| 摘要 |
PROBLEM TO BE SOLVED: To provide a high-tensile hot-dip galvannealed steel sheet having such a hot-dip galvannealed layer with adequate adhesiveness as not to be peeled from a base steel sheet even when the steel sheet has been subjected to a working operation including sliding, and to provide a method for manufacturing the same. SOLUTION: The high-tensile hot-dip galvannealed steel sheet has the hot-dip galvannealed layer formed on the surface of the base steel sheet. The base steel sheet includes 0.04-2.5% Si, and has such surface roughness that an arithmetic mean angle of slope (RΔa) is 23.0°or more and a root-mean-square angle of slope (RΔq) is 29.0°or more at 60% or more of all measured points, when the surface roughness has been measured at a plurality of the points with a laser microscope after the hot-dip galvannealed layer has been dissolved and removed with an acid. COPYRIGHT: (C)2011,JPO&INPIT |
