公开(公告)号：US10385436B2

公开(公告)日：2019-08-20

申请号：US15033087

申请日：2014-10-30

Applicant: Daiwa Steel Tube Industries Co., Ltd.

Inventor： Shinichiro Nakamura ,  Mutsumu Tanimoto ,  Atsushi Yamada

IPC: C23C2/36 ,  C23C2/00 ,  C23C2/40 ,  B21C37/09 ,  C23C2/02 ,  C23C2/38 ,  C23C2/06 ,  C23C26/02 ,  F16L9/02 ,  C23C2/18 ,  C23C2/28 ,  F23D14/20 ,  F27B3/20

Abstract: [Problem] To provide: a molten metal plating furnace that can increase plating quality and work efficiency; a system for producing and method for producing a metal plated product; and a metal plated steel tube obtained by means of the method for producing. [Solution] The system for producing has at least one plating implementation unit that performs molten metal plating of a plating processing subject, and at least one plating implementation unit has a plating bath and a heating device for heating the plating bath, wherein in the heating device, an array of fuel filling openings and an array of air filling openings are formed that are facing in a manner so as to discharge air and fuel to a combustion region in common along a combustion chamber, the effective opening cross-sectional size of at least the majority of the openings of at least one of the opening arrays can be adjusted by means of an adjustment mechanism for adjusting the extent of a medium filling opening array, and when the size of both opening arrays can be adjusted, individual adjustment of the arrays is possible.

公开(公告)号：US10351942B2

公开(公告)日：2019-07-16

申请号：US14390802

申请日：2012-09-11

Applicant: Takafumi Yokoyama ,  Shigeki Nomura

Inventor： Takafumi Yokoyama ,  Shigeki Nomura

IPC: C21D8/02 ,  C21D8/04 ,  C21D9/46 ,  C22C38/00 ,  C22C38/08 ,  C22C38/16 ,  C22C38/18 ,  C22C38/28 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/12 ,  C23C2/00 ,  C23C2/06 ,  C23C2/28 ,  C22C38/14 ,  C23C2/02 ,  C23C2/40 ,  B32B15/01 ,  C22C18/04 ,  C21D9/48 ,  C21D1/20

Abstract: In a high strength hot-dip galvannealed hot-rolled steel sheet that has an excellent hole expansibility suitable for a stretch flanging and preferably has a high yield ratio and a tensile strength of at least 650 MPa, a hot-rolled steel sheet used as a base material for plating has a chemical composition comprising: in mass %, C: from at least 0.01 and at most 0.20%; Si: at most 0.50%; Mn: from at least 0.01% to at most 1.30%; P: at most 0.05%; S: at most 0.01%; N: at most 0.01%; Al: at most 0.50%; and Ti: from at least 0.05% to at most 0.50%, and a steel structure consisting of a polygonal ferrite having at least 80 area % and the remainder containing one kind or two or more kinds selected from bainitic ferrite, bainite, pearlite, and cementite.

公开(公告)号：US10301693B2

公开(公告)日：2019-05-28

申请号：US15143965

申请日：2016-05-02

Applicant: JFE Steel Corporation

Inventor： Katsumi Nakajima ,  Kazuhiko Yamazaki ,  Chikara Kami

IPC: C21D1/20 ,  C21D6/00 ,  C21D9/46 ,  C22C18/04 ,  C22C38/00 ,  C22C38/14 ,  B32B15/01 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/08 ,  C22C38/12 ,  C21D8/02 ,  C21D8/04 ,  C23C2/02 ,  C23C2/40 ,  B21D22/02 ,  C21D1/84 ,  C23C2/06 ,  C23C2/28 ,  C23F17/00 ,  C22C38/16 ,  C22C38/18 ,  C22C38/24 ,  C22C38/28 ,  C22C38/32 ,  C22C38/38 ,  C22C38/44 ,  C22C38/46 ,  C22C38/50 ,  C22C38/58 ,  C22C38/42 ,  C22C38/48 ,  C22C38/54

Abstract: A steel slab having a composition containing C: more than 0.07% and 0.2% or less, Si: 2.0% or less, Mn: 1.0% to 3.0%, Al: 0.1% or less, Ti: 0.05% to 0.3%, and V: 0.05% to 0.3% on a mass percent basis is heated to 1100° C. or more and is subjected to rough rolling and finish rolling. In the finish rolling, the total rolling reduction of two final passes is 30% or more, and the finish rolling temperature ranges from (Ar3 transformation temperature) to (Ar3 transformation temperature+120° C.). Cooling is started within 2 seconds after the finish rolling. Coiling is performed at an average cooling rate of 40° C./s or more at a coiling temperature in the range of 300° C. to 500° C. The resulting high-strength hot-rolled steel sheet has a microstructure in which a bainite phase constitutes more than 90% by volume, the average lath interval of bainite is 0.45 μm or less, and the ratio of Fe-based carbide precipitated in bainite lath to all Fe-based carbide is 10% or more, has a high tensile strength of 900 MPa or more, and has significantly improved punchability in mass production.

