| 摘要 |
<p>A high strength cold rolled steel sheet excellent in the balance of strength and workability, characterized in that it comprises, in mass %, C: 0.10 to 0.25 %, Si: 1.0 to 2.0 %, Mn: 1.5 to 3.0 %, P: 0.01 % or less (exclusive of 0 %), S: 0.005 % or less (exclusive of 0 %), Al: 0.01 to 3. 0 %, and the balance: Fe and inevitable impurities, and it has a structure wherein bainitic ferrite and retained austenite account for 70 area % or more and 5 to 20 area % of the whole structure, respectively, and further has a hardness (HV) of 270 or more and a half width of the X-ray diffraction peak for the (200) plane of E-iron of 0.2200 or less.</p> |
