The invention belongs to the field of metallurgy and cold-rolled plates and strips, and particularly relates to 690MPa-grade ferrite and martensite dual-phase steel. The 690MPa-grade ferrite and martensite dual-phase steel is characterized by comprising the following components of, by mass, 0.08%-0.12% of C, 0.1%-0.4% of Si, 1.8%-2.2% of Mn, less than or equal to 0.010% of P, less than or equal to0.006% of S, 0.03%-0.06% of Al, one or two or more of Ti, Nb and V and the balance iron and inevitable impurities. The preparation method comprises the following steps that smelting and continuous casting are performed to obtain a steel slab, and the steel slab sequentially undergoes heating and hot rolling to obtain a hot-rolled plate; the hot-rolled plate sequentially undergoes laminar coolingand coiling, and then cooling is performed to obtain a steel coil; the steel coil undergoes cold rolling to obtain chilled strip steel; the chilled strip steel sequentially undergoes annealing treatment and leveling treatment, and then air cooling is performed to obtain the 690MPa-grade ferrite and martensite dual-phase steel. In the case of the dual-phase steel, the tensile strength reaches 690 MPa grade or above, the yield strength reaches 380-500 MPa, the percentage elongation after fracture A80 is 22% or above, and the hole expansion rate is larger than or equal to 74%.

    本发明属于冶金和冷轧板带领域,具体涉及一种690MPa级铁素体马氏体双相钢,其特征在于,按质量百分比计,所述双相钢包含:C 0.08‑0.12%、Si 0.1‑0.4%、Mn 1.8‑2.2%、P≤0.010%、S≤0.006%、Al 0.03‑0.06%,以及Ti、Nb和V中的一种或两种以上,余量为铁和不可避免的杂质;所述制备方法包括:冶炼并连铸得到钢板坯,将所述钢板坯依次进行加热和热轧,得到热轧板;将所述热轧板依次进行层流冷却和卷取,后冷却,得到钢卷;将所述钢卷进行冷轧,得到冷硬带钢;将所述冷硬带钢依次进行退火处理、平整处理,后空冷,得到所述690MPa级铁素体马氏体双相钢。本发明双相钢的抗拉强度达到690MPa级以上,屈服强度达到380‑500MPa,断后延伸率A为22%以上,扩孔率≥74%。


    Access

    Download


    Export, share and cite



    Title :

    690MPa-grade ferrite and martensite dual-phase steel as well as preparation method and application thereof


    Additional title:

    一种690MPa级铁素体马氏体双相钢、其制备方法及其应用


    Contributors:
    QIU MUSHENG (author) / HAN YUN (author) / LIU HUASAI (author) / YANG FENG (author) / XIE CHUNQIAN (author) / JIANG YINGHUA (author) / ZOU YING (author) / LIU LIBIN (author) / TENG HUAXIANG (author) / YU MENG (author)

    Publication date :

    2020-09-11


    Type of media :

    Patent


    Type of material :

    Electronic Resource


    Language :

    Chinese


    Classification :

    IPC:    C22C Legierungen , ALLOYS / B60N SEATS SPECIALLY ADAPTED FOR VEHICLES , Sitze besonders für Fahrzeuge ausgebildet / C21D Veränderung der physikalischen Struktur von Eisenmetallen , MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS