ,  C22C38/12 ,  C22C38/08 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/00

摘要： A steel sheet according to an aspect of the present invention has predetermined chemical composition, in which a structure at a thickness ¼ portion includes, in terms of volume ratios, tempered martensite: 70% or more and one or both of ferrite and bainite: a total of less than 20%, in the structure at the thickness ¼ portion, a volume ratio of residual austenite is less than 10%, a volume ratio of fresh martensite is 10% or less, a volume ratio of pearlite is 10% or less, and a total volume ratio of the residual austenite, the fresh martensite, and the pearlite is 15% or less, a number density of iron-based carbides having a major axis of 5 nm or more in the tempered martensite at the thickness ¼ portion is 5×107 particles/mm2 or more, a ratio of the number of ε-type carbides in the number of the iron-based carbides having the major axis of 5 nm or more at the thickness ¼ portion is 20% or more, and a tensile strength is 780 MPa or higher.

公开(公告)号：US20180171429A1

公开(公告)日：2018-06-21

申请号：US15563989

申请日：2016-04-07

申请人： NIPPON STEEL & SUMITOMO METAL CORPORATION

发明人： Yoshihiro SUWA ,  Shinichiro TABATA ,  Masafumi AZUMA ,  Kazuo HIKIDA

IPC分类号： C21D9/46 ,  C21D8/02 ,  C21D6/00 ,  C21D1/18 ,  C22C38/58 ,  C22C38/54 ,  C22C38/50 ,  C22C38/48 ,  C22C38/44 ,  C22C38/42 ,  C22C38/34 ,  C22C38/24 ,  C22C38/06 ,  C22C38/00

CPC分类号： C21D9/46 ,  C21D1/18 ,  C21D1/19 ,  C21D1/22 ,  C21D6/004 ,  C21D6/005 ,  C21D6/008 ,  C21D8/0205 ,  C21D8/0263 ,  C21D2211/001 ,  C21D2211/008 ,  C22C38/001 ,  C22C38/002 ,  C22C38/005 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/14 ,  C22C38/20 ,  C22C38/22 ,  C22C38/24 ,  C22C38/26 ,  C22C38/28 ,  C22C38/32 ,  C22C38/34 ,  C22C38/42 ,  C22C38/44 ,  C22C38/48 ,  C22C38/50 ,  C22C38/54 ,  C22C38/58

摘要： A heat-treated steel sheet member having a chemical including, by mass %: C: 0.05 to 0.50%; Si: 0.50 to 5.0%; Mn: 1.5 to 4.0%; P: 0.05% or less; S: 0.05% or less; N: 0.01% or less; Ti: 0.01 to 0.10%; B: 0.0005 to 0.010%; Cr: optional amounts of Ni, Cu, Mo, V, Ca, Al, Nb, and REM, with the balance: Fe and impurities. The steel sheet member has a microstructure comprising: mainly martensite; and retained austenite of which a volume ratio is 5.0% or higher, a number density of retained carbide in the steel sheet member having circle-equivalent diameters of 0.1 mm or larger is 4.0×103/mm2 or lower, [(log fg0−log fg(0.02))/0.02

公开(公告)号：US20170369979A1

公开(公告)日：2017-12-28

申请号：US15696650

申请日：2017-09-06

申请人： NIPPON STEEL & SUMITOMO METAL CORPORATION

发明人： Chisato WAKABAYASHI ,  Masafumi AZUMA ,  Nobuhiro FUJITA ,  Kohichi SANO

IPC分类号： C23C2/06 ,  C23C2/02 ,  B32B15/01 ,  C21D8/04 ,  C22C38/38 ,  C22C38/34 ,  C22C38/14 ,  C22C38/12 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/00 ,  C22C18/04 ,  C22C18/00 ,  C21D9/48 ,  C23C2/28 ,  C21D8/02

CPC分类号： C23C2/06 ,  B32B15/013 ,  C21D8/0263 ,  C21D8/0426 ,  C21D8/0436 ,  C21D8/0473 ,  C21D8/0478 ,  C21D9/48 ,  C21D2211/002 ,  C21D2211/005 ,  C21D2211/008 ,  C21D2211/009 ,  C22C18/00 ,  C22C18/04 ,  C22C38/001 ,  C22C38/002 ,  C22C38/005 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/12 ,  C22C38/14 ,  C22C38/34 ,  C22C38/38 ,  C23C2/02 ,  C23C2/28 ,  Y10T428/12799

