| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a hot-dip galvannealed steel sheet having tensile strength of 780 MPa or more and excellent in a yield-ratio, and a method for manufacturing the same. <P>SOLUTION: The hot-dip galvannealed steel sheet is provided with a hot-dip galvannealed layer on the surface of the steel sheet; has a chemical composition including, by mass%, 0.065-0.12% C, 0.001-0.2% Si, more than 2.0 and 2.7% or less Mn, 0.1% or less P, 0.01% or less S, 0.001-0.25% sol. Al, 0.12-0.30% Ti, 0.01% or less N, and 0.01% or less O; and has a steel structure containing retained austenite of 3.0% or less by an area rate. <P>COPYRIGHT: (C)2012,JPO&INPIT |
