中科微点-全球专利检索

  1. Login
  2. Sign Up

Search Results

6 records (took 0.01 seconds)

    METHOD FOR PRODUCING A COATED STEEL SHEET HAVING IMPROVED STRENGHT, DUCTILITY AND FORMABILITY
    3.
    发明申请
    METHOD FOR PRODUCING A COATED STEEL SHEET HAVING IMPROVED STRENGHT, DUCTILITY AND FORMABILITY 有权

    公开(公告)号：US20250122590A1

    公开(公告)日：2025-04-17

    申请号：US18890744

    申请日：2024-09-19

    Applicant: ArcelorMittal

    Inventor： Jean- Philippe MASSE ,  Jean-Christophe HELL

    IPC: C21D9/46 ,  B32B15/01 ,  C21D1/18 ,  C21D1/19 ,  C21D1/26 ,  C22C38/02 ,  C22C38/06 ,  C22C38/34 ,  C22C38/38 ,  C23C2/02 ,  C23C2/06 ,  C23C2/12 ,  C23C2/40 ,  C23F17/00 ,  C25D3/22 ,  C25D3/56

    Abstract: A method is for producing a high strength coated steel sheet having a yield stress YS>550 MPa, a tensile strength TS>980 MPa, and improved formability and ductility. The steel contains: 0.15%≤C≤0.25%, 1.2%≤Si≤1.8%, 2%≤Mn≤2.4%, 0.1%≤Cr≤0.25%, Al≤0.5%, the balance being Fe and unavoidable impurities. The sheet is annealed at a temperature between TA1=Ac3−0.45*(Ms−QT) and TA2=830° C. for at least 30 s then quenched by cooling it to a quenching temperature QT between 180° C. and 300° C., then heated to a partitioning temperature PT between 380° C. and 480° C. and maintained at this temperature for a partitioning time Pt between 10 s and 300 s, then either hot dip coated and cooled to the room temperature with a cooling rate of at least 25° C./s below 300° C., or directly cooled to the room temperature with a cooling rate of at least 25° C./s and further electro-galvanized, or cooled to the room temperature with a cooling rate of at least 25° C./s without coating. The steel contains 5% to 25% of intercritical ferrite, at least 50% of partitioned martensite, at least 10% of residual austenite, less than 10% of fresh martensite, and bainite, the sum of partitioned martensite and bainite being at least 60%. It also relates to the obtained coated or non coated sheet.

    METHOD FOR PRODUCING A TWIP STEEL SHEET HAVING AN AUSTENITIC MICROSTRUCTURE
    4.
    发明申请
    METHOD FOR PRODUCING A TWIP STEEL SHEET HAVING AN AUSTENITIC MICROSTRUCTURE 审中-公开

    公开(公告)号：US20190276910A1

    公开(公告)日：2019-09-12

    申请号：US16302988

    申请日：2017-05-23

    Applicant: ARCELORMITTAL

    Inventor： Jean-Christophe HELL ,  Nicolas CHARBONNIER ,  Thierry IUNG ,  Blandine REMY

    IPC: C21D9/46 ,  C21D8/02 ,  C22C38/02 ,  C22C38/58 ,  C22C38/06 ,  C22C38/42 ,  C22C38/44 ,  C22C38/46

    Abstract: A method for manufacturing a recovered steel sheet having an austenitic matrix presenting at least one mechanical property (M) equal or above a target value Mtarget is provided. The method includes a calibrating process involving heat on at least 2 samples of the steel, corresponding to Pareq values P, submitting said samples to X-ray diffraction so as to obtain spectrums including a main peak whose width at mid height FWHM is being measured, measuring a mechanical property (M) of said samples, measuring a recovery or recrystallization state of each sample, drawing a curve of M as a function of FWMH in a domain where the samples are recovered from 0 to 100%, but not recrystallized. The method further includes calculating a FWHMtarget corresponding to a target mechanical property Mtarget, determining a pareq value Ptarget of the heat treatment to perform to reach Mtarget and selecting a time ttarget and a temperature T°target corresponding to the Ptarget value. The method further includes feeding a recrystallized steel sheet having a Mrecrystallization, cold-rolling the recrystallized steel sheet in order to obtain a steel sheet having a Mcold-roll and annealing the cold rolled steel sheet at a temperature T°target during a time ttarget.

Patent Agency Ranking