摘要： Provided is a high-strength hot-dip galvanized steel sheet having excellent plating adhesion, formability, and hole expandability with an ultimate tensile strength of 980 MPa or more, the hot-dip galvanized steel sheet comprising a hot-dip galvanized layer formed on a surface of a base steel sheet. The base steel sheet contains, by mass %, C: 0.05% to 0.4%; Si: 0.01% to 3.0%; Mn: 0.1% to 3.0%; Al: 0.01 to 2.0%; in which Si+Al>0.5%, P: limited to 0.04% or less; S: limited to 0.05% or less; N: limited to 0.01% or less; and a balance including Fe and inevitable impurities, a microstructure of the base steel sheet contains 40% or more by total volume fraction of martensite and bainite, 8% or more by volume fraction of residual austenite, and a balance of the microstructure being ferrite or ferrite and 10% or less by volume fraction of pearlite. The martensite contains 10% or more by total volume fraction of two or more kinds of three kinds of martensites (1), (2), and (3), and the hot-dip galvanized layer contains less than 7 mass % of Fe.

公开(公告)号：US20150376730A1

公开(公告)日：2015-12-31

申请号：US14767807

申请日：2014-05-16

申请人： NIPPON STEEL & SUMITOMO METAL CORPORATION

发明人： Hiroshi SHUTO ,  Masafumi AZUMA ,  Akifumi SAKAKIBARA ,  Yuuki KANZAWA ,  Ken KIMURA

IPC分类号： C21D8/02 ,  C21D9/46 ,  C22C38/38 ,  C22C38/28 ,  C22C38/26 ,  C22C38/16 ,  C22C38/14 ,  C22C38/12 ,  C22C38/08 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/00 ,  C23C2/02 ,  C23C2/06 ,  B32B15/01 ,  C21D6/00

CPC分类号： C21D8/0226 ,  B32B15/012 ,  B32B15/013 ,  B32B15/043 ,  B32B15/18 ,  C21D1/20 ,  C21D6/001 ,  C21D6/002 ,  C21D6/005 ,  C21D6/008 ,  C21D8/0263 ,  C21D8/0426 ,  C21D8/0473 ,  C21D9/46 ,  C21D2211/002 ,  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 ,  C22C38/26 ,  C22C38/28 ,  C22C38/38 ,  C23C2/02 ,  C23C2/06 ,  C23C30/00 ,  C23C30/005 ,  Y10T428/12799 ,  Y10T428/12951 ,  Y10T428/12972

摘要： A hot-rolled steel sheet has a composition containing: in mass %, C: 0.01 to 0.2%; Si: 2.5% or less; Mn: 4.0% or less; P: 0.10% or less; S: 0.03% or less; Al: 0.001 to 2.0%; N: 0.01% or less; and O: 0.01% or less, and one kind or a total of two kinds of Ti and Nb for 0.01 to 0.30%. An average effective crystal grain diameter at a sheet thickness ¼ part is 10 μm or less, and an average effective crystal grain diameter at a part of a range of 50 μm from a surface is 6 μm or less. A structure of the steel sheet is tempered martensite or lower bainite, and a volume fraction thereof is 90% or more as a total.

摘要翻译： 热轧钢板的组成为：质量％，C：0.01〜0.2％， Si：2.5％以下; Mn：4.0％以下; P：0.10％以下; S：0.03％以下; Al：0.001〜2.0％ N：0.01％以下 和O：0.01％以下，0.01〜0.30％的Ti和Nb中的一种或两种。 平均有效晶粒直径为10μm以下，平均有效晶粒直径为10μm以下，从表面的50μm的一部分的平均有效晶粒直径为6μm以下。 钢板的结构是回火马氏体或下贝氏体，其体积分数总计为90％以上。

公开(公告)号：US20190169729A1

公开(公告)日：2019-06-06

申请号：US16092947

申请日：2016-07-15

申请人： NIPPON STEEL & SUMITOMO METAL CORPORATION

发明人： Takafumi YOKOYAMA ,  Kunio HAYASHI ,  Masafumi AZUMA ,  Eisaku SAKURADA ,  Hiroyuki KAWATA ,  Genki ABUKAWA

IPC分类号： C23C2/06 ,  C23C2/02 ,  C22C38/54 ,  C22C38/58 ,  C22C38/06 ,  C22C38/00 ,  C22C38/50 ,  C22C38/48 ,  C22C38/46 ,  C22C38/44 ,  C22C38/42 ,  C21D9/46

摘要： A hot-dip galvanized steel sheet includes: a predetermined chemical composition; and a steel structure represented by: in terms of area ratio, polygonal ferrite: 10% or less; upper bainite: 20% or less; retained austenite: 5% or less; and martensite: 70% or more, in which: martensite having Fe carbides at a number density of 1×106/mm2 or more is contained by 50% or more, in terms of area ratio, with respect to the entire amount of martensite; and the steel structure has an average effective crystal grain diameter of 5.0 μm or less.

