公开(公告)号：US20180002800A1

公开(公告)日：2018-01-04

申请号：US15543062

申请日：2015-11-24

Applicant: JFE STEEL CORPORATION

Inventor： Hiroshi HASEGAWA ,  Hideyuki KIMURA ,  Yoshimasa FUNAKAWA ,  Yoichi MAKIMIZU ,  Yoshitsugu SUZUKI

IPC: C23C2/40 ,  C22C38/04 ,  C21D9/46 ,  C22C38/02 ,  C23C2/28 ,  C22C38/06

CPC classification number: C23C2/40 ,  B32B15/013 ,  B32B15/04 ,  B32B15/043 ,  B32B15/18 ,  C21D6/001 ,  C21D6/002 ,  C21D6/005 ,  C21D6/008 ,  C21D8/0205 ,  C21D8/0226 ,  C21D8/0236 ,  C21D8/0263 ,  C21D8/0273 ,  C21D9/46 ,  C21D2211/001 ,  C21D2211/005 ,  C21D2211/008 ,  C22C38/00 ,  C22C38/001 ,  C22C38/002 ,  C22C38/005 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/08 ,  C22C38/12 ,  C22C38/14 ,  C22C38/16 ,  C22C38/24 ,  C22C38/26 ,  C22C38/38 ,  C22C38/58 ,  C23C2/02 ,  C23C2/06 ,  C23C2/12 ,  C23C2/28 ,  C23C2/285 ,  C23C30/00 ,  C23C30/005 ,  Y10T428/12757 ,  Y10T428/12799 ,  Y10T428/12951 ,  Y10T428/12958 ,  Y10T428/12972

Abstract: A high-strength galvanized steel sheet that includes a chemical composition containing, by mass %, C: 0.15% or more and 0.25% or less, Si: 0.50% or more and 2.5% or less, Mn: 2.3% or more and 4.0% or less, P: 0.100% or less, S: 0.02% or less, Al: 0.01% or more and 2.5% or less, and Fe and inevitable impurities. The steel sheet having a microstructure containing, by an area percentage basis, a tempered martensite phase: 30% or more and 73% or less, a ferrite phase: 25% or more and 68% or less, a retained austenite phase: 2% or more and 20% or less, and other phases: 10% or less (including 0%), the other phases containing a martensite phase: 3% or less (including 0%) and a bainitic ferrite phase: less than 5% (including 0%).

公开(公告)号：US20170130296A1

公开(公告)日：2017-05-11

申请号：US15318673

申请日：2015-06-05

Applicant: JFE STEEL CORPORATION

Inventor： Gentaro TAKEDA ,  Masaru MIYAKE ,  Yoichi MAKIMIZU ,  Yoshitsugu SUZUKI ,  Yoshikazu SUZUKI

IPC: C21D9/56 ,  C23C2/40 ,  C23C2/06 ,  C23C2/28 ,  C23C2/02

Abstract: A method of producing a galvannealed steel sheet includes: annealing a steel strip by conveying the steel strip through a heating zone including a direct fired furnace, a soaking zone, and a cooling zone in this order in an annealing furnace; hot-dip galvanizing the steel strip discharged from the cooling zone; and heat-alloying a galvanized coating formed on the steel strip. Mixed gas of humidified gas and dry gas is supplied into the soaking zone from at least one gas supply port located in a region of lower ½ of the soaking zone in a height direction so that a dew point measured in a region of upper ⅕ of the soaking zone in the height direction and a dew point measured in a region of lower ⅕ of the soaking zone in the height direction are both −20° C. or more and 0° C. or less.