公开(公告)号：US10287649B2

公开(公告)日：2019-05-14

申请号：US15127987

申请日：2015-03-18

Applicant: ThyssenKrupp Steel Europe AG ,  ThyssenKrupp AG

Inventor： Andreas Bongards ,  Sigrun Voβ ,  Roland Sebald

IPC: C21D9/46 ,  C21D8/02 ,  C23C2/06 ,  C22C38/02 ,  C23C2/02 ,  C23C2/28 ,  B32B15/01 ,  C22C38/00 ,  C22C38/06 ,  C22C38/42 ,  C22C38/44 ,  C22C38/46 ,  C22C38/48 ,  C22C38/50 ,  C22C38/54 ,  C22C38/58

Abstract: A cold-rolled flat steel product may have a yield strength Rp0.2 of not more than 320 MPa, a fracture elongation A80 of at least 20% and a microstructure having by percent area 62%-82% ferrite, 10%-30% martensite, 1.5%-8% residual austenite, and a sum total of not more than 10% other microstructure constituents. The flat steel product may comprise a steel alloy containing in percent by weight 0.06%-0.1% C; 0.15%-0.4% Si; 1.5%-2% Mn; 0.2%-0.5% Cr; not more than 0.1% Al; wherein the sum total of C, Si, Mn, and Cr is at least 2.3% and not more than 2.8%; wherein the sum total of Si and Al is not more than 0.4%; not more than 0.03% P; not more than 0.006% S; not more than 0.008% N; unavoidable impurities including not more than 0.0006% B, not more than 0.02% V, and not more than 0.01% each of Nb and Ti, and not more than 0.1% each of Mo, Ni, and Cu; as well as iron. For production of such a flat steel product, a cold-rolled flat steel product may first be produced and then brought to 760-860° C. in a continuous run and kept at that temperature over an annealing period Gt for which, depending on the thickness D of the flat steel product, Gtu≤Gt≤Gto with Gtu [s]=3.56*D2 [s/mm2]−5.1*D [s/mm]+9.8 s Gto [s]=−21.4*D2 [s/mm2]+132.8*D [s/mm]+47 s.

公开(公告)号：US20190119776A1

公开(公告)日：2019-04-25

申请号：US16094849

申请日：2017-04-18

Applicant: ArcelorMittal

Inventor： Jonas STAUDTE ,  Hubert SAINT-RAYMOND ,  Michel Roger Louis BORDIGNON ,  Thierry HOURMAN ,  Pauline BRIAULT

IPC: C21D9/56 ,  C21D9/46 ,  C21D9/573 ,  C23C2/02 ,  C23C2/06 ,  C23C2/40 ,  C23F17/00

Abstract: A method for producing a metallic coated steel sheet is provided. The method includes continuously annealing a steel sheet in a continuous annealing furnace and hot dip coating the steel sheet.

公开(公告)号：US10266906B2

公开(公告)日：2019-04-23

申请号：US14779772

申请日：2014-03-26

Applicant: JFE STEEL CORPORATION

Inventor： Hidetaka Kawabe ,  Takeshi Yokota

IPC: C21D8/02 ,  C23C2/06 ,  C23C2/40 ,  C21D9/46 ,  C22C38/00 ,  C22C38/06 ,  B32B15/01 ,  C22C38/02 ,  C22C38/04 ,  C23C2/02 ,  C23C2/28 ,  C21D6/00 ,  C23F17/00

Abstract: A high-strength galvanized steel sheet has a chemical composition containing, by mass %, C: 0.16% or more and 0.24% or less, Si: 0.8% or more and 1.8% or less, Mn: 1.0% or more and 3.0% or less, P: 0.020% or less, S: 0.0040% or less, Al: 0.01% or more and 0.1% or less, N: 0.01% or less, Ca: 0.0001% or more and 0.0020% or less, and the balance including Fe and incidental impurities, and a microstructure, in which the total area ratio of a ferrite phase and a bainite phase with respect to the whole microstructure is 30% or more and 70% or less, in which the area ratio of a tempered martensite phase with respect to the whole microstructure is 20% or more and 40% or less, in which the area ratio of a retained austenite phase with respect to the whole microstructure is 10% or more and 20% or less, and in which the area ratio of a martensite phase with respect to the whole microstructure is 2% or more and 20% or less.

公开(公告)号：US20190078187A1

公开(公告)日：2019-03-14

申请号：US16083634

申请日：2017-01-09

Applicant: Fontaine Holdings NV

Inventor： Thomas PINGER ,  Lars BAUMGÜRTEL

IPC: C23C2/00 ,  C23C2/26 ,  C23C2/14 ,  C23C2/06 ,  C23C2/02

Abstract: The invention relates to a system and a method for the hot-dip galvanization of motor-vehicle components, preferably for mass-production hot-dip galvanization of a plurality of identical or similar motor-vehicle components, in particular in batches, preferably for batch galvanization, especially preferably for high-precision hot-dip galvanization.

