Hot-dip hot-dip steel sheet for press working with excellent low-temperature toughness and corrosion resistance and its manufacturing method

摘要

C: 0.0005-0.0050%, Si: 0.30% or less, Mn: 0.70-3.00%, P: 0.05% or less, Ti: 0.01-0. 05%, Nb: 0.01 to 0.04%, B: 0.0005 to 0.0030%, S: 0.01% or less, Al: 0.01 to 0.30%, N: 0.0005 Containing 0.010% and the balance Fe and inevitable impurities, Ti content (%) as [Ti], B content (%) as [B], P content (%) as [P], TB * defined by the following A formula is 0.03 to 0.06, and [B] and [P] formed a hot-dip plated layer on the surface of the cold rolled steel sheet satisfying the following B formula, Press with tensile strength of 340MPa or more and less than 540MPa, excellent secondary processing brittleness, low temperature toughness and corrosion resistance of seam welds, and applicable to fuel tanks Melting-plated high-strength steel sheet for engineering. TB * = (0.11- [Ti]) / (ln ([B]? 10000)) ... A [P] ≰10? [B] +0.03 ... B