公开(公告)号：US20160304982A1

公开(公告)日：2016-10-20

申请号：US15103495

申请日：2014-12-11

Applicant: JFE STEEL CORPORATION

Inventor： Yoichi MAKIMIZU ,  Yoshitsugu SUZUKI ,  Mai AOYAMA ,  Hiroshi HASEGAWA ,  Gentaro TAKEDA

IPC: C21D9/46 ,  C23C2/40 ,  C23C8/14 ,  C21D1/26 ,  C22C38/04 ,  C22C38/02 ,  C22C38/00 ,  C23C2/06 ,  C23C8/80

CPC classification number: C21D9/46 ,  C21D1/26 ,  C21D1/74 ,  C21D8/04 ,  C22C18/04 ,  C22C38/00 ,  C22C38/002 ,  C22C38/02 ,  C22C38/04 ,  C22C38/58 ,  C23C2/02 ,  C23C2/06 ,  C23C2/28 ,  C23C2/40 ,  C23C8/14 ,  C23C8/80

Abstract: A method for producing high-strength galvannealed steel sheets having excellent workability and fatigue resistance. The method comprises subjecting a steel sheet to an oxidation treatment, the oxidation treatment including heating the steel sheet in an upstream stage at a temperature in the range of 400° C. to 750° C. in an atmosphere having an O2 concentration of not less than 1000 ppm by volume and a H2O concentration of not less than 1000 ppm by volume and a downstream stage at a temperature in the range of 600° C. to 850° C. in an atmosphere having an O2 concentration of less than 1000 ppm by volume and a H2O concentration of not less than 1000 ppm by volume. The method further comprises subjecting the steel sheet to reducing annealing, hot-dip galvanizing treatment and alloying treatment.

Abstract translation: 一种制造具有优异的加工性和耐疲劳性的高强度合金化热浸镀锌钢板的方法。 该方法包括对钢板进行氧化处理，所述氧化处理包括在O2浓度不低于的气氛中，在400℃至750℃范围内的温度下在上游阶段加热钢板 在氧浓度小于1000ppm的气氛中，在600℃至850℃的温度范围内，在1000体积％以上的H 2 O浓度和不低于1000ppm体积的H 2 O浓度以及下游阶段， 体积和不小于1000ppm体积的H 2 O浓度。 该方法还包括对钢板进行减少退火，热浸镀锌处理和合金化处理。

公开(公告)号：US20160102379A1

公开(公告)日：2016-04-14

申请号：US14891850

申请日：2014-05-19

Applicant: JFE STEEL CORPORATION

Inventor： Yoichi MAKIMIZU ,  Yoshitsugu SUZUKI ,  Yasunobu NAGATAKI

IPC: C21D9/46 ,  C23C2/02 ,  C23C2/28 ,  C23C2/40 ,  C23C2/06 ,  C22C38/58 ,  C22C38/54 ,  C22C38/50 ,  C22C38/48 ,  C22C38/44 ,  C22C38/42 ,  C22C38/34 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/00 ,  C21D6/00 ,  C21D1/26 ,  C21D1/74 ,  C23C2/12

CPC classification number: C21D9/46 ,  C21D1/26 ,  C21D1/74 ,  C21D6/004 ,  C21D6/005 ,  C21D6/008 ,  C22C38/002 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/34 ,  C22C38/42 ,  C22C38/44 ,  C22C38/48 ,  C22C38/50 ,  C22C38/54 ,  C22C38/58 ,  C23C2/02 ,  C23C2/06 ,  C23C2/12 ,  C23C2/28 ,  C23C2/285 ,  C23C2/40

Abstract: There is provided a method for manufacturing a high-strength galvannealed steel sheet having excellent coating adhesiveness and corrosion resistance whose base material is a high-strength steel sheet containing Si and Mn. The method includes performing an oxidation treatment on a steel sheet including Si and Mn in a first zone having an atmosphere of an oxygen concentration, thereafter performing an oxidation treatment in a second zone having an atmosphere of an oxygen concentration, thereafter performing reduction annealing and galvanizing, and further performing an alloying treatment by heating the galvanized steel sheet.

Abstract translation: 提供了一种制造具有优异的涂层粘附性和耐腐蚀性的高强度合金化热浸镀锌钢板的方法，其基材是含有Si和Mn的高强度钢板。 该方法包括在具有氧浓度的第一区域中对包含Si和Mn的钢板进行氧化处理，然后在具有氧浓度的气氛的第二区域进行氧化处理，然后进行还原退火和镀锌 进一步进行通过加热镀锌钢板的合金化处理。