公开(公告)号：US20140170439A1

公开(公告)日：2014-06-19

申请号：US14116734

申请日：2012-05-03

Applicant: ARCELORMITTAL INVESTIGACION Y DESAROLLO SL

Inventor： Sebastien Allain ,  Jan Mahieu ,  Mickael Denis Crouvizier ,  Thierry Mastrorillo ,  Arnaud Hennion

IPC: B32B15/01 ,  C22C38/58 ,  C22C38/42 ,  C22C38/00 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C21D8/02 ,  C22C38/34

CPC classification number: B32B15/013 ,  C21D1/20 ,  C21D8/0247 ,  C21D8/0263 ,  C21D9/46 ,  C21D2211/002 ,  C21D2211/004 ,  C22C38/001 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/34 ,  C22C38/42 ,  C22C38/58 ,  Y10T428/12799

Abstract: The present invention provides a cold rolled steel sheet. The steel sheet has a strength greater than 1000 MPa, a uniform elongation greater than 12% and a V-bendability greater than 90°. The composition of the steel sheet includes, expressed in per cent by weight, 0.15%≦C≦0.25%, 1.8%≦Mn≦3.0%, 1.2%≦Si≦2%, 0%≦Al≦0.10%, 0%≦Cr≦0.50%, 0%≦Cu≦1%, 0%≦Ni≦1%, 0%≦S≦0.005%, 0%≦P≦0.020%, Nb≦0.015%, Ti≦0.020%, V≦0.015%, Co≦1%, N≦0.008%, B≦0.001% whereby Mn+Ni+Cu≦3%. The remainder of the composition consists of iron and inevitable impurities resulting from processing. The microstructure includes, in area percentage, 5 to 20% polygonal ferrite, 10 to 15% residual austenite, 5 to 15% martensite and a balance of bainite. The bainite is in the form of laths and includes carbides between the laths. A number N of inter-lath carbides larger than 0.1 micrometers per unit of surface area is less than or equal to 50000/mm2. A fabrication method and a motor vehicle are also provided.

Abstract translation: 本发明提供一种冷轧钢板。 钢板的强度大于1000MPa，均匀伸长率大于12％，V形弯曲度大于90°。 钢板的组成包括：以重量百分比计，0.15％＆lt; NlE; C＆NlE; 0.25％，1.8％＆nlE; Mn＆amp; NlE; 3.0％，1.2％＆amp; NlE; Si＆NlE; 2％，0％＆amp; ，0％＆nlE; Cr＆nlE; 0.50％，0％和nlE; Cu和nlE; 1％，0％和nlE; Ni和nlE; 1％，0％ ，TiNl; 0.020％，V＆NlE; 0.015％，Co＆NlE; 1％，N＆amp; NlE; 0.008％，B＆NlE; 0.001％，由此Mn + Ni + Cu＆NlE; 3％。 组合物的其余部分由加工产生的铁和不可避免的杂质组成。 微观结构包括面积百分比为5至20％的多边形铁素体，10至15％的残余奥氏体，5至15％的马氏体和贝氏体的平衡。 贝氏体是板条的形式，包括板条之间的碳化物。 每单位表面积大于0.1微米的层间碳化物数量N小于或等于50000 / mm2。 还提供了制造方法和机动车辆。