公开(公告)号：US20150329950A1

公开(公告)日：2015-11-19

申请号：US14653787

申请日：2014-02-25

申请人： NIPPON STEEL & SUMITOMO METAL CORPORATION

发明人： Masafumi AZUMA ,  Hiroshi SHUTO ,  Tatsuo YOKOI ,  Yuuki KANZAWA ,  Akihiro UENISHI

IPC分类号： C23C2/02 ,  C21D9/46 ,  C23C2/06 ,  C22C38/38 ,  C22C38/28 ,  C22C38/26 ,  C22C38/16 ,  C22C38/14 ,  C22C38/12 ,  C22C38/08 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/00 ,  C21D8/02

CPC分类号： C23C2/02 ,  C21D8/021 ,  C21D8/0226 ,  C21D8/0263 ,  C21D9/46 ,  C21D2211/002 ,  C21D2211/008 ,  C22C38/00 ,  C22C38/001 ,  C22C38/002 ,  C22C38/005 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/08 ,  C22C38/12 ,  C22C38/14 ,  C22C38/16 ,  C22C38/18 ,  C22C38/26 ,  C22C38/28 ,  C22C38/38 ,  C23C2/06

摘要： Provided is a high-strength hot-rolled steel sheet consisting of, in mass %, C: 0.01% to 0.2%, Si: 0% to 2.5%, Mn: 0% to 4.0%, Al: 0% to 2.0%, N: 0% to 0.01%, Cu: 0% to 2.0%, Ni: 0% to 2.0%, Mo: 0% to 1.0%, V: 0% to 0.3%, Cr: 0% to 2.0%, Mg: 0% to 0.01%, Ca: 0% to 0.01%, REM: 0% to 0.1%, B: 0% to 0.01%, P: less than or equal to 0.10%, S: less than or equal to 0.03%, O: less than or equal to 0.01%, one or both of Ti and Nb: 0.01% to 0.30% in total, and the balance being Fe and inevitable impurities. The steel sheet has a structure in which a total volume fraction of tempered martensite or lower bainite is 90% or more, a dislocation density thereof is greater than or equal to 5×1013 (1/m2) and less than or equal to 1×1016 (1/m2) and 1×106 (numbers/mm2) or more iron-based carbides are included therein.

摘要翻译： 本发明提供以质量％计含有C：0.01〜0.2％，Si：0〜2.5％，Mn：0〜4.0％，Al：0〜2.0％的高强度热轧钢板， N：0〜0.01％，Cu：0〜2.0％，Ni：0〜2.0％，Mo：0〜1.0％，V：0〜0.3％，Cr：0〜2.0％ 0％〜0.01％，Ca：0％〜0.01％，REM：0％〜0.1％，B：0％〜0.01％，P：小于等于0.10％，S：小于等于0.03％ O：小于或等于0.01％，Ti和Nb中的一种或两种：总计为0.01％至0.30％，余量为Fe和不可避免的杂质。 钢板的回火马氏体或下贝氏体的总体积分率为90％以上，位错密度大于或等于5×1013（1 / m2）且小于或等于1× 1016（1 / m2）和1×106（数/ mm2）以上的铁基碳化物。

公开(公告)号：US20150001188A1

公开(公告)日：2015-01-01

申请号：US14490538

申请日：2014-09-18

申请人： NIPPON STEEL & SUMITOMO METAL CORPORATION

发明人： Hatsuhiko OIKAWA ,  Hideki HAMATANI ,  Masafumi AZUMA ,  Noriyuki SUZUKI ,  Fuminori WATANABE ,  Naoki MARUYAMA ,  Hiroyuki KAWATA

IPC分类号： B23K11/16 ,  B23K11/11

CPC分类号： B23K11/115 ,  B23K11/16 ,  B23K11/166 ,  B23K2101/18 ,  B23K2101/34 ,  B23K2103/04 ,  B32B15/011 ,  C22C38/001 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  Y10T428/12347 ,  Y10T428/12965

摘要： Provided is a spot welded joint (10) which includes at least one thin steel plate with a tensile strength of 750 MPa to 1850 MPa and a carbon equivalent Ceq of equal to or more than 0.22 mass % to 0.55 mass % and in which a nugget (3) is formed in an interface of the thin steel plates (1A, 1B). In a nugget outer layer zone, a microstructure consists of a dendrite structure in which an average value of arm intervals is equal to or less than 12 μm, an average grain diameter of carbides contained in the microstructure is 5 nm to 100 nm, and a number density of carbides is equal to or more than 2×106/mm2.

