| 摘要 |
PROBLEM TO BE SOLVED: To provide a high-strength hot-dip galvanized steel sheet which has a high strength of 780 to 1,180 MPa, superior spot weldability, and superior "stability of a material quality" which means that tensile strength, total elongation and yield strength vary little even when a manufacture condition (particularly in a cooling process carried out after a steel sheet has been annealed) changes. SOLUTION: The high-strength hot-dip galvanized steel sheet has a composite structure consisting mainly of ferrite and martensite; and has a steel composition comprising, by mass%, 0.05-0.12% C, 0.05% or less Si, 2.7-3.5% Mn, 0.2-0.5% Cr, 0.2-0.5% Mo, and 0.10% or less Al, 0.03% or less P and 0.03% or less S, which are inhibited elements. COPYRIGHT: (C)2006,JPO&NCIPI |
