| 摘要 |
Provided is a high-strength hot-dip galvanized steel sheet which has excellent deep drawability and stretch flangeability and which has a TS of 440 MPa or higher, an average r value of 1.2 or more, and a ? of 80% or higher. Also provided is a process for producing the galvanized steel sheet. The steel contains, in terms of mass%, 0.010-0.06% C, 0.5-1.5%, excluding 0.5%, Si, 1.0-3.0% Mn, 0.005-0.1% P, up to 0.01% S, 0.005-0.5% sol. Al, up to 0.01% N, 0.010-0.090% Nb, and 0.015-0.15% Ti, the contents of Nb and C in the steel satisfying the relationships (Nb/93)/(C/12)<0.20 and 0.005=C*=0.025, and has a ferrite content and a martensite content of 70% or higher and 3% or higher, respectively, in terms of areal proportion. C*=C-(12/93)Nb-(12/48){Ti-(48/14)N} (C, Nb, Ti, and N indicate the contents of C, Nb, Ti, and N, respectively, in the steel). |
