HIGH-STRENGTH HOT-ROLLED PLATED STEEL SHEET, AND METHOD FOR PRODUCING SAME

• Main Authors: CHAE JAE-YONG, PARK KYONG-SU
• Format: Patent
• Language: Chinese; English
• Published: 07.08.2020
• Subjects: ALLOYS; CHEMISTRY; FERROUS OR NON-FERROUS ALLOYS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUSMETALS OR ALLOYS; MAKING METAL MALLEABLE BY DECARBURISATION, TEMPERING OR OTHERTREATMENTS; METALLURGY; METALLURGY OF IRON; MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; TREATMENT OF ALLOYS OR NON-FERROUS METALS

A high-strength hot-rolled plated steel sheet according to an embodiment of the present invention contains, in wt%, 0.05-0.5% of C, 0.1-3.0% of Mn, no more than 0.5% (excluding 0%) of Si, no more than0.05% (excluding 0%) of P, no more than 0.03% (excluding 0%) of S, no more than 0.01% (excluding 0%) of Nb, 0.0005-0.005% of B, and 0.005-0.2% of Ti, with the remainder comprising Fe and inevitable impurities, wherein the microstructure contains, in vol%, at least 90% of tempered martensite and at most 5% of at least one crystal phase among bainite, ferrite, pearlite, and residual austenite, thetensile strength is at least 650 MPa, the yield strength is at least 550 MPa, and a ratio of said strengths, that is, yield ratio(yield strength/tensile strength), is at least 0.85. 根据本发明的一个实施例的高强度热轧镀覆钢板，以重量％计，所述钢板包含C：0.05～0.5％、Mn：0.1～3.0％、Si：0.5％以下(0％除外)、P：0.05％以下(0％除外)、S：0.03％以下(0％除外)、Nb：0.01％以下(0％除外)、B：0.0005～0.005％、Ti：0.005～0.2％、余量的Fe和不可避免的杂质，以体积分数计，微细组织包含90％以上的回火马氏体、5％以下的贝氏体、铁素体、珠光体或残留奥氏体中的任何一种以上结晶相，拉伸强度为650MPa以上，屈服强度