| 摘要 |
Provided are a high-strength galvanized steel sheet with excellent formability and shape fixability having a tensile strength (TS) of 1180 MPa or more, a total elongation (EL) of 14% or more, a hole expansion ratio (») of 30% or more, and a yield ratio (YR) of 70% or less, and a method for manufacturing the high-strength galvanized steel sheet. The high-strength galvanized steel sheet with excellent formability and shape fixability has a chemical composition comprising, by mass%, C: 0.10% or more and 0.35% or less, Si: 0.5% or more and 3.0% or less, Mn: 1.5% or more and 4.0% or less, P: 0.100% or less, S: 0.02% or less, Al: 0.010% or more and 0.5% or less, and the balance being Fe and inevitable impurities and a microstructure including, in terms of area ratio, 0% or more and 5% or less of polygonal ferrite phase, 5% or more of bainitic ferrite phase, 5% or more and 20% or less of martensite phase, 30% or more and 60% or less of tempered martensite phase, and 5% or more and 20% or less of retained austenite phase, in which an average prior-austenite grain diameter is 15 µm or less. |
