High-strength hot-rolled steel sheet and method for manufacturing same
    10.
    发明授权
    High-strength hot-rolled steel sheet and method for manufacturing same 有权
    高强度热轧钢板及其制造方法

    公开(公告)号:US08696832B2

    公开(公告)日:2014-04-15

    申请号:US12866513

    申请日:2009-02-04

    IPC分类号: C22C38/14 C22C38/04 C21D8/02

    摘要: A high-strength hot-rolled steel sheet has a tensile strength (TS) of 540 to 780 MPa, only small variations in strength, and excellent uniformity in strength using a general-purpose Ti-containing steel sheet, which is inexpensive. The high-strength hot-rolled steel sheet includes, on a mass percent basis, 0.05%-0.12% C, 0.5% or less Si, 0.8%-1.8% Mn, 0.030% or less P, 0.01% or less S, 0.005%-0.1% Al, 0.01% or less N, 0.030%-0.080% Ti, and the balance being Fe and incidental impurities. The microstructure have a bainitic ferrite fraction of 70% or more, and the amount of Ti present in a precipitate having a size of less than 20 nm is 50% or more of the value of Ti* calculated using formula (1): Ti*=[Ti]−48/14×[N] (1) where [Ti] and [N] represent a Ti content (percent by mass) and a N content (percent by mass), respectively, of the steel sheet.

    摘要翻译: 高强度热轧钢板的拉伸强度(TS)为540〜780MPa,强度变化小,使用廉价的通用含Ti钢板的强度均匀性优异。 高强度热轧钢板以质量%计含有0.05%-0.12%C,0.5%以下Si,0.8%-1.8%Mn,0.030%以下P,0.01%以下S,0.005 %-0.1%Al,0.01%以下N,0.030%-0.080%Ti,余量为Fe和附带杂质。 显微组织具有70%以上的贝氏体铁素体分数,并且存在于尺寸小于20nm的析出物中的Ti的量为使用式(1)计算的Ti *值的50%以上:Ti * = [Ti] -48 / 14×[N](1)其中[Ti]和[N]分别表示钢板的Ti含量(质量%)和N含量(质量%)。