| 摘要 |
PROBLEM TO BE SOLVED: To provide a high strength cold rolled steel sheet for deep drawing having a tensile strength of 380 to <540 MPa, having press formability applicable for an automobile field, in particular for a fuel tank, and also having excellent second working brittleness resistance and welded joint efficiency, to provide a high strength hot dip plated steel sheet for deep drawing, and to provide a method for producing the same. SOLUTION: The cold rolled steel sheet has a composition comprising, by mass, 0.0005 to 0.040% C, 0.05 to 0.30% Si, 1.2 to 3.0% Mn, 0.005 to 0.05% P, 0.01 to 0.060% Ti, 0.01 to 0.05% Nb, 0.10 to 0.90% Al, 0.0005 to 0.0050% B and 0.0010 to 0.0070% N, and the balance Fe with inevitable impurities, and in which T* expressed by numerical equation (A) is <0.04%. Further, the absolute value of its tensile strength TS(MPa) is controlled to≥1×10<SP>4</SP>times that of the P content(%). COPYRIGHT: (C)2007,JPO&INPIT
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