摘要翻译： 提供了一种点焊接头（10），其包括至少一个拉伸强度为750MPa至1850MPa的薄钢板和等于或大于0.22质量％至0.55质量％的碳当量Ceq，并且其中熔核 （3）形成在薄钢板（1A，1B）的界面中。 在熔核外层区域中，微观组织由臂间隔的平均值等于或小于12μm的枝晶结构构成，微观结构中所含的碳化物的平均粒径为5nm〜100nm， 碳化物的数密度等于或大于2×10 6 / mm 2。

公开(公告)号：US20190211427A1

公开(公告)日：2019-07-11

申请号：US16334286

申请日：2016-09-21

申请人： NIPPON STEEL & SUMITOMO METAL CORPORATION

发明人： Kohichi SANO ,  Masafumi AZUMA ,  Mutsumi SAKAKIBARA ,  Akihiro UENISHI ,  Koutarou HAYASHI

IPC分类号： C22C38/04 ,  C22C38/06 ,  C22C38/02 ,  C22C38/00 ,  C22C38/60 ,  C22C38/20 ,  C22C38/22 ,  C22C38/12 ,  C22C38/08 ,  C22C38/14 ,  C22C38/38 ,  C23C2/02 ,  C23C2/06 ,  C23C2/40

CPC分类号： C22C38/04 ,  C21D8/0205 ,  C21D8/0226 ,  C21D8/0236 ,  C21D8/0263 ,  C21D9/46 ,  C21D2211/001 ,  C22C38/00 ,  C22C38/001 ,  C22C38/002 ,  C22C38/005 ,  C22C38/008 ,  C22C38/02 ,  C22C38/06 ,  C22C38/08 ,  C22C38/12 ,  C22C38/14 ,  C22C38/20 ,  C22C38/22 ,  C22C38/38 ,  C22C38/58 ,  C22C38/60 ,  C23C2/02 ,  C23C2/06 ,  C23C2/40

摘要： A steel sheet according to an aspect of the present invention includes a predetermined chemical composition; in which a metallographic structure in a ¼ t portion contains residual austenite of 4 volume % to 70 volume %; [Mn]γ/[Mn]ave>1.5 is satisfied in the ¼ t portion; fγs/fγ≤0.30 and [C]×[Mn]≥0.15 are satisfied in the ¼ t portion.

公开(公告)号：US20180237881A1

公开(公告)日：2018-08-23

申请号：US15753599

申请日：2015-08-21

申请人： NIPPON STEEL & SUMITOMO METAL CORPORATION

发明人： Riki OKAMOTO ,  Hiroyuki KAWATA ,  Masafumi AZUMA ,  Akihiro UENISHI ,  Naoki MARUYAMA

IPC分类号： C21D9/46 ,  C22C38/32 ,  C22C38/28 ,  C22C38/16 ,  C22C38/14 ,  C22C38/12 ,  C22C38/08 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/00 ,  C21D8/02 ,  C23C2/02 ,  C23C2/40 ,  C23F17/00 ,  C25D5/36

CPC分类号： C21D9/46 ,  C21D8/0226 ,  C21D8/0236 ,  C21D8/0263 ,  C21D8/0278 ,  C21D2211/002 ,  C21D2211/005 ,  C21D2211/008 ,  C22C38/00 ,  C22C38/001 ,  C22C38/002 ,  C22C38/005 ,  C22C38/008 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/08 ,  C22C38/12 ,  C22C38/14 ,  C22C38/16 ,  C22C38/28 ,  C22C38/32 ,  C22C38/58 ,  C23C2/02 ,  C23C2/40 ,  C23F17/00 ,  C25D5/36

摘要： A steel sheet includes: a predetermined chemical composition; and a steel structure containing, in are a fraction, 2% or more of ferrite and bainite, in which an average dislocation density in the ferrite and an average dislocation density in the bainite are both h3×1012 m/m3 to 1×1014 m/m3, and an average grain diameter of the ferrite and the bainite is 5 μm or less.