公开(公告)号：US10227672B2

公开(公告)日：2019-03-12

申请号：US15106606

申请日：2014-12-01

Applicant: JFE STEEL CORPORATION

Inventor： Hiroshi Hasegawa ,  Shinjiro Kaneko ,  Yoichi Makimizu ,  Yoshitsugu Suzuki

IPC: C22C38/38 ,  C22C38/26 ,  C22C38/28 ,  C21D9/46 ,  C21D8/02 ,  C23C2/06 ,  C23C2/02 ,  C23C2/28 ,  C22C38/00 ,  C22C38/58 ,  B32B15/01 ,  C22C38/02 ,  C22C38/06 ,  C22C38/20 ,  C22C38/22 ,  C22C38/24 ,  C22C38/32 ,  C22C38/48 ,  C22C38/50 ,  C22C38/54 ,  C21D1/22 ,  C21D6/00

Abstract: A high-strength hot-dip galvanized steel sheet having a surface coated with a hot-dip galvanized coating, the steel sheet having a chemical composition comprising C: more than 0.10% and less than 0.18%, Si: 0.01 to 1.00%, Mn: 1.5 to 4.0%, P: 0.100% or less, S: 0.020% or less, Al: 0.010 to 0.500%, Cr: 0.010 to 2.000%, Nb: 0.005 to 0.100%, Ti: 0.005 to 0.100%, B: more than 0.0005% and 0.0030% or less, and Fe and incidental impurities, and a method for producing the same. The steel sheet has a microstructure including ferrite having an area fraction in the range of 0 to 10%, martensite having an area fraction in the range of 15 to 60%, tempered martensite having an area fraction in the range of 20 to 50%, and bainitic ferrite having an area fraction in the range of 20 to 50%.

公开(公告)号：US20190062863A1

公开(公告)日：2019-02-28

申请号：US16075747

申请日：2017-01-12

Applicant: JFE STEEL CORPORATION

Inventor： Yuji TANAKA ,  Sarka MIKMEKOVA ,  Takako YAMASHITA ,  Yoshie OBATA

IPC: C21D9/46 ,  C21D8/02 ,  C21D6/00 ,  C23C2/02 ,  C23C2/40 ,  C23C2/06 ,  B32B15/01 ,  C22C38/04 ,  C22C38/06 ,  C22C38/02 ,  C22C38/00

Abstract: A high-strength cold rolled steel sheet has both high strength, i.e. a tensile strength of 900 MPa or more, and high workability, i.e. a total elongation of 20% or more, and also has a low yield ratio of less than 60%. The high-strength cold rolled steel sheet comprises: a predetermined chemical composition; and a steel structure having, in area ratio, ferrite: 30% to 75%, martensite: 15% to 40%, and retained austenite: 10% to 30%. In the case where a distribution of crystal grain circularity of the retained austenite is represented by a histogram with a class range of more than 0.1×(n−1) and 0.1×n or less and a class value of 0.1×n (n is an integer from 1 to 10), a mode of the crystal grain circularity of the retained austenite is 0.7 or more.

公开(公告)号：US20190032187A1

公开(公告)日：2019-01-31

申请号：US16072668

申请日：2017-01-26

Applicant: JFE Steel Corporation

Inventor： HIROMI YOSHITOMI ,  Hiroyuki Masuoka ,  Seisuke Tsuda ,  Yasuhiro Nishimura ,  Masaki Koba

IPC: C23C2/06 ,  C22C38/02 ,  C22C38/06 ,  C22C38/00 ,  C22C38/60 ,  C22C38/16 ,  C22C38/14 ,  C22C38/12 ,  C22C38/38 ,  C22C38/22 ,  C22C38/32 ,  C22C38/26 ,  C22C38/28 ,  C22C38/08 ,  C23C2/40 ,  C23C2/28 ,  C23C2/02 ,  C21D8/02

Abstract: Provided are a high-yield-ratio high-strength galvanized steel sheet and a method for manufacturing thereof. The high-yield-ratio high-strength galvanized steel sheet has a steel sheet having a specified chemical composition and a metallographic structure including, in terms of area ratio, in terms of area ratio, 15% or less of ferrite, 20% or more and 50% or less of martensite, and bainite and tempered martensite in a total amount of 30% or more, and a galvanized layer formed on the steel sheet having a coating weight of 20 g/m2 to 120 g/m2 per side, in which a yield strength ratio is 65% or more, a tensile strength is 950 MPa or more, and Mn oxides are contained in the galvanized layer in an amount of 0.015 g/m2 to 0.050 g/m2.